Patent Publication Number: US-7901335-B2

Title: Multi-station exercise machine

Description:
RELATED APPLICATION 
     The present application is a Continuation-In-Part of co-pending U.S. patent application Ser. No. 10/633,805 filed on Aug. 4, 2003, and is also a Continuation-In-Part of co-pending U.S. patent application Ser. No. 11/846,472 filed on Aug. 28, 2007, and is also a Continuation-In-Part of co-pending U.S. patent application Ser. No. 11/848,012 filed on Aug. 30, 2007, and the contents of each of the aforementioned co-pending applications are incorporated herein by reference in their entirety, 
    
    
     BACKGROUND 
     1. Field of the Invention 
     This invention relates generally to exercise machines, and is particularly concerned with a multi-station exercise machine in which at least one station has a pivoting user support. 
     2. Related Art 
     There are several different types of exercise for exercising back muscles, including mid-row exercises. There are two basic types of exercise movements, isolation and compound. Isolation movements are designed to isolate a specific muscle or muscle group and to reduce body part movement to involve rotation of a single joint. Leg extensions and biceps curls are examples of isolation movements. Compound movement exercises involve more than one body part and require multiple joint action. Because of this, they exercise a greater number of muscles/muscle groups. There is also a difference in the travel path for the two types of movement. Isolation movements tend to be rotational with concentric travel paths, while compound movements tend to be curvilinear, with elliptical travel paths. 
     Compound movements are a natural and fundamental form of exercise and show up in everything from professional athletics to everyday activities. Jumping, rowing, swimming, and throwing all involve multi-joint movements. Squats, bench presses, chin-ups, bar dips, shoulder presses, and the like, are all compound movement exercises. While fundamental in everyday life, they can be difficult for many people to perform as exercises, requiring balance and coordination as well as strength to follow the proper movement path. Improper form by the exerciser can make the exercise more difficult, increase stress on the joints, and even lead to possible injury. 
     Various exercise machines have been developed for performing compound movement exercises involving different muscles and muscle groups. Some of these have a stationary user support, while others have a pivoting or movable user support, which may or may not be linked to the exercise arm or user engagement means. One problem in most or all prior art designs is the unnatural and exaggerated arcing movement found in pivoting arm exercise machines, which do not accurately simulate the natural body movement found in free weight and/or free bar exercises. 
     Movable user supports linked to the movement of an exercise arm are fairly common in single station exercise machines. U.S. Pat. No. 2,252,156 of Bell and U.S. Pat. No. 6,251,047 of Steams show bicycle and exercise bike designs in which a seat or user support is linked to an exercise arm or crank and pedal system to provide up and down movement to the seat. The most common application of movable user supports is found in rowing and horse riding type exercise machines, which use the weight of the user as the exercise resistance. In U.S. Pat. No. 3,446,503 of Lawton, U.S. Pat. No. 4,743,010 of Geraci, and U.S. Pat. No. 5,342,269 of Huang, a seat and exercise arm are pivotally mounted on the base frame, with the seat linked to the exercise arm for dependent movement. U.S. Pat. No. 4,300,760 of Bobroff, U.S. Pat. No. 5,299,997 of Chen, U.S. Pat. No. 5,356,357 of Wang, U.S. Pat. No. 5,453,066 of Richter, U.S. Pat. No. 5,458,553 of Wu, U.S. Pat. No. 5,503,608 of Chang and U.S. Pat. No. 5,507,710 of Chen all show horse riding type exercise machines. They all consist of a user support pivotally attached to a base frame, and one or more exercise arms pivotally connected to the frame and pivotally linked to the user support. 
     U.S. Pat. No. 6,264,588 of Ellis shows a composite motion movement machine that has a moving exercise arm linked to a movable user support, and a pivoting truck system which is slideably connected to rails mounted both on the main frame and user support. The movable user support and exercise arm are both pivoted at the same point on the base frame, in front of the user support. A belt connects the exercise arm to the truck. When the exercise arm is pushed or pulled, the belt pulls the truck along the rails, forcing the user support to rotate about its pivotal connection to the frame. This design puts all of the user&#39;s weight on one side of the pivot, producing a high initial lifting resistance when the user starts the exercise, and also has no means for properly aligning the exercise arm and user support during the exercise movement. 
     Movable seats linked to exercise arms have also been used in multi-purpose exercise machines, such as U.S. Pat. No. 5,330,405 of Habing, U.S. Pat. No. 5,334,120 of Rasmussen, U.S. Pat. No. 5,669,865 of Gordon, U.S. Pat. No. 5,733,232 of Hsu, and U.S. Pat. No. 6,244,995 of Prsala. In U.S. Pat. No. 5,330,405 of Habing, a lever arm is pivotally connected to the base frame and supports a movable sub-frame including a user support which is also pivotally connected to the stationary base frame. An exercise arm is pivotally mounted on the sub-frame and linked to the lever arm via cables and pulleys, so that movement of the exercise arm pulls the cables lifting the lever arm, and causing the sub-frame to pivot about its connection to the base frame and rise against the weight of the user. U.S. Pat. No. 5,733,232 of Hsu shows another multi-purpose exercise machine with a pivoting seat, but in this case the back pad is stationary and only the seat pad is pivoted. Thus, the seat travels in an arcuate path without any secondary stabilization for the user, forcing the user to try to maintain their balance on the seat as it arcs upward. Also, in this design, the pivot point for the seat is located at a spacing behind the user position, so that all of the user&#39;s weight will oppose the user when starting an exercise from rest. Neither of these machines has any capability for aligning the user and user support with a rigid exercise arm, and thus do not maintain or support the user in the proper position throughout the exercise. 
     Gordon shows a multi-purpose exercise machine that has a hinged, two-piece user support that folds and unfolds with each exercise repetition. The user support consists of a seat portion and a backrest portion, which are pivotally connected together. The user support is pivotally connected to a main frame, as is a first exercise arm. This first exercise arm provides pressing and pulldown exercises. A second exercise arm is pivotally connected to the user support for providing leg exercises. This second arm travels with the seat portion of the user support. A connecting link pivotally connects the first exercise arm with the user support so that movement in the arm forces movement in the user support. The link connects to the user support at the same pivot that joins the seat portion with the backrest portion. In a second embodiment a flexible line connects the user support with the main frame and has user-engaging handles attached to one end so that movement to the handles results in movement to the user support. In this design, the flexible line acts as both connecting link and exercise arm. In both designs, the seat and backrest do not travel in a fixed relationship to each other and additional support such a footrest, safety belts and thigh gripping surfaces are required to keep the user properly and safely positioned in the user support. Because most of the combined weight of the user and user support remain on one side of the user support&#39;s gravitational centerline, this weight is used as partial exercise resistance. Movement of the user support is designed to be an exercise of its own, rather than providing proper positioning/alignment of the user relative to the exercise arm. The folding and unfolding of the two-piece user support constantly works the abdominal and low back muscles, which means that these muscles are being worked even when other exercises are being performed. The user cannot truly isolate any one specific muscle or muscle group. The stomach cannot be worked without working the low back, the arms, chest, shoulders, upper back and legs all must be worked with one another or at the least with both the stomach and low back. Because of this the user cannot fully fatigue other muscles as the abdominals and low back would fatigue first. 
     A squat exercise apparatus is described in both U.S. Pat. No. 5,108,095 of Nichols and U.S. Pat. No. 5,603,678 of Wilson. In Nichols, a four bar linkage system is used to keep the user support (back pad and shoulder pads) vertical while it is being moved along an arcuate exercise path. This design requires a belt around the user&#39;s waist to keep them in the proper position, and is awkward to use. The entire weight of the moving carriage is positioned on one side of the pivotal connection to the main frame, creating an initial starting weight or resistance which may be too heavy for most users, and requires addition of a counter balance to offset the carriage weight. This in turn poses a hazard to anyone standing next to, or walking past, the moving part. Wilson has a generally T-shaped user support frame rotatably mounted on the base of the stationary frame. A back pad, handgrips, and resistance receiving means are all attached to the pivoting user support frame. The user pushes against a fixed foot plate in order to pivot the backrest. There is no secondary user support to properly position the user, and improper positioning could result in serious injury. 
     Various exercise machines are also known which allow users to perform chin up and/or bar dip exercises. Some examples of these machines are described in U.S. Pat. No. 3,592,465 of Fulkerson, U.S. Pat. No. 3,707,285 of Martin, U.S. Pat. No. 4,111,414 of Roberts, U.S. Pat. No. 5,011,139 of Towley, U.S. Pat. No. 5,322,489 of Webb, U.S. Pat. No. 5,449,959 of Holmes, and U.S. Pat. No. 5,540,639 of Potts. In these machines, the user sits or stands on a movable user support, and pushes or pulls with their hands in order to raise their body, assisted by the counter-balanced user support. While the user support moves in these designs, it is not urged to do so by movement of an exercise arm. The only user engaging means or handles are stationary and fixed to the main frame. A further disadvantage of these machines is the limitation of the handle or user gripping position, which may put the hand and/or wrist of the user in an uncomfortable position at some point in the movement, causing undue strain which may lead to injury. U.S. Pat. No. 248,121 of Tuttle and U.S. Pat. No. 5,876,095 of Johnston describe exercise machines for performing dips in which a movable user support or platform is linked to an exercise arm, so that movement of the exercise arm forces movement of the user support. Both of these designs have the user support traveling upward in a generally vertical direction while the user support remains horizontal, and both place the exerciser&#39;s wrist in an awkward starting position. Neither of these designs describes or suggests orienting or aligning the position of the user support to the position of the exercise arm or user engaging means. 
     Current exercise machines for performing compound or multi-joint exercises, whether using composite motion or a fixed user support, do not accurately maintain proper positioning of the user throughout the exercise motion, can result in awkward hand or wrist positions, and often involve exaggerated and unnatural arcing movements, or linear, non-arcing arm movements, rather than the smaller elliptical movement associated with free weight or natural exercise movements. There is no provision for proper positioning of the user relative to the position of the user engaging portion of the exercise arm throughout the entire exercise motion. Often, an awkward starting or finishing position is required, causing strain and potential injury. 
     SUMMARY 
     Embodiments described herein provide for a multi-station exercise machine with a pivoting user support at one or more of the exercise stations. 
     A multi-station exercise machine in one embodiment comprises at least two exercise stations for performing different exercises, at least a first one of the stations having a main frame, a user support frame pivotally associated with the main frame, a user engagement device movably mounted on one of the frames for actuating by a user in order to perform an exercise, and a connecting linkage which translates movement of the user engagement device to movement of the user support. A load provides resistance to movement of the user support frame, user engagement device and/or connecting linkage. The connecting linkage, user support pivot, and user engagement device mount are arranged so that movement of the user engagement device results in self-aligning movement of the user support. 
     The user support frame of the first station in an exemplary embodiment has both a primary user support, such as a seat pad or back pad, and one or more secondary user supports. One secondary user support may be a back pad, shoulder pad, thigh hold-down pads, chest pad, or the like. Another secondary or additional user support may be a foot rest, which may be mounted on, and travel with, the user support frame. Alternatively, a foot rest may be mounted on the main frame. In either case, the foot rest provides additional stabilization to the user, helping them to maintain a proper exercise position and providing additional comfort and support. The use of multiple support pads on the user support frame helps to position the exerciser properly and safely. These supports are in fixed alignment to each other and travel together, keeping the user in the same braced position throughout the entire exercise range of motion. This allows the user to focus on the exercise rather than worrying about their positioning on a moving platform or seat. 
     The exercise arm or user engagement device is movably mounted on the main frame, the user support frame, or the connecting linkage. The connecting linkage translates movement of the exercise arm to movement of the user support, and is movably engaged with at least two of the main frame, exercise arm, and user support. In one embodiment, the user engagement device is movably mounted on the main frame and associated with the connecting linkage. The user support and exercise arm may both be movably mounted on the main frame, with the connecting linkage connected between them. The exercise arm may be mounted for linear movement or may be pivotally mounted for rotational movement. 
     The user support frame may be pivotally mounted on the base of the main frame so that it is relatively low to the ground and readily accessible to the user in entering and exiting the machine, via a single pivot or a multiple pivot assembly. In one embodiment, the user engagement device is also movably mounted on the base of the main frame. In other embodiments, the user engagement device is movably mounted relative to an upright portion of the main frame. The user engagement device may comprise completely rigid or partially rigid exercise arms with handles for gripping by the user which are movable between a start position and an end position. The user&#39;s hands may be at a different elevation in the end position than in the start position. 
     A pivot assembly which pivotally supports the user support frame may be located beneath the user support frame. The connecting linkage may be rigid, flexible, or partially flexible, and may be adjustable in length or position. The user engagement device or exercise arm may have one or two handles. If handles are provided, they may be rigid or flexible, fixed or self-aligning, and may provide two dimensional or three dimensional movement. 
     Where the user engagement device comprises two exercise arms, the exercise arms may be movable independently or in unison. In one embodiment, the user engagement device and connecting linkage are both movably associated with the main frame. The user engagement device may be a bi-directional exercise arm. 
     The pivot mounting of the user support defines a vertical gravitational center line of the pivotal movement, and in one embodiment portions of the combined weight of the user and user support frame are positioned on both sides of the vertical gravitational center line in at least one of the start and end positions of the exercise. In one embodiment, a portion of the combined weight of the user and user support is positioned on the movement side (i.e. the side the user support is pivoting towards) of the gravitational center line in the start position. This reduces the initial lifting resistance. By finishing the exercise with a portion of the combined user and user support weight on the trailing side of the center line in the movement direction, resistance “drop-off” at the end of an exercise is reduced. This distribution reduces the effect of the user&#39;s body weight on the resistance felt during the exercise. This is the opposite of most exercise devices that have moving user supports, which tend to rely on the weight of the user for resistance. Whether it is the starting or the finishing position, most prior art pivoting user supports place the majority of the user&#39;s weight on one or the other side of the gravitational center line of the pivoting movement, resulting in either a high initial lifting resistance, or else a resistance “drop off” at the end of the exercise. 
     The exercise resistance or load may comprise a weight stack, weight plates mounted on pegs, or other types of resistance such as hydraulic, pneumatic, electromagnetic, or elastic bands, and may be associated with any of the moving parts, i.e. the user support frame, exercise arm, or connecting linkage. Where the exercise resistance is a weight stack, multiple exercise stations may share the same weight stack or load for exercise resistance, or separate weight stacks may be provided for each station. 
     The multi-station exercise machine may have one or more exercise stations with pivoting user supports as described above, and the exercise stations with moving user supports may be designed for performing various types of exercises, including both compound and isolation exercises. In one embodiment, the exercise stations are adapted for performing different exercises. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The details of the present invention, both as to its structure and operation, may be gleaned in part by study of the accompanying drawings, in which like reference numerals refer to like parts, and in which: 
         FIG. 1  is a side elevation view of a multi-station exercise machine according to one embodiment, with a user seated on each station in a start position adopted at the beginning of an exercise movement; 
         FIG. 2  is a side elevation view similar to  FIG. 1 , illustrating each station in an exercise end position; 
         FIG. 3A  is a top plan view of the pec fly exercise station of the machine of  FIGS. 1 and 2 , illustrating the start position of the exercise arms as in  FIG. 1 ; 
         FIG. 3B  is a top plan view similar to  FIG. 3A , illustrating the end position of the exercise arms as in  FIG. 2 ; 
         FIG. 4  is a top plan view of the rear deltoid exercise station of the machine of  FIGS. 1 and 2 , illustrating the exercise arm movement; 
         FIG. 5  is a side elevation view of a multi-station exercise machine according to another embodiment, with a user seated on each exercise station of the machine in the start position adopted at the beginning of the exercise; 
         FIG. 6  is a side elevation view of the exercise machine of  FIG. 5  with each exercise station in the end position of the exercise; 
         FIG. 7  is a side elevation view of a two station exercise machine according to another embodiment, with a user seated on each station of the machine in the start position adopted at the beginning of the exercise; 
         FIG. 8  is a side elevation view of the exercise machine of  FIG. 7  with each station of the machine in the end position of the associated exercise; 
         FIG. 9  is a top plan view of another embodiment of a multi-station exercise machine which has three exercise stations; 
         FIG. 10  is a side elevation view of the shoulder press exercise station of the machine of  FIG. 9  with a user seated on the user support in the start position of a shoulder press exercise; 
         FIG. 11  is a side elevation view of the shoulder press exercise station similar to  FIG. 10  but with the user and station in the end position of a shoulder press exercise; 
         FIG. 12  is a side elevation view of the chin up or pull down exercise station of the machine of  FIG. 9  with a user seated on the user support in the start position of a chin up exercise; 
         FIG. 13  is a side elevation view of the chin up exercise station similar to  FIG. 12  but with the user and station in the end position of a chin up exercise; 
         FIG. 14  is a side elevation view of the leg press exercise station of the machine of  FIG. 9  with a user seated on the user support in the start position of a leg press exercise; 
         FIG. 15  is a side elevation view of the leg press exercise station similar to  FIG. 14  but with the user and station in the end position of a leg press exercise; 
         FIG. 16  is a top plan view of another embodiment of a multi-station exercise machine; 
         FIG. 17  is a side elevation view of the leg extension station of the machine of  FIG. 16  in a start position for a leg extension exercise; 
         FIG. 18  is a side elevation view similar to  FIG. 17  but with the leg extension station in a finish position for a leg extension exercise; 
         FIG. 19  is a side elevation view similar to  FIG. 17  but illustrating a user in position on the leg extension station in the start position; 
         FIG. 20  is a side elevation view similar to  FIG. 19  but illustrating the end of a leg extension exercise; 
         FIG. 21  is a side elevation view of the arm exercise station of the machine of  FIG. 16  in a start position for an arm exercise; 
         FIG. 22  is a side elevation view of the arm exercise station similar to  FIG. 21  but illustrating an end position for an arm exercise; 
         FIG. 23  is a side elevation view of the arm exercise station similar to  FIG. 21  but with a user positioned on the arm exercise station in the start position for an arm exercise; and 
         FIG. 24  is a side elevation view similar to  FIG. 23  with the user in position, but illustrating the end position of the exercise. 
     
    
    
     DETAILED DESCRIPTION 
     Certain embodiments as disclosed herein provide for a multi-station exercise machine having multiple exercise stations, at least one of which has an exercise arm or user engagement device and pivoting user support which travel in a dependent relationship. 
     After reading this description it will become apparent to one skilled in the art how to implement the invention in various alternative embodiments and alternative applications. However, although various embodiments of the present invention will be described herein, it is understood that these embodiments are presented by way of example only, and not limitation. 
       FIGS. 1 to 4  illustrate a multi-station exercise machine  10  according to one embodiment, which has a first exercise station  12  for performing pectoral (“pec”) fly exercises and a second exercise station  14  for performing rear deltoid exercises. The two stations  12 ,  14  share a common load or weight stack and are mounted face-to-face on different portions of a main frame assembly with the shared weight stack between them. In this embodiment, the main frame assembly comprises main frame portions of the two exercise stations and a housing  15  for the shared weight stack secured between the main frame portions.  FIG. 1  illustrates both stations of the machine in a start position while  FIG. 2  illustrates both stations in the finish position, with  FIGS. 3 and 4  illustrating the exercise arm movements of each machine, as described in more detail below.  FIGS. 1 and 2  illustrate a first user or exerciser  16  seated on the pec fly station in the start and end positions of the pec fly exercise, and a second user or exerciser  18  seated on the rear deltoid station in the start and end positions of the rear deltoid exercise. 
     Both stations  12 ,  14  have a pivoting user support and movement of the user engagement device is translated into rocking movement of the user support by a connecting linkage. The pectoral fly (“pec fly”) exercise machine  12  is designed for performing pec fly exercises similar to the free weight pectoral fly exercise, but without the disadvantages of a free weight exercise. The pectoral fly machine of this embodiment is designed to combine three pectoral fly exercises in one machine, specifically a straight pec fly, a decline pec fly, and an incline pec fly, as described in more detail below.  FIGS. 1 and 3A  illustrate the start position of the pec fly station, while  FIGS. 2 and 3B  illustrate the end position. 
     The pec fly station  12  has a main frame portion comprising a base section  20 , a rear upright  22 , and a pivot mounting post  24  on the base section. A generally L shaped user support  25  is pivotally mounted on the pivot mounting post  24  for rotation about pivot axis  26 . The user support  25  has a base  28  on which a seat pad  30  is mounted, and an upright  32  on which back pad  34  is mounted, with the base and seat pad comprising a primary user support and the upright and back pad comprising a secondary user support. A foot rest or foot plate  35  is mounted at the forward end of the base  28  and comprises an additional user support. The exercise resistance comprises a selectorized weight stack in housing  15  and is linked to the base of the user support via a cable and pulley linkage  36 , only part of which is visible in the drawings. The cable and pulley linkage  36  includes a pulley  38  at the forward end of the base  28  adjacent the foot plate, and a cable  40  extending from an anchor on the base of the main frame, around pulley  38 , around a second pulley  42  on the frame base, and then into the weight stack housing to extend around additional guide pulleys before linking to the weight stack in a conventional manner. 
     A pair of multi-part, articulating exercise arms  44  are rotatably mounted via pivot shafts  45  at their first ends on the base section of the main frame, one on each side of the user support, as best illustrated in  FIGS. 3A and 3B . Each exercise arm  44  has a first elongate part  46  having a first end pivoted on pivot shaft  45  and a second end, and an elongated handle arm  48  which has a first end rotatably mounted on the second end of part  46  for rotation about pivot axis  50 . A user-engaging grip  52  is rotatably mounted on the second end of handle arm  48  for rotation about pivot axis  54 . The pivotal connection between each handle arm and the respective elongate part  46  of the exercise arm allows the handles to rotate inwardly and outwardly about pivot axes  50 , as indicated by arrows  55  in  FIGS. 3A and 3B , so that the combined movement of the elongate exercise arm and elongated handle about pivots  45  and  50  results in forward and rearward elliptical travel paths (see arrow  56 ). At the same time, the upwardly extending hand grips  52  rotate about their own axes  54  during an exercise movement, as indicated by arrows  58  in  FIGS. 3A and 3B . 
     A resistance cam  60  is mounted on each pivot shaft  45 . A cable or flexible link  62  has a first end attached to a cam  60  of a first exercise arm, and extends over a first series of pulleys  64 ,  65 ,  66  mounted on the rear upright of the main frame. Cable  62  then extends around a swivel pulley  68  pivotally mounted at the upper end of the rear upright  32  of the user support frame, and then around a second series of pulleys  66 ,  65 ,  64  on the opposite side of the rear upright, before attaching to the cam  60  of the second exercise arm. This cable and pulley assembly provides a connecting link between the user support and exercise arm, and translates forward rotational movement of one or both exercise arms into rearward rotational movement of the user support. 
       FIG. 1  illustrates a user  16  seated on the user support of the pec fly station  12  in the exercise start position, while  FIG. 3A  is a plan view of the pec fly station in the same position but without the user. The user sits on the seat in a slightly forwardly inclined position, and places their feet on foot pad  35 , which rests on a support post  70  on the base of the frame in the start position. They grab the hand grips  52  and push the hand grips and associated exercise arm forwards into the end position of  FIGS. 2 and 3B . In the start position, the user&#39;s upper body is inclined forwardly at an orientation of around 3 degrees to a vertical gravitational centerline  72  passing through the user support pivot axis  26 . The user&#39;s elbows are bent with the arms out to the side and the hands slightly below the shoulders, mimicking the start position of the arms for a free weight pec fly exercise, while the body is forwardly inclined, in position for an incline pectoral fly. Pushing the exercise arms forward causes the cams  60  mounted on the exercise arm pivot shafts to rotate, which pulls both ends of the cable  62  which is reeved around the swivel pulley  68  mounted at the upper end of the user support. This causes the user support  25  to pivot rearward about pivot  26  against the exercise resistance linked to the forward end of the user support. This action moves the user from a forwardly inclined position to a slightly reclined position as illustrated in  FIG. 2 , ending with their arms extending forward in front of their body, similar to the ending position of the arms for a free weight pec fly exercise, while the body is in a decline pec fly position. 
       FIGS. 3A and 3B  illustrate the movement of the three parts of each articulating exercise arm  44 , comprising the first exercise arm portions or parts  46 , elongated handle arms  48 , and user-engaging grips  52 , from the start to the end position of the exercise. The three pivot axes  45 ,  50 , and  54  imitate the joint movement of the shoulder, elbow, and wrist, respectively, when performing a free weight pectoral dumbbell fly exercise. 
     The user support pivot  26  is positioned directly under the user in this exercise station, and the gravitational centerline  72  of the user support pivotal movement runs very close to the centerline of the user&#39;s hip, allowing a balanced portion of the user support and user to be positioned on each side of the line  72  in both the start and end position. Because the user support seat rises upward as it rotates while the exercise arms remain in the same horizontal plane, the positioning of the user&#39;s hands, relative to their shoulders, is slightly higher in the start position than the end position. This, coupled with the fact that the user is in all three pectoral fly positions (decline, flat/straight, and incline) during the exercise, allows this exercise machine to combine all three possible pectoral fly exercises in one exercise movement for greater muscle involvement. In the start position, the user is in an incline pectoral fly position, and travels through a flat or straight pec fly position during the exercise, finishing the exercise in a decline pectoral fly position. This produces an enhanced workout which saves time and money, because three machines or exercise stations providing three pec fly exercises are combined into one. 
       FIG. 1  also illustrates the rear deltoid or upper back exercise station  14  of the multi-station machine in a start position while  FIG. 2  illustrates the station  14  in an end position for the exercise, and  FIG. 4  illustrates movement of the user&#39;s arms in performing a rear deltoid exercise on station  14 . 
     The station  14  has a main frame portion  85  comprising a base section  102  and upright section  104 , a user support frame  88  pivotally mounted on the base section  102 , a user engagement device comprising user engaging handles  90  attached to opposite ends of a cable or flexible exercise arm member  92  extending around a series of pulleys  134 ,  135 ,  136 , an exercise resistance comprising the weight stack in housing  15  linked to the user support frame via a cable and pulley assembly  95 , and a multiple cam connecting linkage extending from the user engagement device to the user support frame. In this embodiment, the multiple cam linkage comprises a dual cam assembly  96 ,  98  and first and second cables or flexible links  99 ,  100  extending between cable  92  and a forward end of the user support frame, as explained in more detail below. The flexible links  99 ,  100  may comprise any suitable flexible elongate members such as cables, belts, lines, chains and the like. 
     The main frame portion  85  also has user support pivot mount plates  105  extending upwardly at the rear end of the base section  102 , and a pair of cam pivot mounting plates  106  extending upwardly from the base section between the upright section  104  and the weight stack housing  15 . 
     The user support frame  88  is generally T-shaped, with a base  108  pivotally mounted between the upper ends of the pivot mount plates via pivot pin  110 , and an upright post  112  extending upwards from base  108  and curving rearward at its upper end. A user support seat pad  114  is mounted on the rear part of the base, while a chest support pad  115  is mounted at the end of post  112 . A foot support or footplate  116  is secured to the forward end of the base  108 . The rear part of the base  108  is linked to the weight stack via the second cable and pulley assembly  95 . As best illustrated in  FIG. 2 , cable and pulley assembly  95  comprises a set of pulleys mounted between mounting plates  118  on the undersurface of base  108 , a set of pulleys (not visible in the drawings) mounted between the pivot mounting plates  105 , and a cable  120  extending from an anchor back and forth over the two sets of pulleys, and then running through the base section  102  of the main frame into the weight stack housing where it extends over further pulleys (not visible in the drawings) before linking in any conventional manner with the weight stack. 
     The forward end of the user support frame is linked to the user engaging handles via the connecting linkage  100 ,  98 ,  96 , and  99 , and the cable  92 , as explained in more detail below. The connecting linkage includes the first and second cam portions  96 ,  98  of different diameter or profile mounted for rotation about a common pivot axis  122  via a common pivot shaft rotatably mounted between the upper ends of cam plates  106 . The forward end of the user support base  108  is linked to the first, smaller cam  98  by cable  100  which extends from the cam around a pulley  124  at the lower end of upright  104 , around a second pulley  125  on the frame base beneath the user support base, and which is tied off at anchor  126  on the underside of the base  108  close to the footplate  116 . 
     A second cable  99  extends from the second, larger cam  96  around a fixed pulley  128  at the forward end of base  102  and is anchored to the housing of a floating pulley  130 . As noted above, the user engagement device in this embodiment comprises the handles  90  and flexible cable  92  which has opposite ends secured to the respective handles  90 . Cable  92  extends from one handle between pulleys  132  of one swivel pulley assembly  134  mounted on upright  104 , around one of a pair of fixed, side-by-side pulleys  135  on the upright above the swivel pulley assemblies  134 , then around one of a pair of parallel pulleys  136  on opposite sides of an upper, generally horizontal portion of the upright  104 , and then downwardly around the floating pulley  130 . From the pulley  130 , cable  92  extends back up around the second one of the pulleys  136 , around the second one of the pulleys  135 , and is then reeved between the two pulleys  138  in the second swivel pulley assembly  140  (see  FIG. 4 ), before connecting to the second handle  90 . With this arrangement, rearward movement of one or both handles pulls up the floating pulley  130 , rotating the cams  96  and  98 . Cables  99  and  100  are oppositely connected to the respective cam portions  96  and  98  so that pulling on handles  90  unwinds cable  99  from cam portion  96  while winding cable  100  onto cam portion  98 , rotating the user support frame upwardly about pivot  110 . 
     The swivel mounts  142  of the two swivel pulley assemblies  134 ,  140  (only one of which is visible in the drawings) allow the assemblies to pivot in and out as indicated in  FIG. 4  as the user moves their hands in an exercise movement which exercises the upper back muscles. In order to perform a rear deltoid exercise, the user  18  first sits on the user support in the position of  FIG. 1  and the solid line position of  FIG. 4 , placing their feet on the footplate  116 , their chest against the chest pad  115 , and grabs the handles  90  with their arms straight in front of their body, slightly bent, and their hands close together, as indicated in  FIG. 1  and in solid lines in  FIG. 4 . At the start of the exercise, the user is in a slightly reclined orientation at an angle of around 6 degrees to the gravitational centerline or vertical centerline  144  which extends through the user support pivot  110 , as indicated in  FIG. 1 . 
     From the position illustrated in  FIG. 1 , the user pulls the handles or hand grips  90  rearward and outward. Since the exercise arm in this embodiment is a flexible cable  92  which extends from each handle between the pulleys of a respective set of swivel pulley assemblies  134 ,  140  which can swivel inward and outward, the user controls the exercise path and thus the type of upper back exercise performed. In  FIGS. 1 ,  2  and  4 , the user is shown performing a rear deltoid exercise in which the user moves their hands rearward and outward into an end position in which the user&#39;s arms are bent with their hands positioned out to the sides of their body, as illustrated in the dotted line handle position  90 A of  FIG. 4 . As noted above, this movement also pulls the user support upwardly against the exercise resistance, with the chest pad and user upper body ending up in a forward lean of around 20 degrees from the vertical. The user&#39;s arms finish in a bent position with their hands positioned out to the sides, slightly below and forward of their shoulders. 
     The user is in three different positions throughout the exercise, starting in a recline or decline position, traveling through a straight, upright position, and ending in a forward incline position. At the same time, there is a change in elevation of the user&#39;s shoulders between the start and finish position, which amounts to about a four inch change. Additionally, the user can determine the travel path of the user engaging handles or grips  90 . These factors together provide an enhanced workout by involving a greater number of muscles than a rear deltoid exercise performed in only one position, thereby combining multiple exercises into one. 
     Instead of performing a rear deltoid exercise, a user may chose to perform a mid-row type of exercise, pulling their hands back and only slightly outwards. The user may define the travel path of the grips as desired throughout the exercise and may end the exercise with the handles in the position of  FIG. 4  or any other desired position so as to perform different upper back exercises. 
     The gravitational centerline or vertical centerline  144  of the user support pivot axis  110  runs through the exerciser&#39;s thigh, just behind the knee in the start position and ending at mid thigh in the finish position of the rear deltoid exercise illustrated in  FIG. 2 . There is a balanced distribution of weight on each side of the centerline  144  both at the start and end position, minimizing the effect that the weight of the exerciser and user support has on the exercise resistance. The amount of weight positioned on each side of centerline  144  varies only slightly from the start to the finish position. The combined weight of the user and user support has little effect on the amount of starting resistance because a substantially equal amount of weight is balanced rearward of the user support pivot. By the same token, because only a small portion of the user passes through the gravitational centerline during the exercise, there is no appreciable drop-off in resistance felt by the user. 
     The user engagement device of the rear deltoid exercise station of  FIGS. 1 to 4  comprises handles attached to a flexible line or cable  92 , to provide a unilateral, three dimensional user defined exercise motion. The machine is designed to mimic the natural elliptical movement of the corresponding free weight dumbbell exercise, but is able to combine the effectiveness of multiple exercises by rotating the user from reclined to flat to inclined positions throughout the exercise. The connecting linkage  99 ,  96 ,  98 ,  100  which translates movement of the user engagement device into movement of the user support frame is partially flexible and includes at least two axially spaced cams or cam portions rotatably mounted about the same cam axis  122 , arranged so that one cable or flexible link wraps around one of the cam portions while the other unwraps. Pulling on the handles or grips  90  in this station rotates the dual cam assembly in a first direction (clockwise as viewed in  FIGS. 1 and 2 ), unwinding cable  99  from the larger cam  96 , while winding a smaller amount of cable  100  onto the smaller cam  98 . Cams or separate cam portions of different relative diameters can be selected in order to change the ratio between handle movement and user support frame movement, depending on the desired end position for the user support frame. 
     The multi-station exercise machine  10  of  FIGS. 1 to 4  has two stations  12  and  14  which share a common load or weight stack with a cable running from each user support and linking with the weight stack in a manner known in the art. This arrangement allows only one person to exercise on the machine  10  at a time. Alternatively, each station may be associated with its own weight stack or load, with the weight stack housings secured together between the two exercise stations in place of the single weight stack housing  15 . This would allow exercisers to use both stations simultaneously. 
     Both exercise stations  12 ,  14  have a pivoting user support and a user engagement device with a flexible connecting linkage which translated movement of the user engagement device into pivoting movement of the user support. Additionally, in both exercise stations, a vertical gravitational center line of the user support pivotal movement extends through the user and user support in the exercise start and end position, with only a small amount of the weight of the user and user support passing through the center line in an exercise, reducing the effect of the weight of the user and user support on the exercise starting resistance, and also reducing resistance drop-off at the end of an exercise. 
     In both exercise stations, the exercise arms or user engagement devices travel in the opposite direction to the user support, and the user support pivots about a pivot axis on a pivot mount located on the base of the main frame, at a base portion of the user support. The pec fly station has a single connecting link (cable  62 ) which translates movement of the exercise arms into movement of the user support, while the rear deltoid station has a multiple part connecting linkage of cables and cams. The user support rocks rearward between the exercise start and end positions in the pec fly station, while the user support rocks forward in the rear deltoid station. The user engaging grips or handles travel away from the user in the pec fly station, but travel towards the user in the rear deltoid station. Both stations allow for independent (one arm at a time) exercise movement. Connection of two or more exercise stations in a multi-station arrangement can conserve space in a gym and provide for a more orderly arrangement of exercise stations. 
       FIGS. 5 and 6  illustrate another embodiment of a multi-station exercise machine  150  which again has two exercise stations  152 ,  154 , but in this case each station has its own dedicated weight stack in back-to-back weight stack housings  155 ,  156 , respectively. This allows both exercise stations to be in use simultaneously and independently. The first exercise station  152  comprises a seated mid row exercise station with a pivoting user support  158 , while the second exercise station  154  comprises a seated dip exercise station which has a fixed user support  160 , and the stations are positioned in line and facing one another on opposite sides of the double weight stack  155 ,  156 . 
       FIG. 5  illustrates each exercise station  152 ,  154  with a user  162 ,  164  seated on the respective user support and positioned in a start position for the respective exercise, while  FIG. 6  illustrates the end positions of the two exercises. However, the two stations can be used completely independently and a user on one station may be at a different stage in the exercise from a user on the second station. 
     As noted above, the first exercise station  152  is designed for performing mid-row exercises. Station  152  comprises a main frame portion  222  with user support  158  pivotally mounted on the frame. A U-shaped user engagement device or exercise arm  225  with handles  226  at its free, upper ends is slideably mounted on the base  228  of the frame portion  222  via linear slide or carriage  230 . The linear slide  230  is linked to an exercise resistance, in this case a weight stack in housing  155 , via a cable and pulley linkage, most of which is concealed within the weight stack housing, with the cable  234  of the linkage connected to the slide  230  as indicated in  FIG. 6 . The linear slide or sliding wedge  230  is also linked to the underside of the user support  158 , as described in more detail below, and forms part of a connecting linkage which translates movement of the exercise arm into movement of the user support. The sliding wedge linkage between the exercise arm and user support is similar to that described in U.S. Pat. No. 6,916,278, the contents of which are incorporated herein by reference. 
     The main frame portion also has a slightly rearward inclined upright strut  235  at the rear end of base  222 , which has a stop pad  236  at its upper end forming a rest for the user support in the exercise end position of  FIG. 6 , and a pivot mounting post  238  extending upwardly from the base at a position spaced forward from upright strut  235 . The user support  158  is generally L-shaped, and has a base  240  on which a seat pad  242  is mounted, with a pair of foot rests or foot plates  244  secured adjacent the forward end of base  240 , and an upright  245  supporting back pad  246 . A guide bar or track  248  is mounted on the underside of the base  240  of the user support so as to extend at an upwardly inclined angle from the rear end to the forward end. The user support is pivoted to the upper end of pivot mount  238  for rotation about pivot axis  250  located beneath the seat pad  242 . 
     The linear slide or wedge  230  has a lower sleeve portion which is slideably engaged on a pair of parallel, linear guide bars  251  on the base  228  of the frame, and an upper wedge shaped portion comprising spaced parallel plates with a wheel  252  rotatably mounted between the plates at its upper end for rolling engagement on the guide bar or track  248  on the underside of the user support base. The central portion of the U-shaped exercise arm  225  is rigidly mounted on the slide or wedge  230 . Rearward linear motion of the exercise arm is translated into rearward rotational movement of the user support with this arrangement, as described in more detail below. 
       FIGS. 5 and 6  illustrate a user  162  performing a rowing type of exercise, also known as a mid row exercise, on the station  152 . In  FIGS. 5 and 6 , dotted line  255  is the gravitational centerline of the user support pivot  250 , while dotted line  256  represents the orientation of the user support back rest, or the back of the user when seated on the support. To perform the exercise, the user sits on the seat with the user support in the position illustrated in  FIG. 5 , and places their feet on the foot support plates  244  while gripping handles  226  with their arms straight out in front. The user support is initially positioned in a back supported, forwardly inclined position, so that the user&#39;s body is initially at a forward lean of around 13 degrees off vertical. The user&#39;s arms extend straight forwards with their hands slightly below shoulder level, which is similar to the starting position for a free rowing exercise. 
     The user then pulls handles  226  towards their body in a rowing action, simultaneously pulling the slide or wedge  230  along the rails  251 . This wedges the wheel  252  along the angled user support guide bar  248 , rotating the user support rearward about pivot  250 , and moving the user from a slightly forwardly inclined position to a reclined position, ending with their arms pulled back and their hands at a slightly lower elevation, relative to their shoulders, than the starting position, as seen in  FIG. 6 . This follows a natural rearward arcing rowing motion. This exercise machine mimics the slight, naturally arcing movement of the upper body when rowing a boat or exercising on a rowing machine, without allowing the user to bend at the waist, which is undesirable and can occur with a free rowing exercise. 
     In the mid-row station  152  of this embodiment, the user support pivot  250  is positioned directly under the exerciser. The gravitational centerline  255  runs very close to the centerline of the user&#39;s hip, allowing a balanced portion of the user and user support to be positioned on each side of the gravitational centerline in both the start and finish position. Because the user support seat  242  rises upward as it rotates and the exercise arm travels in a straight line, the positioning of the exerciser&#39;s hands, relative to their shoulders, is slightly higher in the starting position than the finish position, and the user support travels through three different position during the exercise, moving from an inclined position through a vertical position into a reclined position at the end of the exercise. This involves more of the back muscles in one exercise, which is not possible with a conventional rowing machine exercise using a cable. 
     The seated dip exercise station  154  is similar to the stand-alone seated dip machine of FIGS. 5 to 8 of co-pending U.S. patent application Ser. No. 10/633,805, the entire contents of which are incorporated herein by reference, except for the fact that the user support  160  in station  154  is fixed, not pivotally mounted. 
     Station  154  has a main frame portion comprising a horizontal base  260  with a rearwardly and upwardly inclined upright strut  262  at its rear end and an upright seat support strut  264  located in front of strut  262  and connected to it via brace  265 . Weight stack housing  156  is connected at the forward end of base  260 . The housing contains a conventional selectorized weight stack. The generally L-shaped user support frame  160  is secured to the upper end of seat support strut  264 . The user support frame  160  has a first or base portion  268  on which a seat pad  270  is mounted, and a second or upright portion  272  on which a back pad  274  is mounted. The user support frame is fixed at a slight forward inclination, as illustrated. A foot rest or footplate  275  is mounted on the base of the frame, rather than on the user support frame, at a position in front of the forward end of the base portion  260 , such that a user can easily rest their feet on the footplate when seated on the seat pad  270  in a forward lean. 
     An exercise arm assembly or user engagement device  276  is pivotally mounted at the upper end of the upright strut  262  so as to extend forwardly on opposite sides of the user support frame. Arm assembly  276  has a pair of parallel plates  278  pivotally mounted on opposite sides of upright strut  262  via a pivot pin for rotation about pivot axis  280 . A U-shaped exercise arm has a central section secured to plates  278 , and opposite arms  282  projecting forwardly from plates  278  on opposite sides of the user support frame, with user engaging portions or hand grips  284  at the forward ends of arms  282 . The plates  278  extend rearward from upright strut  262  and are linked to the weight stack at their rear ends via a cable and pulley assembly  285  having a cable  286  extending from an anchor  288  on the rear of strut  262 , around a pulley mounted between the rear ends of the plates, then around pulleys  290 ,  292  on the main frame before running through the base section  260  of the main frame into the weight stack housing where it extends over further pulleys (not visible in the drawings) before linking in any conventional manner with the weight stack. 
       FIGS. 5 and 6  illustrate the user  164  performing a bar dip type of exercise, with  FIG. 5  illustrating the starting position and  FIG. 6  illustrating the finish position. In a free bar dip exercise, a user grips two parallel bars on opposite sides of their body. They then pull themselves into a position in which their arms and knees are bent while leaning slightly forwardly for balance. In the starting position of a dip exercise on station  154  of this embodiment, the user  164  sits on the seat and places their feet on the footplate  275 , and grabs the handles  284  on each side, as illustrated in  FIG. 5 . The fixed user support places the user into a slightly forwardly inclined position, with their hands slightly below their shoulders and their arms and legs bent. This closely mimics the starting position of a free bar dip exercise. 
     The user  164  then pushes the exercise arm assembly  276  downwards about pivot axis  280  until their arms are straight down and aligned with the sides of their body, as indicated in  FIG. 6 . Pushing the handles of the exercise arm down causes the rear ends of plates  278  to raise, pulling on the weight bearing cable  286  and providing exercise resistance. The exercise ends with the user&#39;s arms extending straight down the side centerline of their body in the finish position. Because the user is fully supported and not suspended, as they would be in a free bar exercise, the handles  284  can be angled to provide a more comfortable starting and finishing hand position with less extreme bending to the wrist than would be encountered in a free bar dip exercise. 
       FIGS. 7 and 8  illustrate a multi-station exercise machine  300  which combines two plate-loaded exercise stations  302 ,  304  positioned back-to-back. In this embodiment, both exercise stations have rocking seats with user engagement devices and a connecting linkage which translates movement of the user engagement device to movement of the rocking seat. The first station  302  is a chest press exercise station and the second station  304  is a leg press station, but other plate loaded exercise stations may be positioned back-to-back in a similar manner in alternative embodiments. The stations have separate loads or exercise resistance, and can be in use simultaneously and independent from one another, as in the previous embodiment. 
     The two stations  302 ,  304  have main frame assembly with a common base portion  305  supporting both stations and having an upright strut  306  located between the two stations. Each station is shown with a user  308 ,  310 , respectively, positioned on the station, with the exercise start position illustrated in  FIG. 7  and an exercise end position illustrated in  FIG. 8 . 
     Chest press station  302  may be used to perform a bench press type exercise similar to a free weight barbell bench press. The chest press station  302  of this embodiment is the same as the stand-alone chest press machine illustrated in FIGS. 13 to 16 of application Ser. No. 10/633,805 cited above, the contents of which are incorporated herein by reference, apart from the fact that the station shares a common main frame with one or more additional exercise stations. Chest press station  302  duplicates the movement carried out by an exerciser when performing a chest press or bench press with a free barbell or dumbbell, but is easier and more comfortable since the user&#39;s movement is guided while the user&#39;s body is filly supported throughout the exercise. 
     Chest press station  302  of this embodiment has a user support frame  312  pivotally mounted on the main frame, a user engagement device or exercise arm assembly  314  pivotally mounted at the upper end of upright  306  of the main frame, a connecting link  315  between the exercise arm and the user support frame, and an exercise resistance, which in this case comprises weight plates  316  mounted on weight receiving pegs  318  at the forward end of the user support frame. A stop post  320  on the base portion  305  of the main frame supports the user support frame in the start position. 
     The user support frame  312  is generally L-shaped with a base  322  on which a seat pad  324  is adjustably mounted, and an upright  325  on which a back pad  326  is mounted. A footrest or foot plate  328  is secured beneath the base at an appropriate position and orientation for supporting the feet of a user seated on the seat pad. The weight plates  316  are positioned forward of the footrest  328 . The frame  312  is pivotally supported on a pivot mount  330  on the main frame for rotation about pivot axis  332  which is located on the upright  325  of the user support frame adjacent the junction between the upright and base  322  of the frame. Pivot mount  330  is supported on a brace member  334  which extends between the base  305  and upright strut  306  of the main frame. 
     The exercise arm exercise arm assembly  314  comprises a U-shaped member with a central section secured to pivot bracket or pivot plates  335  which are pivoted to the upper end of the upright  306  and to the upper end of connecting link  315 , as described below. Opposite exercise arms or arm portions  336  of the U-shaped member extend on opposite sides of the user support. A pair of downwardly directed handles  338  are mounted at the forward ends of arms  336  for gripping by a user with their hands in a suitable orientation for performing a chest press exercise. Pivot bracket  335  is pivoted at one position to the upper end of upright  306  via pivot  340 , and at another position to the upper end of connecting link  315 , via pivot  342 . The lower end of the connecting link is pivoted via pivot  344  to a pivot bracket  345  at the lower end of the user support upright  325 , so that upward rotational movement of the exercise arm results in rearward rotational movement of the user support. 
     In an alternative arrangement, a single or two-part exercise arm may be adjustable in order to vary the start position for user&#39;s with different arm lengths. The bracket or plate  335  may be replaced with one or two range-of-motion or ROM plates, and each exercise arm may be releasably secured to the ROM plate, at a selected angular position. In this case, the arm is pivoted to the ROM plate, which has a series of spaced openings extending in a part circular path. The arm is secured at a selected angular orientation relative to the plate by a releasable push pin or the like extending through a selected opening. A ROM arrangement for an adjustable exercise arm is described, for example, in U.S. Pat. No. 6,090,020 of Webber, the contents of which are incorporated herein by reference. 
     The user  308  first sits on the seat  324  in the start position of  FIG. 7 , resting their feet on footrest  328  which rests on stop member  320  in the start position, and grabbing the handles  338  with their hands. The user starts the exercise in a slightly reclined position, with their hands slightly below their shoulders and slightly in front of, and in line with, their chest. This mimics the start position for a barbell bench press. Pushing the exercise arm forwards into the position of  FIG. 8  pushes the connecting link  315  downward, which in turn pushes the user support, causing it to rotate rearward about its pivotal connection  332  to the main frame. The exercise arm and user are rotated during the exercise to produce an exercise path with approximately 10 degrees of arc. This moves the user from a slightly reclined position to a substantially reclined position, ending with their arms extending straight forward and their hands at a slightly higher position relative to their shoulders, as compared with the start position. As indicated in  FIG. 8 , the user&#39;s arms in the end position are angled slightly upwardly with respect to a line perpendicular to the back pad  326 . This end position mimics the end position for a free barbell bench press, and substantially mimics the slight, natural arcing movement the arms go through in the “chest to chin” movement of a free barbell bench press. 
     In the chest press station  302  of  FIGS. 7 and 8 , the connecting link  315  pushes the user support to cause it to rotate rearward. The vertical dotted line  350  in  FIGS. 7 and 8  indicates the vertical gravitational centerline of the user support pivot axis  332 , which is the gravitational centerline of the user performing the exercise. The position of pivot axis  332  places the centerline  350  rearward of the user&#39;s hips and in line with the user&#39;s shoulders in the start position of  FIG. 6 . Thus, the majority of the user starts the exercise in a position forward of the centerline  350 , and the user&#39;s body rotates rearwardly through the centerline throughout the exercise, finishing with the centerline  350  extending through their torso for a more evenly balanced weight distribution at the end of the exercise. The combined movement of the user support and exercise arm produces around a ten degree rise in hand position from start position, which is similar to the natural arcing pattern of the free barbell bench press exercise, which has the bar traveling in a “chest to chin” exercise motion. At the same time, the exercise station is more comfortable and easier for an inexperienced exerciser, guiding the user throughout the movement to follow the desired exercise path. 
     In the chest press exercise station  302 , the seat pad  324  comprises a primary user support which is adjustable via post  352  which is telescopically engaged in tube  354  mounted on the base  322  of the user support frame. Post is secured in a selected position in tube  354  via a pop pin or lock device, depending on the seat height desired by the user. The back pad  326  comprises a secondary user support, and the foot plate  328  provides an additional user support which travels with the user support frame during an exercise movement. This station has a single, rigid connecting link  315  which translates movement of the pivotally mounted exercise arm into movement of the user support, and the exercise arm and user support both travel in the same direction, rearward about their respective pivot axes. 
     The leg press station  304  of machine  300  is designed for performing squat type leg press exercises with the user in a prone or supine position at the start of the exercise, as illustrated in  FIG. 7 .  FIG. 8  illustrates the end position of the exercise, with the user&#39;s torso inclined upwardly relative to the start position of  FIG. 7 . The leg press station is similar to the stand alone leg press machine of FIGS. 21 to 24 of co-pending application Ser. No. 10/633,805 referenced above, the contents of which are incorporated herein by reference, except that the weight stack is replaced by hand loaded weight plates, as described in more detail below. 
     Leg press station  304  has a user support frame  355  pivotally mounted on the main frame, and a leg exercise arm  356  which has a lower end pivoted to a downwardly directed portion at the forward end of the user support frame  355  for rotation about a first pivot axis or first pivot connection  358 . The leg exercise arm has a user engaging foot plate  359  at its upper end. An upwardly inclined pivot mount portion  360  is mounted on the base  305  of the main frame, and the user support frame is pivotally connected to an upper end of the pivot mount portion  360  for rotation about a second pivot axis  362 . A connecting linkage  364  is pivotally connected to the exercise arm  356  at a location spaced above first pivot axis  358  for rotation about a third pivot axis  365  (see  FIG. 8 ), and is pivotally connected to the base portion  305  of the main frame for rotation about a fourth pivot axis  366 , so that forward rotational movement of the arm  356  results in upward rotational movement of the user support. In the illustrated embodiment, the connecting linkage is a single rigid link, but it may comprise more than one part in alternative embodiments. 
     The user support frame  355  is generally Y-shaped, with an upper support member  375  and a lower support or strut  372  extending rearward at an angle to the upper member. The upper support member  375  has a downwardly curved portion at its forward end which is pivotally secured to the lower end of the exercise arm at pivot axis  358 , as described above. A brace  376  extends between the upper and lower supports  375 ,  372  at an intermediate point in their length for added support. The exercise resistance in this embodiment comprises weight plates  368  mounted on pegs  370  at the end of the lower support strut  372 . Other moving parts of the machine may be linked to the exercise resistance in alternative embodiments, and other types of exercise resistance may be used in place of the weight plates. A support post or stop  374  on the base section of the frame beneath the user support frame engages the lower support strut  372  in the exercise start position, as illustrated in  FIG. 7 , so as to provide a stop for the user support frame before the user commences an exercise. 
     A primary support back pad  378  is mounted on the upper support  375  of the user support frame. A secondary support assembly comprising head rest  380 , two shoulder pads  382 , and two hand grips  384 , is mounted at the rear end of the upper support. A user reclining on the back pad can place their feet on foot plate  359 , as indicated in  FIGS. 7 and 8 . The connecting linkage  364  is located beneath the user engaging part of the user support in at least the start position of a leg press exercise, as seen in  FIG. 7 . 
     The secondary support assembly is adjustably mounted on the upper support via sliding mount, and secured in a selected position via a spring loaded pull pin  385 . Handle  386  is provided for adjusting the position of the secondary support assembly. This permits the spacing between the secondary support assembly and foot plate  359  to be adjusted for users with different leg lengths. 
       FIGS. 7 and 8  illustrate a user  310  performing a squat type or lying leg press exercise on the station  304 . The user first lies on the back pad with the machine in the start position of  FIG. 7 , with their shoulders braced against the shoulder pads  382 , and places their feet on the foot plate  359 , adjusting the position of the secondary support assembly if needed. They then push the foot plate  359  forward. While performing the exercise, the user may also grab the handles  384  for added stability. The starting position of  FIG. 7  places the user in a substantially horizontal, back supported position with their legs bent, thighs against the torso, and knees aligned with the toes. This corresponds to the squatted position of a free barbell squat exercise, without the difficulty in balance and coordination in reaching this position when standing. The vertical dotted line  390  in  FIGS. 7 and 8  represents the vertical centerline extending through the user support pivot axis  362 , which is also the gravitational centerline of the user performing the exercise. 
     As indicated in  FIG. 7 , the user support backrest  378  starts at an angle of around 90 degrees to the vertical centerline  390 , i.e. in a horizontal or substantially horizontal orientation. When the exercise arm  356  is pushed forward by the user pushing against the foot plate  356 , rotating about pivot axis  358 , the connecting link  364  pulls the pivot connection point between the exercise arm and user support at pivot axis  358  downward and rearward, which in turn forces the user support  355  to rotate about pivot axis  362  in the same direction as the exercise arm. This also moves the user from a horizontal to an upwardly inclined orientation, with their legs straight out and slightly angled to the upper torso, and resistive force directed up the legs to the hips. This is similar to the standing position of a standing squat exercise, but with the slight angle of the user&#39;s torso taking pressure off the lower back. This exercise therefore closely mimics the movement of a standing squat type exercise, but reduces the risk of strain to the exerciser&#39;s lower back, since the resistive force directed to the hips and the back is properly supported. This eliminates or reduces spinal compression and improper lower back arching, providing a safer, more comfortable exercise. 
     The connecting linkage joins the exercise arm to the main frame, and the exercise arm is pivotally mounted on the user support. Thus the exercise arm is mounted to, and travels with, the user support. However, it is still directly linked to the main frame via the connecting link. This linkage connection controls the movement of the exercise arm and ultimately the movement of the user support, maintaining the automatic and continuous adjustment and alignment between the user support and exercise arm. 
     The user support pivot  362  is positioned directly under the exerciser and the gravitational centerline  390  extending through pivot  362  runs very close to the centerline of the user&#39;s hips in the start position of  FIG. 7 , allowing a balanced portion of both the user support and exerciser to be positioned on each side of the gravitational centerline. At the end of the exercise, the user is raised to approximately 61 degrees to the vertical with a portion of the weight of the user support and user on opposite sides of vertical gravitational center line. As illustrated in  FIGS. 7 and 8 , a substantial portion of the combined weight of the user and the user support frame is positioned on each side of the gravitational center line  390  of the user support pivot axis in both the start and end position. The combined weight of the user and user support has a reduced effect on the amount of starting resistance, since part of the weight of the user and the user support is rearward of the user support pivot in the start position, acting as a counterbalance to the exercise arm. Because only a portion of the user and user support frame passes through the gravitational center line  390  during the exercise, a major drop off in resistance is not felt by the user during the exercise. 
     In the exercise station  304 , the exercise arm is pivoted directly to the user support and the connecting linkage pivotally links the exercise arm to the frame such that rotational movement of the arm results in rotational movement of the user support. The user support has a primary user support or back pad  378 , a secondary user support (head support pad and shoulder pads), and an additional user support comprising hand grips  384 , all of which remain in the same relative positions throughout the exercise movement. 
     In each of the exercise stations  302  and  304  of  FIGS. 7 and 8 , a connecting linkage translates movement of the user engagement device to the user support. The connecting linkage may be movably engaged with at least two of the main frame, user engagement device, and user support. Additionally, the exercise resistance in both stations is provided by hand loaded plates. In each station, at least one user support portion is adjustable, with the seat pad  324  being adjustable in the chest press station  302 , and the shoulder pads of the secondary support being adjustable in the leg press station  304 . In both cases, the connecting link is a single, rigid connecting link, although multi-part connecting linkages may be provided in alternative embodiments. In both stations, the exercise arm travels in the same direction as the user support, specifically rearward in the chest press station and forward in the leg press station. 
       FIGS. 9 to 15  illustrate another embodiment of a multi-station exercise machine  400 , in which three exercise stations  402 ,  404 , and  405  each associated with its own weight stack housing  406 ,  407 , and  408 , respectively. The weight stack housings are secured together by angle brackets  410  between the weight stack housings, as illustrated in  FIG. 9 . The main frame assembly in this embodiment comprises the weight stack housings  406 ,  407 , and  408  and separate main frame portions  420 ,  470 , and  550  supporting the components of the respective exercise stations, as described in more detail below. In this embodiment, the stations comprise a shoulder press exercise station  402 , a chin up exercise station  404 , and a leg press exercise station  405 , although different exercise stations from co-pending application Ser. No. 10/633,805 referenced above may be used in place of stations  402 ,  404  and  405  in alternative embodiments. The leg press station  405  is substantially identical to the leg press station  304  of the previous embodiment, and like reference numerals are used for like parts as appropriate. However, unlike leg press station  304 , the exercise resistance in this embodiment is provided by a weight stack in housing  408 . 
       FIG. 9  illustrates the three exercise stations secured together in machine  400 , while  FIGS. 10 to 15  illustrate the individual stations in more detail.  FIGS. 10 and 11  illustrate the shoulder press station  402  in an exercise start and end position, respectively, with a user  412  seated at the station and performing a shoulder press exercise. The shoulder press exercise station  402  is similar to the stand alone shoulder press exercise machine illustrated in FIGS. 9 to 12 of co-pending application Ser. No. 10/633,805, the contents of which are incorporated herein by reference, except that the exercise resistance is linked to the connecting link in that machine, whereas the exercise resistance in station  402  is linked to the pivoted user support, as described below. 
     The shoulder press station  402  is designed to be similar to a free weight overhead press exercise, while reducing or eliminating the disadvantages of a free weight exercise, i.e. balance, coordination, and strength to follow the proper movement path, and possible injury if the proper movement is not followed. Shoulder press station  402  constrains the user to follow the proper exercise path, while fully supporting the user&#39;s body throughout the exercise for comfort and safety. 
     As illustrated in  FIGS. 10 and 11 , exercise station  402  basically comprises a main frame  414 , a user support frame  415  pivotally mounted on the main frame, an exercise arm  416  pivotally mounted on the main frame and linked to the user support frame by a connecting link  418 , and an exercise resistance such as selectorized weight stack in housing  406  linked to the user support frame. The main frame  414  comprises a horizontal base section  420 , a rearwardly inclined upright section or strut  422 , and a pivot mount section  424 . The user support frame  415  is generally L-shaped with a base  425  on which a seat pad or primary user support  426  is adjustably mounted, and an upright  428  on which a back pad or secondary user support  430  is mounted. A foot plate or footrest  432  is secured to the forward end of the base  425  and provides an additional user support which supports a spaced portion of the user&#39;s body. 
     The user support frame  415  is pivotally mounted on the pivot mount section  424  of the main frame for rotation about a pivot axis  434  located close to the junction between the base and upright sections of the user support frame, so that the pivot is positioned directly under the exerciser. The seat pad  426  is mounted on a strut or post  435  which is telescopically engaged in tube  436  on user support base  425  to allow the height of the seat pad relative to the frame to be adjusted. A stop  438  on the main frame adjacent the forward end of the user support frame acts to support the user support frame in the starting position of  FIG. 10 . 
     The exercise arm  416  comprises a first member or strut  439  having one end pivoted to the top of rear frame strut  422  for rotation about pivot axis  440 , and a U-shaped member  442  which has a central section  443  secured to the opposite end of strut  439  and opposite handle arms  444  extending on opposite sides of the user seat, with user engaging hand grips  445  at the ends of arms  444 . The connecting link  418  between the exercise arm and user support comprises an arm or link  419  having a first end pivoted to an intermediate point on strut  439  for rotation about first pivot axis  446  and a second end pivotally secured to a slide member  448  for rotation about second pivot axis  450 . The slide member  448  is slideably mounted on a rail or guide bar  452  mounted on the rear of the user support upright  428 . The sliding linkage mechanism between the exercise arm and user support frame is similar to that described in U.S. Pat. No. 7,052,444 of Webber, the contents of which are incorporated herein by reference. 
     The base  425  of the user support frame is linked to the exercise resistance or weight stack via a cable and pulley linkage  454 . A cable  455  extends from an anchor  456  on the base  420  of the main frame, over a pulley  457  mounted on the base  425  of the user support, back over a pulley  458  on the base  420  of the main frame in front of anchor  456 , and then through the frame and into the weight stack housing  406 , where it is linked to a selectorized weight stack in a conventional manner. 
       FIGS. 10 and 11  illustrate a user  412  performing a shoulder press exercise on the shoulder press station  402 . To perform the exercise, the user sits on the seat in the start position of  FIG. 10 , where the seat is in a slightly rearward reclined position. The user places their feet on the foot rest  432 , and grabs the handles  445 . In  FIGS. 10 and 11 , the dotted line  460  represents the gravitational centerline which extends through the user support pivot axis  434 , which is the gravitational centerline of the user performing the exercise. As can be seen in  FIG. 10 , the start position places the user in a slightly reclined position, at an angle of around 22 degrees, with their hands at approximately shoulder level and forward of the side centerline of their body. This is equivalent to the start position of the user&#39;s body for a free weight shoulder press. 
     From the position of  FIG. 10 , the user pushes the handles upwards, rotating the exercise arm rearwardly about pivot axis  440 . At the same time, the exercise arm pulls the connecting link  418  upward and rearward, which in turn forces the linear slide member  448  upwards and causes the user support to rotate rearwards about pivot axis  434 . Additionally, upward movement of the base of the user support lifts the selected weights in the weight stack via the cable and pulley linkage  454 . The user is placed in a back supported position with their hands slightly forward of the shoulders in the start position, and then follows the slight natural arcing movement of a barbell press, finishing the exercise in a substantially reclined position of around 46 degrees to the gravitational centerline, with their arms fully extended and in line with the side centerline of their body, as illustrated in  FIG. 11 . This substantially mimics the finish position of a free weight shoulder press exercise. The exercise movement is therefore similar to the slight, natural arcing movement the arms go through when performing a barbell or dumbbell free weight shoulder press exercise. 
     In this station, the position of the user support pivot axis  434  beneath the user&#39;s body distributes the weight of the user&#39;s body and the support frame on both sides of the gravitational centerline  460  in both the start and end position of the exercise. The starting position in this case places the user support pivot axis  434  rearward of the exerciser&#39;s hips, with the gravitational centerline  460  at or close to alignment with the centerline of their shoulders. The majority of the user&#39;s body starts forward of the gravitational centerline and the user rotates rearwards through this centerline during the exercise, and finishes with the centerline extending through their torso for a more evenly balanced distribution of weight at the end of the exercise, as illustrated in  FIG. 11 . The combined weight of the user and user support has a reduced effect on the amount of starting resistance, since part of the user&#39;s weight is still placed rearward of the user support pivot, acting as a counterbalance to the exercise arm. By the same token, as the user passes rearward through the gravitational centerline, there is no appreciable drop off in resistance felt because of the amount of weight which still remains forward of centerline  460 . 
     The user  412  seated on the user support  415  in station  402  is fully supported throughout the exercise movement so that they do not have to worry about balance and coordination, unlike a free weight exercise. The exercise arm and user support are linked to one another to self-align throughout the exercise movement, so that the handles can be angled for a more comfortable start and finish position. 
     The chin up or pull down station  404  is illustrated in  FIGS. 12 and 13 , and is designed to allow a user to perform chin up type exercises similar to the free body weight exercise performed by a user pulling themselves up from the ground while gripping an overhead bar or “chinning” bar, with the user raising their body until their chin touches the bar. The exercise carried out at station  404  produces user start and end positions similar to the natural body alignment in the start and finish positions of a free body weight chin up exercise. The chin up station  404  is similar to the stand alone chin up or pull down machine illustrated in FIGS. 1 to 4 of co-pending application Ser. No. 10/633,805, the contents of which are incorporated herein by reference. 
     Station  404  has a main frame having a horizontal base section  470  which is secured to the lower end of weight stack housing  407  at its forward end, an upper strut  472  projecting horizontally from an upper part of housing  407 , and a rearwardly inclined upright strut  474  extending upwardly from the base section  470  to a rear end of the upper strut  472 . 
     A generally T-shaped user support frame  475  is pivotally mounted on the base section via a four-bar pivot linkage  476  between the base section  470  and the user support frame. The user support frame  475  has a base portion  478  and an upright member  480  projecting upwardly from an intermediate position on base portion  478 . A seat pad or primary support  482  is mounted at the rear end of base portion  478 , behind upright member  480 . At least one secondary or additional support is also mounted on the user support frame. In this embodiment, one secondary or additional support comprises a pair of roller pads  485  on a strut which is telescopically mounted in member  480 . The position of the roller pads  485  can be adjusted by moving the strut up or down and then securing it in position via a spring loaded pull pin (not visible in the drawings). Another secondary support comprises a foot rest  484  mounted at the forward end of base portion  478 . 
     An exercise arm assembly or user engagement device  486  is pivotally mounted at the top of the upright strut  474  to rotate about pivot axis  488 . The exercise arm assembly comprises a generally U-shaped exercise arm  490  having a central portion  491  secured to a strut  492  which projects generally forward from arm  490 . A pivot mounting bracket or pair of pivot plates  494  is secured to strut  492  and pivoted to the upper end of upright strut  474  for rotation about pivot axis  488 . The forward end of strut  492  is linked to the weight stack in housing  407  via a cable  495  extending from anchor  496  on the horizontal strut  472 , over a pulley  497  secured between mounting plates  498  at the end of strut  492 , then back around pulley  499  on strut  472  and via additional pulleys (not visible in the drawings) to the top of the weight stack. A U-shaped handle bar  500  is pivoted to the ends of the U-shaped exercise arm for rotation about pivot axis  502 , and is suspended downwardly from the exercise arm so that the central portion  501  of the handle bar (see  FIG. 9 ) can be gripped by a user with both hands. 
     An adjustable length connecting link  504  pivotally connects the exercise arm assembly  486  to the forward end of the base  478  of the user support frame. The link  504  has a first end pivoted to the pivot mounting bracket or plates  494  of the exercise arm for rotation about pivot axis  505  which is spaced rearward from pivot axis  488 , and a second end pivoted to a pivot mount  506  on the forward end of user support base  478  for rotation about pivot axis  508 . The link  504  comprises two telescopically engaging parts which are secured together at a selected extension via a spring loaded pull pin  510  engaging in a selected opening  512  in one of the telescoping parts. A handle  514  is provided to assist in adjusting the length of connecting link  504 . 
     As noted above, the user support frame  475  is pivotally mounted on base  470  via a four bar linkage assembly  476  comprising a pair of pivoted lever or link arms  515 ,  516  extending between the base  470  of the main frame and the base portion  478  of the user support frame. The first lever arm  515  is pivoted at one end to the forward end of a pivot mount on the base  470  to rotate about a first pivot axis  519 , and to the forward end of base portion  478  at the opposite end, to rotate about a second pivot axis  518 . The second lever arm  516  is pivoted at one end to the rear end of the pivot mount on base  470  to rotate about a third pivot axis  522 , and at the opposite end to the rear end of the base portion  478  to rotate about fourth pivot axis  520 . The four bar pivot linkage defines a theoretical pivot  524  about which the user support frame rotates. 
       FIGS. 12 and 13  illustrate the start and finish positions of a chin up exercise with a user  525  in place on the user support frame  475 . To perform the exercise, the user positions themself in a seated position on seat pad  482 , which starts in a slightly downwardly reclined orientation as illustrated in  FIG. 12 . They then slide their legs under the thigh hold down roller pads  485 , adjusting the position of these pads by sliding the adjustment strut up and down if necessary, and place their feet on the user support footrest or plate  484 . They then grab the handle bar  500  of the exercise arm assembly  486  and pull it downwards. The starting position of  FIG. 12  places the user&#39;s upper body in a slightly forward lean with their arms extending straight overhead, in line with the side center line of their body. If necessary, the user can adjust the distance between the user support seat  482  and exercise arm bar or handle  500  by adjusting the length of connecting link  504 . 
     As the exercise arm assembly moves downwards, rotating about the pivot axis  488  at the top of strut  474 , the connecting link  504  is also pushed down, and pushes the front end of the user support frame  475  downwards, rotating the frame about the four bar linkage into the finish position illustrated in  FIG. 13 , in which the seat pad  482  is moved from a rearwardly reclined to a forwardly inclined orientation. At the same time, the selected weights in the weight stack are lifted via the cable and pulley linkage between the end of exercise arm strut  492  and the weight stack. As the seat pad changes its orientation from a reclined angle to an inclined angle, the user automatically adjusts their upper body position rearward (relative to their angular position on the seat) to compensate for this change in seat angle, and finishes the exercise with their hands below their chin and slightly in front of their shoulders. This slight rearward movement is similar to the natural rearward arc a person&#39;s upper body goes through when performing a free bar chin up. The chin up station  404  provides the user with a safer and more comfortable exercise movement than was possible with previous rigid arm pull down exercise machines. 
     The user support pivot is positioned under the user support frame such that a substantial portion of the combined weight of the user and the user support frame is positioned on each side of the gravitational center line  530  which extends through the theoretical pivot  524  of the four bar pivot linkage  476  in both the start and finish position. Since the pivoting motion is provided by a four bar linkage, the center line  530  is a theoretical center line of the pivotal movement. The portion of both the user and the user support positioned on each side of line  530  varies only very slightly from the start to the end point of the exercise movement, as can be seen in  FIGS. 12 and 13 . This balanced distribution minimizes the effect that the combined weight of the user and user support has on the exercise resistance, while still allowing it to act as a counter balance to offset the weight of the exercise arm. The combined weight of the user and user support frame has little effect on the amount of starting resistance, because a substantially equal amount of weight is balanced rearward of the user support pivot. By the same token, because only a small portion of the user passes through the gravitational center line  530  during the exercise, there is no appreciable drop off in resistance felt by the user. 
     In this embodiment, the user  525  is in a forward lean of approximately 3.5 degrees off vertical in the start position, with their arms fully extended and in line with the body side centerline. At the end of the exercise, as illustrated in  FIG. 13 , the user is reclining at approximately 19 degrees, with their hands positioned under the chin and slightly forward of their shoulders. Thus, the upper body moves through an angle of approximately 22.5 degrees, which is similar to the movement when performing a free chin up exercise with an overhead chinning bar. 
     The primary user support in exercise station  404  is the seat pad  482 , while a secondary support is provided by the thigh hold-down pads  485 . A further support or stabilization means is provided by the foot plate  484  which travels with the user support frame  475 . The multiple user supports help to provide proper positioning of the user relative to the user engaging portion of the exercise arm throughout the entire exercise movement. This also makes the apparatus much more comfortable and natural for the user, making the user want to exercise. The foot plate keeps the user&#39;s feet in the same relaxed and supported position throughout the entire exercise movement. 
       FIGS. 14 and 15  illustrate the start and end positions of a leg press exercise performed on exercise station  405  of  FIG. 9 . The exercise station  405  is substantially identical to the leg press station  304  of the machine  300  of  FIGS. 7 and 8 , and like reference numbers are used for like parts as appropriate. The main difference in station  405  is that the exercise resistance is provided by weight stack in the weight stack housing  408 , rather than hand loaded weight plates as in the station  304 . 
     The leg press station has a main frame with a base portion  550  which is connected to the base of the weight stack housing  408 . As noted above, most of the components of leg press station  405  are identical to those described above in connection with leg press station  304  of  FIGS. 7 and 8 , except that the weight plates  368  at the end of user support lower strut  372  are replaced by a connection to the weight stack in housing  408 . The lower strut  372  of the user support frame  355  in station  405  is linked to the weight stack in housing  408  via a cable and pulley assembly  552  which includes a cable  554  which extends from an anchor (not visible in the drawings) on the base portion of the main frame around a pulley  555  at the end of lower strut  372  of the user support frame  355 , then back to the base portion  550  where it extends around another pulley (not visible in the drawings) and into weight stack housing  408 , where it is linked to a selectorized weight stack in a conventional manner. 
     Operation of leg press station  405  is identical to that described above in connection with station  304  of the previous embodiment, apart from the exercise resistance provided by a selectorized weight stack rather than hand loaded weight plates.  FIGS. 14 and 15  illustrate a user  556  positioned on the user support  355 , with  FIG. 14  illustrating the start position of a squat or lying leg press exercise, and  FIG. 15  illustrating the end position. The exercise movement is exactly the same as described above in connection with leg press station  304  of  FIGS. 7 and 8 . 
     In the multi-station exercise machine of  FIGS. 9 to 15 , each station has its own weight stack, and the stations can be used completely independently of one another. Each station in this embodiment has a pivotally mounted user support and a connecting linkage translates movement of the exercise arm or user engagement device into movement of the user support. However, in alternative embodiments, one or two of the exercise stations may have a fixed user support, as is the case with station  154  of  FIGS. 5 and 6 . Additionally, a greater number of exercise stations my be arranged around a central gang of weight stacks in alternative embodiments, and one or more of the exercise stations  402 ,  404 , and  405  of the illustrated embodiment may be replaced with stations for performing different exercises, such as pec fly, chest press, mid-row, rear deltoid, seated dip, and the like. 
     In the foregoing embodiments, the exercise stations with moving user supports are designed for performing compound exercises which involve more than one muscle or muscle group. However, any of the stations in the foregoing embodiments may be replaced by a station designed for performing isolation exercises designed to isolate and exercise a specific muscle or muscle group.  FIGS. 16 to 24  illustrate a multiple station exercise machine  600  according to another embodiment which has two isolation exercise stations  602 ,  604  connected together in a side-by-side manner, rather than aligned face-to-face or back-to-back as in the previous embodiments of  FIGS. 1 to 8 . The exercise stations  602 ,  604  may alternatively be arranged back-to-back or facing each other in line as in previous embodiments, depending on space requirements, and the aligned stations of  FIGS. 1 to 8  may alternatively be positioned side-by-side in the same manner as in exercise machine  600 . One or both stations may also be combined with two or more additional stations in a radial array arrangement as illustrated in  FIG. 9 , in other alternative embodiments. In other embodiments, either of the exercise stations  602  or  604  of machine  600  may be replaced with any of the exercise stations in the previous embodiments. 
     The first exercise station  602  of  FIG. 16  is a leg extension exercise station which is illustrated in more detail in  FIGS. 17 to 20 . The second exercise station  604  is an arm exercise station, specifically a biceps curl exercise station, and is illustrated in more detail in  FIGS. 21 to 24 . Each of these stations is designed for performing an isolation exercise. A leg extension exercise is an isolation exercise because it involves a single joint, the knee; requires movement of just one body part, the lower leg; and targets a specific muscle group, specifically the quadriceps. A biceps curl exercise is also an isolation exercise which involves a single joint, the elbow, movement of a single body part, the lower arm; and targets a specific muscle group, the biceps. In other embodiments, alternative isolation stations may involve leg curl exercises or triceps extension exercises. 
     As illustrated in  FIG. 16 , the multi-station machine  600  has two weight stack housings  605 ,  606  connected together back-to-back via a connecting strut  608 , and a weight stack in each housing provides exercise resistance or load for the respective isolation exercise stations. This means that the stations can be used independently from one another. The weight stacks of  FIG. 16  may be replaced by other types of exercise resistance such as weight plates or the like in alternative embodiments, for example as illustrated for the multiple station exercise machine of  FIGS. 7 and 8 . The exercise stations  602  and  604  are positioned generally parallel to one another on opposite sides of the central weight stack housings  605  and  606 . 
     Leg extension station  602  is similar or identical to the leg extension machine illustrated in FIGS. 1 to 5 of co-pending application Ser. No. 11/846,472 filed on Aug. 28, 2007, which is referenced above, the entire contents of which are incorporated herein by reference. In alternative embodiments, station  602  may be replaced by any of the other embodiments described in co-pending application Ser. No. 11/846,472 referenced above. As illustrated in  FIGS. 16 to 20 , station  602  comprises a main frame  610  secured to weight stack housing  605 , a user support  612  pivotally mounted on the frame by a four-bar pivoting linkage system  614 , a leg exercise arm assembly  615  pivotally secured to the seat section of the user support, and a connecting link  616  which links movement of the exercise arm to movement of the user support. 
     Main frame  610  has a first section on which the user support and associated components are positioned and a second section which connects the first section to the weight stack housing  605 . The first section has a ground engaging base portion  620  and a rear inclined upright or post  621 . The second section of the main frame  610  connects the first section to the weight stack housing  605  which is positioned on one side of the user support  612 . As illustrated in  FIG. 16 , the second section comprises a lower connecting strut  622  which extends transversely from base portion  620  and is connected to the base of the weight stack housing, and an upper connecting strut  624  which is connected to upright  621  at one end, and to the rear of the weight stack housing  605  at the other end. 
     The user support frame  612  has a base portion  625  with a seat pad  626  and support handles  628  fixedly attached to the base portion. A back rest support strut  630  is pivotally attached to the rear end of the base portion  625  and extends generally upwardly from the base portion, and a back pad  634  is mounted in front of strut  630 . A range-of-motion (ROM) adjustment device  635  is connected between the base portion  625  and back rest support strut  630  for varying the back rest angle and locking the back rest in the adjusted position, as explained in more detail in co-pending application Ser. No. 11/846,472 referenced above, and reference is made to that application for a detailed description of the adjustment device  635 . The back rest adjustment allows adjustment of the back supported positioning for various size users. Adjustment handle  637  linked to the ROM adjustment mechanism allows the user to adjust the back rest position. An “L” shaped outrigger tube  638  extends from seat base portion  625  to one side of the seat. One end of the outrigger tube  638  is attached to the seat base portion or strut at the rear of seat pad  626 , as best illustrated in  FIG. 16 , while the second, outward projecting end has a pivot bracket assembly  640  attached at its end. 
     The four-bar pivot linkage system or pivot assembly  614  between the main frame and seat frame comprises a first pivot link  660  and a second pivot link  662  each pivoted at one end to the main frame and at the other end to the user support frame. The first pivot link  660  is pivotally attached at one end to the rear upright  621  for rotation about pivot axis  664  and pivotally attached at its second end to the rear end of the user support base portion or seat support tube  625  for rotation about pivot axis  665 . As described in U.S. patent application Ser. No. 11/846,472 referenced above, the first pivot link  660  comprises two plates connected together at a central region by shaft  666 . 
     The structure of the second pivot link  662  of the four-bar linkage system  614  is also described and illustrated in more detail in U.S. patent application Ser. No. 11/846,472, and comprises a multiple part assembly pivotally connected at one end between two base struts of the main frame base  620  to pivot about pivot axis  668 , and pivotally connected at the other end to user support base portion  625  to pivot about pivot axis  670 . 
     The exercise arm  615  is also described and illustrated in more detail in U.S. patent application Ser. No. 11/846,472 referenced above, and comprises a main tube  672 , a user engaging device  674  extending to one side of the main tube  672 , and a stand-off tube (not visible in the drawings). The main tube  672  rotates about first exercise arm pivot axis  675  via a pivot bracket assembly or housing  640  at one end. The user engaging device  674  comprises a pad mounting tube  676  with a leg engaging roller or pad  678  telescopically mounted over tube  676 . A pair of connecting brackets are secured approximate the free end of tube  676  and are pivotally connected to the main tube  672  to rotate about second exercise arm pivot axis  680 . This pivotal connection enables the leg engaging pad  678  to self-align to the user during the exercise and automatically adjust to the user&#39;s leg length. 
     The connecting link  616  comprises a pair of spaced bars  682  connected together by connecting bars or tubes. A first end of the connecting link is pivotally attached at or adjacent the front end of the base portion  620  for rotation about a first connecting link pivot axis  684 . A second end of the connecting link extends into the space between the opposite sides or plates of pivot bracket assembly  640  and is pivotally attached to a link connecting pivot mount or sleeve at the end of exercise arm stand-off for rotation about a second connecting link pivot axis which is hidden between the plates of pivot bracket assembly  640 . A shield plate or cover  685  extends over the pivot bracket assembly  640  to form a housing or enclosure which restricts access to the moving parts and protects the user&#39;s fingers. 
     In this exercise station, the user support is pivotally mounted to the main frame via the user support four-bar linkage pivot system, with the first and second pivoting links connecting the first and second pivot mounts on the main frame and user support respectively. The exercise arm is pivotally connected by its first pivot mount to the pivot bracket assembly  640  mounted on the user support outrigger tube  638 . The connecting link  616  pivotally joins to the exercise arm  615  with the main frame via the link connecting pivot mounts. 
     A cable and pulley system links the weight stack in housing  605  to a cam on the rear of the exercise arm main tube  672 . The cable  687  of the cable and pulley system (see  FIGS. 19 and 20 ) is linked to an anchor on exercise arm  672 . The cable and pulley system includes a pulley  688  on outrigger tube  638  and a pulley  690  on the base  620 , respectively. However, different cable and pulley paths may be provided in alternative embodiments. 
       FIGS. 17 and 19  illustrate the start position for a leg extension exercise, with  FIG. 19  illustrating a user  700  seated on the user support ready to perform the exercise. In the start position, the user sits on the seat with their back against the back pad, their knees bent and their feet behind the leg engaging roller  678 , as illustrated in  FIG. 19 . They may grab the support handles  628  for additional bracing if desired. The user then starts the exercise movement by extending their lower legs outward. This movement causes the exercise arm  672  to pivot about pivot axis  675  at its connection to the user support pivot bracket assembly  640 , which simultaneously rotates the stand-off rearward. As the stand-off rotates rearward, it causes the connecting link  616  to rotate rearward as well, as it pivots about its pivotal connection to both the exercise arm and the main frame. This in turn forces the user support to rotate, tilting it rearward about the user support four-bar pivoting linkage system  614 , so that the rear end of the set pad rotates down and the front end rotates up. This means that the hips of a user seated on seat pad  626  drop down while their knees move up when moving from the start position of  FIG. 19  to the end position of  FIG. 20 . 
     The four-bar pivoting linkage system is designed to control the upward and rearward movement of the user support seat and to reorient the seat from a relatively flat start position to an angled end position as illustrated in  FIGS. 18 and 20 . By using the four-bar linkage as the user support pivot system, all the pivoting action can take place under the user with the pivot mounts conveniently located on the main frame and user support. However, the theoretical pivot or combined pivot point of the four-bar linkage system is actually located elsewhere. The theoretical pivot is the point where a single pivot would have to be located in order to mimic the same user support movement pattern achieved by the four-bar pivoting linkage. 
       FIGS. 19 and 20  illustrate the location of the theoretical pivot  702  of the four-bar pivoting linkage system  614 . An explanation of how the theoretical pivot axis of the multiple pivot linkage can be calculated is provided in U.S. patent application Ser. No. 11/846,472 referenced above, and is therefore not explained in detail here. Briefly, the centerline of the arcing movement of each of the pivot links  660 ,  662  between the start and end position is plotted and the point in space where the two centerlines intersect is the theoretical pivot point  702 . Vertically bisecting this point produces the gravitational centerline  704  of the user support movement. As can be seen in  FIGS. 19 and 20 , the gravitational centerline extends through the user support (and user) in each of the start and finish positions of the exercise. The majority of the user&#39;s body starts forward of the gravitational centerline and the user rotates rearwards through this centerline during the exercise, and finishes with the centerline extending through their torso for a more evenly balanced distribution of weight at the end of the exercise, as illustrated in  FIG. 20 . This produces similar advantages to those described above in connection with the rocking seat exercise stations of the previous embodiments. 
     The advantage of the four-bar pivot system with the theoretical pivot is that it duplicates the movement pattern of a single point pivot that might normally be located in an area impossible to access due to either structural or user interference, so that a desired movement pattern may be achieved while keeping the moving parts of the pivot mount beneath the user support. The combined exercise arm and user support movement illustrated in  FIGS. 17 to 20  may not be possible with a single pivot. 
     The leg extension exercise station  602  has a relatively flat seat in the starting position of  FIGS. 17 and 19 , and the starting seat height is relatively low to the ground to make entering, position adjustment and exiting easier. As soon as the exercise arm is engaged, the seat starts to recline to maintain the beginning pre-stretch and continues to recline as the leg exercise arm  672  is extended upward and the user straightens their legs. The finishing position is not severely angled so that the user can achieve a full extension to their legs. Because the seat angle starts out relatively flat and gradually reclines, there is little or no undue stress placed on the knee during the exercise. 
     The pivoting action of the seat drops the user&#39;s hips while it raises their knees, and the user tends to stay firmly planted in the user support. There is no need for any extra hold down support because there is little or no teeter-totter effect with the hips trying to lift up off the seat. Instead, the pivoting seat is continuously moving the user hips in the opposite or downward direction from the legs. In this isolation exercise machine, the pivoting joint of the user (in this case the user&#39;s knee) is substantially aligned with pivot axis  675  of the leg exercise arm throughout the exercise, as seen in  FIGS. 19 and 20 . 
     The combined exercise arm and user support movement of the isolation leg extension exercise machine is made possible by the four-bar pivoting linkage system  614 , which duplicates the movement pattern of a single point pivot that would otherwise be located beneath the machine, as illustrated in  FIGS. 19 and 20 . 
     As illustrated in  FIG. 16 , the arm or biceps curl exercise station  604  is mounted on the opposite side of the multi-station exercise machine to the leg exercise station  602 . The biceps curl exercise station  604  is illustrated in more detail in the side elevation views of  FIGS. 21 and 22 , which illustrate exercise start and end positions, while  FIGS. 23 and 24  illustrate the same positions with a user  700  performing a biceps curl exercise on the station.  FIGS. 21 and 23  illustrate an exercise start position, while  FIGS. 22 and 24  illustrate an exercise end position. The station  604  is also shown in the exercise end position in  FIG. 16 . 
     Biceps curl station  604  is similar or identical to the stand-alone biceps curl machine illustrated in FIGS. 1 to 5 of co-pending application Ser. No. 11/848,012 filed on Aug. 30, 2007, which is referenced above, the entire contents of which are incorporated herein by reference. Reference is made to that application for any details of the biceps curl station not described in detail herein. In alternative embodiments, station  602  may be replaced by any of the other embodiments described in co-pending application Ser. No. 11/848,012 referenced above, including triceps extension stations and convertible biceps curl/triceps extension stations. Station  604  has a main frame  712  attached to the weight stack housing  606 , a user support frame  714  pivotally mounted on the frame via a pivot mount  715 , and an exercise arm assembly  716  pivotally mounted on the user support frame and linked to the main frame via a pivoting connecting link  718  (see  FIG. 22 ) so that movement of the exercise arm assembly results in pivoting movement of the user support. The user support frame  714  is linked to a weight stack  720  mounted in weight stack frame or housing  606  via a cable and pulley linkage  724 . 
     The main frame  712  has a base section or strut  725  having a ground-engaging pad or foot  726  at each end, a transverse guide tube  728  (see  FIG. 16 ) extending between the strut  725  and the base of weight stack frame  606 , a first upright strut  730  at the forward end of base strut  725 , and a rearward inclined, upright post or stand-off  732  at an intermediate point in the length of the strut. Pivot mount or bracket  715  is mounted at the upper end of post  732 . A connecting rod  733  extends between forward strut  730  of the main frame and the rear side of the weight stack housing  606 , as illustrated in  FIG. 16   
     User support frame  714  has a seat support comprising a generally upright rear tube  734 , a generally upright forward tube  735 , and a cross bar or pivot mounting bar  736  extending between tubes  734  and  735 . A seat pad  738  is adjustably mounted at the upper end of the rear tube  734  via seat support post  740  which is telescopically engaged in an open upper end of tube  734 . Seat support post has a series of openings for releasable engagement with a pull pin to adjust the seat pad height based on user size and preference. Arm support pads  744  are mounted at the upper end of forward tube  735  via mounting brackets  745 . Adjustment of the seat height accommodates users of different heights by varying the distance between the seat and the arm support pads. A pivot housing  747  extends upwardly from the upper end of the forward tube between the arm support pads. A foot support bar is transversely mounted at the lower end of tube  735  and a foot support  748  is mounted at each end of the support bar for engagement by a user&#39;s feet. Cross support  736  is pivotally attached to pivot mount  715  for rotation about user support pivot axis  750 . 
     Cable and pulley linkage  724  includes a pulley  752  mounted on base strut  725  and a pulley  754  mounted on the underside of user support cross bar  736  approximate its forward end. Cable  755  extends from an anchor  756  on base strut  725 , around pulley  754 , and then around pulley  752 . Cable  755  is then linked to the weight stack through the guide tube  728  in any suitable manner, including additional cables and pulleys. 
     Exercise arm assembly  716  comprises a main arm  758  having a pivot mount at one end pivotally connected between pivot brackets of the pivot housing  747  at the top of user support forward of upright tube  735  for rotation about first exercise arm pivot axis  762 , and a generally U-shaped handle arm member  764  having a central region pivotally attached to a pivot mount  765  (see  FIG. 16 ) at the forward end of main arm  758  for rotation about handle arm pivot axis  767 . Each section or arm of the U-shaped handle arm member  764  has an angled step  771  that places the outer ends of the handle arm member at a wider spacing than the inner, web connecting portion. This design allows multiple gripping positions for the user&#39;s hands. The pivotal connection between the handle arm member and the main exercise arm enables the user engaging handles to self-align to the user during the exercise and automatically adjust to the user&#39;s arm length. A stand-off tube (not visible in the drawings) extends from the main arm pivot mount inside the pivot housing  747  at the top of user support. 
     Connecting link  718  comprises a link arm or bar  766  which is pivotally attached at one end to a link connecting pivot mount  768  at the upper end of main frame forward upright  730  for rotation about first pivot axis  770  (see  FIG. 22 ). Link arm  766  is pivotally attached at its second end to a link connecting pivot mount  772  at the end of the stand-off tube of main arm  758  within the housing  747  for rotation about a second pivot axis (not visible in the drawings). The first pivot axis  770  of the connecting link is positioned above and forward of the user support pivot axis  750 , as best seen in  FIG. 22 . A bumper plate  774  with a rubber bumper is mounted on connecting link arm  766  approximate the first pivot point  770 , as illustrated in  FIG. 22 . Exercise arm  758  rests on bumper plate  774  in the rest or exercise start position. 
     In this embodiment, the user support is pivotally mounted to the main frame via the user support pivot mount  715 . The exercise arm is pivotally connected to the pivot housing  747  located between the user support arm pads. The connecting link pivotally joins the main frame with the exercise arm via the link connecting pivot mount  768  at the upper end of main frame upright  730  and the link connecting pivot mount at the end of the main arm stand-off within pivot housing  747 . 
       FIG. 21  illustrates the start position for a biceps curl exercise, while  FIG. 22  illustrates the finish position.  FIGS. 23 and 24  illustrate the same start and finish position with a user  700  seated on the machine and performing a biceps curl exercise. To perform the exercise, the user sits on the seat  738 , which rests at a slight forward inclination, places their feet on the foot rests  748  and rests their upper arms on the angled arm support pads  744 . The user aligns the pivot of their elbows as closely as possible with the pivot axis  762  at the exercise arm pivotal connection to the user support. Elbow groove  775  between the arm support pads  744  helps align the user. The user then grabs the user engaging handle  764  and starts the exercise movement by pulling the handle upward, towards their head. 
     This movement causes the exercise arm  716  to pivot about axis  762  relative to the user support, which rotates the stand-off secured to the main arm pivot mount  759  downward. As the stand-off rotates downward, it causes the connecting link  766  to rotate as it pivots about its connections to both the exercise arm and the main frame. This in turn forces the user support frame  714  to rotate, tilting it rearward about the user support pivot axis  750  at the user support&#39;s pivotal connection to the main frame. This pivot is designed to reorient the user&#39;s position from a forward lean to a rearward lean, duplicating the rearward arching motion of a “cheat” curl. This movement is done without changing the position of the user on the user support. Throughout the entire “cheat” movement, the user is in a stabilized position with their feet and upper torso supported. This stabilized position provides a strict exercise movement by preventing the involvement of other muscle groups and focusing effort just on the biceps. 
       FIGS. 23 and 24  show a user  700  on the machine in the start and finish positions respectively, with the vertical line  776  representing the gravitational centerline of the pivotal movement. The biceps curl exercise station places a portion of the user and user support frame on each side of the pivot&#39;s gravitational centerline in both the starting and finishing positions. By linking movement of the user support to movement of the exercise arm and positioning the user support pivot so that the combined weight of the user support frame and user is distributed on both sides of the pivot&#39;s gravitational centerline, the user support frame provides a counter-balancing effect on the exercise arm as it moves and its weight is re-distributed. 
     In the starting position, more of the combined weight of the user and user support frame is distributed towards the front side of the pivot. As the exercise arm is moved, more of this combined weight passes through the gravitational centerline until a more even distribution of weight is achieved. This re-distribution is gradual and continuous throughout the exercise motion and is not noticed by the user. By starting with a portion of the combined weight on the rearward or non-load side of the gravitational centerline, the initial lifting resistance is reduced. Re-distributing more of the combined weight to the non-load side at the end of the exercise increases the counter-balancing effect, lightening the resistive load slightly, which allows the user to come to full flexion and properly complete the exercise movement. This slight counter-balancing move mimics the momentum used on a free weight “cheat” curl to raise the weight to the top of its arc and finish the exercise. 
     The two exercise stations  602 ,  604  in the multi-station machine  600  of  FIGS. 16 to 23  are linked to separate weight stacks and can be used completely independently from one another. Different types of exercise resistance may replace the weight stacks in alternative embodiments, and the isolation stations may be used in other multi-station machines such as those of  FIGS. 1 to 15 , together or in combination with other types of exercise stations including rocking seat exercise stations for performing compound movement exercises, as well as stationary seat exercise stations. The biceps curl and leg extension stations may be replaced by other isolation exercise stations, such as triceps extension, leg curl, or the like. 
     In each of the above embodiments, one or more stations of a multi-station exercise machine has a user support which is pivotally mounted for pivotal movement relative to a main frame, and a connecting linkage which translates movement of an exercise arm or user engagement device into movement of the user support. The stations with moving user supports may be designed for performing compound or isolation exercises. 
     The stations of the multi-station exercise machines of the above embodiments which have a pivoting or moving user support all have a vertical gravitational center line extending through the pivot axis (where there is a single user support pivot) or theoretical pivot axis (where there is a multiple pivot assembly for the user support). The gravitational centerline of the user support&#39;s pivotal movement is positioned so that the combined weight of the user support and user is distributed on both sides of the gravitational centerline in at least one of the exercise start and end positions. Because of this arrangement, the user support provides a counter-balancing effect on the exercise arm as it moves and its weight is re-distributed. This balanced weight distribution positions a portion of the user and user support on each side of the gravitational centerline in either the start or end position, or both the start and end position. As the exercise arm is moved, a portion of this combined weight passes through the gravitational centerline redistributing the weight. This re-distribution is gradual and continuous throughout the exercise motion and is not noticed by the user. 
     In each station having a pivoting user support, the user support has a primary user support portion which supports the majority of the user&#39;s weight in at least one of the start and end positions of the exercise, as well as at least one additional or secondary user support portion which stays in the same position relative to the primary user support portion throughout the exercise, and supports a spaced portion of the user&#39;s body. An additional user support which supports another part of the user&#39;s body may also be provided. The multiple user supports provide secure and safe positioning, placing the user in the proper exercise alignment from start to finish, without any adjustment required by the user. The primary and secondary supports may be a seat pad and back pad, a seat pad and chest pad, a seat pad and thigh hold down pad, a seat pad and foot support, a back pad and shoulder pads, or other combinations of supports. The primary and secondary support travel together in fixed alignment to keep the user in the same position throughout the exercise motion so that the user does not have to worry about balancing on a moving platform or pad. In some embodiments, more than two user support portions may be provided on the user support frame, and also travel together with the primary and secondary supports for increased stability. For example, in some embodiments a foot plate to provide a rest for the user&#39;s feet during travel of the user support may be provided in addition to a back pad, chest pad, or thigh hold down pad, or hand grips may be provided in addition to a back pad and shoulder pads. 
     In each station with a pivoting user support, the connecting linkage which translates the user engagement device movement into movement of the user support is associated with at least two of the user engagement device, user support, and main frame. In some embodiments, such as the rear deltoid station of  FIGS. 1 to 4 , the connecting linkage is associated with all three of the user engagement device, user support, and main frame. The connecting linkage may have multiple parts or comprise a single rigid link, articulated links, completely flexible links, a sliding wedge link or rolling carriage, and the like, and the connecting linkage may be made adjustable. 
     The user engagement device may have linked or separate exercise arms movable in straight, parallel paths, diverging paths, or converging paths during an exercise, or may be a pivotally mounted exercise arm. The exercise arm or arms may be movably mounted on the main frame, connecting linkage, or user support frame, and may be partially flexible or articulated to allow user-defined movement of the user engagement device, or may be rigid arms. In those stations where the exercise arm is engaged by the user&#39;s hands rather than their feet, the handles may be rigid or flexible, and the exercise arm may provide for two-dimensional or three-dimensional movement. 
     In the exercise stations of the above embodiments which have moving user supports, operation of the user engagement device causes a rocking movement of the user support. Due to the position of the user support pivot or the theoretical pivot, the movement of the user and user support has only a small effect on the exercise resistance felt by the user, and there is no high resistance to be overcome in starting the exercise, or large resistance drop-off. The rocking movement of the user support recruits core stabilizing muscles and also makes the exercise enjoyable to perform. Repetitious exercise movement can be tedious and boring. By adding motion to the user support, without any large increase or change in resistance felt during the exercise, performing the exercise is more enjoyable and the user&#39;s interest in their workout increases. This is a benefit both to the individual exerciser, who may be motivated to exercise more regularly, and the fitness facility, where retention of members is a primary objective. 
     It should be understood that all the different elements used in the various embodiments may be mixed and interchanged with one another, and different types and forms of components could be used without affecting the scope of the invention. Cables could be replaced with belts, ropes, chains, or the like, and pulleys could be replaced with sprockets. The seat and/or back pad could be fixed or made adjustable. Various different types of user engaging pads can be used. The exercise arm or user engagement device could be unidirectional or bi-directional, and may be in one piece (dependent) or two pieces for independent arm movement. The exercise arm may be mounted on the user support, main frame, or connecting linkage, and the exercise arm movement may be rotational, linear, converging, or diverging, and may be user-defined. 
     The user support and user engagement device could be designed to travel in the same or opposite directions. The user support pivot mount may have a single pivot or multiple pivots, and in the latter case the user support pivots about a theoretical pivot mount of the combined pivotal motion. Any of the various embodiments could have the resistance associated with any of the moving parts (user support, user engagement device, or connecting linkage). The exercise resistance may be a weight stack linked to part of the apparatus by a cable and pulley arrangement, or may be weight plates. Any other type of resistance known in the art may alternatively be used, such as hydraulic, pneumatic, electromagnetic, or elastic bands, in place of the weight stack or weight plates. 
     In each multi-station machine, the user support in each station is positioned relatively low to the ground in the start and end position, making the stations quicker, easier, and safer to enter and exit. The user does not have to climb up or down in order to get into, or out of, the exercise position. The low profile also makes the machines more economical to produce and less intimidating to the user. The user&#39;s position is continuously adjusted throughout the exercise. The combined exercise arm and user support movement produces an automatic and continuous self-aligning exercise motion. 
     The above description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles described herein can be applied to other embodiments without departing from the spirit or scope of the invention. Thus, it is to be understood that the description and drawings presented herein represent a presently preferred embodiment of the invention and are therefore representative of the subject matter which is broadly contemplated by the present invention. It is further understood that the scope of the present invention fully encompasses other embodiments that may become obvious to those skilled in the art and that the scope of the present invention is accordingly limited by nothing other than the appended claims.