Patent Publication Number: US-2022226690-A1

Title: Exercise Machine Reversible Resistance System

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     The present application is a continuation of U.S. application Ser. No. 17/139,209 filed on Dec. 31, 2020 which issues as U.S. Pat. No. 11,298,582 on Apr. 12, 2022 (Docket No. LAGR-229), which is a continuation of U.S. application Ser. No. 16/686,343 filed on Nov. 18, 2019 now issued as U.S. Pat. No. 10,881,896 (Docket No. LAGR-196), which is a continuation of U.S. application Ser. No. 15/871,950 filed on Jan. 15, 2018 now issued as U.S. Pat. No. 10,478,663 (Docket No. LAGR-152), which is a continuation of U.S. application Ser. No. 14/840,910 filed on Aug. 31, 2015 now issued as U.S. Pat. No. 9,868,019 (Docket No. LAGR-055), which claims priority to U.S. Provisional Application No. 62/043,503 filed Aug. 29, 2014 (Docket No. LAGR-038). Each of the aforementioned patent applications, and any applications related thereto, is herein incorporated by reference in their entirety. 
    
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not applicable to this application. 
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention relates generally to an exercise machine and more specifically it relates to an exercise machine reversible resistance system for reversing the directional force of resistance against an exercise implement before, during, or after the performance of a routine of one or more exercises. 
     Description of the Related Art 
     Any discussion of the related art throughout the specification should in no way be considered as an admission that such related art is widely known or forms part of common general knowledge in the field. 
     Exercise is human physical activity that enhances or maintains overall physical health of an exerciser. Exercise is performed to increase muscle strength, improve balance, improve cardiovascular efficiency, and to aid in weight loss. 
     Cardiovascular exercises are intended to improve circulatory and respiratory performance and health by raising the heart rate for an extended period of time, increasing oxygenation and calorie burn. Within the fitness industry, cardiovascular exercise as often referred to as “cardio”. Typical cardio exercise equipment found in gyms includes treadmills, stationary bikes, elliptical trainers, and stair climbers. Cardio exercises performed without the aid of specialized apparatuses include running and swimming. 
     Strength exercises are intended to increase the ability for muscles to perform more work. The exercises are practiced consistently over weeks or months. Strength exercises are typically performed in short but high intensity muscle bursts, rather than the long duration of cardio exercises. Strength training is intended to break down the muscles targeted by the exercise. The subsequent repair of muscle tissue after training is achieved by increased localized blood circulation that delivers nutrients and oxygen, both of which promote repair and growth of the muscle beyond its size and strength prior to exercise. 
     Strength exercise machines are apparatuses or devices providing for fixed or adjustable amounts of resistance, and which are used during physical activity to enhance the strength or conditioning effects of the performed exercises. 
     Myriad apparatuses have been made available by many manufacturers, each apparatus intended to work one targeted muscle or group of muscles. For instance, a bicep curl machine is intended to exercise only the bicep muscles, while a chest press machine is intended to primarily exercise the chest muscles, but to a lesser degree, shoulder and triceps muscles. 
     Strength exercise apparatuses may incorporate as the resistance source free weights, for example, barbells, dumbbells or stacked weights, resistance springs or bands, or position the exerciser so as to use the exerciser&#39;s own body weight as the weight resistance source. 
     Contemporary methods of exercising against a workload are many, and well known to those skilled in the art. One method of creating a direct vertical workload is an exerciser&#39;s application of force to lift a dead weight from a resting position to a higher vertical position. Another method of creating a horizontal workload is to redirect a vertical workload along a horizontal vector using a pulley or mechanical linkage. Yet another method of creating a workload in any direction is to apply a force opposite the force axis of a variable resistance means, such as a spring or elastic resistance band. 
     Still another method of creating a workload is to require a continuous cycle of lifting one&#39;s own body weight. For instance, a person exercising on a motorized treadmill is required to increase or decrease the elevation through which they lift their body with each step, and/or to increase or decrease the speed or length of stride in order to maintain their relatively stationary position upon the moving treadmill belt. Increasing the pitch of the treadmill belt further causes the exerciser to increase their work by lifting their body weight higher with each step in order to maintain their position on a treadmill. 
     Those skilled in the art will recognize that most all exercise apparatuses provide for continuous or cyclical exercising in one primary direction. For instance, an bicep curl machine is operated by an exerciser repeatedly flexing their bicep to raise their lower arm against a prescribed weight, then by slowly releasing the bicep muscle flex, allows the re-extension of their lower arm to return the weight to the starting point, then repeat the cycle for a prescribed number of times. 
     On the other hand, a triceps apparatus works opposite to a bicep curl apparatus in that the primary work is performed by flexing the triceps to extend the forearm to substantially align with the upper arm while working against a weight or resistance. By slowly relaxing the triceps, the weight is returned to its starting point as the lower arm assumes a decreasing angle relative to the upper arm. 
     As can readily be understood in the foregoing descriptions, exercise machines are intended to deliver a workload in one direction only. The primary work cycle on a bicep machine is achieved when the hand working against the resistance approaches the shoulder, while the primary work cycle on a triceps machine is achieved when the hand working against the resistance moves away from the shoulder. Therefore, a bicep machine does not appreciably exercise triceps, and a triceps machine does not appreciably exercise the biceps. 
     Another form of exercise produces a mixed benefit of combining cardio and strength training. Known to those skilled in the art, circuit training is a form of exercise that requires the exerciser to continuously work against resistance for a prolonged period, as previously described in cardio exercises, yet also incorporates a routine of large number of exercises that are performed in a rapid sequence, without any appreciable rest between each exercise. 
     One variation of circuit training is sometimes referred to as interval training wherein the exerciser generally performs the same exercise for a period of specific duration, similar to cardio exercising, but varies the resistance level throughout the routine period to substantially increase the exerciser&#39;s workload for short duration, high intensity bursts, then decrease the workload during a moderate recovery period whereby the cardio exercise intensity is maintained until a subsequent burst. The exerciser repeats this high/low intensity cycle until the end of the training period. 
     A disadvantage of attempting to perform circuit or interval training on a variety of exercise apparatuses by immediately and without an appreciable rest period, moving from one apparatus for one exercise, to another apparatus for a subsequent exercise is that in a typical gym environment, there will be another exerciser already working out on the next apparatus in the sequence, forcing the circuit exerciser to wait until the apparatus is available. This breaks the intended benefits of the continuous cycle of circuit training. 
     Another disadvantage of performing circuit training using multiple apparatuses in sequence within a gym environment is that even if the next apparatus is vacant, the proper weight, resistance level, or direction of resistance must be re-set for each exerciser. In many instances, this is time consuming, confusing, and the proper weight setting cannot be readily determined. Again, the break in the circuit sequence reduces the intended advantages of the circuit training session. 
     A disadvantage of attempting to perform a variation of circuit training upon a single exercise apparatus is that an exerciser must stop the exercise routine, most often by having to dismount the apparatus in order to change the existing resistance settings to new settings or to reverse the direction of resistance. The exerciser then re-mounts the apparatus and re-establishes proper positioning before continuing a new exercise at the new resistance setting. However, after a short period of performing a first exercise, often merely a minute or two, the exerciser would have to again dismount and change the resistance settings or the direction of resistance for a second exercise—then repeat the entire process with many additional exercises included in the particular routine. It often takes more time to change the resistance settings than the period of time the exerciser will actually perform the new exercise at the new setting. 
     Still another disadvantage of all of the exercise machines and Pilates apparatuses just described is that the resistance is unidirectional. In other words, none of the machines provide for an exerciser to immediately change the direction of the resistance force. 
     As an example, the rotating belt of a motorized treadmill is intended to move such that an exerciser, facing the front of the machine, can walk or run at different speeds, on a flat, or “uphill”. Reversing the rotation of the rotating belt would require the exerciser to begin walking or running backwards, and possibly “downhill”. Not only would this be an unnatural exercise, reversing a treadmill belt during exercise would be dangerous, and would likely be the source of many injuries. 
     As another example, a pull down machine to exercise the latissimus dorsi muscles provides a seat upon which an exerciser sits, and an overhead bar attached to a cable. The cable is threaded through a pulley on the machine, and is attached to weights. When an exerciser pulls down the overhead bar to work the latissimus dorsi or back muscles, the downward direction of their pull is reversed through the pulley, and they are actually pulling the weights that are attached to the cable upward from the floor. On the other hand, there is no provision to allow the exerciser to switch resistance direction so they can push upward on the bar and lift the weights to exercise the shoulders as would be provided by a shoulder press machine. Pushing upward provides no work resistance. 
     Yet another exemplary embodiment of the present invention is an improved exercise apparatus with a force reversing system providing for a plurality of exercise resistance springs affixed to an apparatus structure, a means providing for an exerciser to input an exercising force in one moveable direction sufficient to overcome one or more of the resistance springs, and a system providing for an exerciser to immediately reverse the direction of motion against which a counteracting resistance force will be applied. For instance, an exerciser&#39;s upward force movement as required to work against the spring resistance can be reversed to a downward force required to work against the spring resistance. 
     Another object of the present invention is an improved Pilates apparatus comprising a substantially longitudinal frame, an idler pulley affixed at substantially one end of the apparatus, a driven pulley on a drive shaft affixed at substantially the opposed end of the apparatus, a drive belt affixed to at least the idler and driven pulleys, and therebetween, an exercise carriage slidable along the longitudinal axis of the apparatus, the carriage being optionally engageable along the length of either side of the drive belt, thereby allowing an exerciser to select which direction the slidable carriage and correspondingly, the rotational direction of the driven pulley will move responsive to an exercise force input exerted upon the slidable platform. The reverser as currently illustrated is ‘self energizing’. This means that the more force an exerciser applies to the platform, pull the harder it tries to engage. A beneficial side effect is that if the exerciser pushes the rollable platform in the wrong direction, it disengages, thus preventing the platform back driving the spring mechanism. 
     Those skilled in the art will immediately recognize the deficiencies just described, and will understand that a sufficiently large number of machines to allow exercising of each major muscle group housing many machines requires leasing a large and expansive area for a functional gym or Pilates studio. They will appreciate that one machine capable of providing resistance for a wide variety of exercises allows for more economically efficient operations. 
     Further, fitness experts and gym operations will appreciate the commercial advantages of a new and improved exercise apparatus that provides for immediate and precise changing of the resistance level without considerable interruption to a workout routine, and a system of immediately reversing the direction of resistance to increase the number of muscles and muscle groups that may be exercised without dismounting the apparatus, thereby obviating the need to make complicated changeovers to the apparatus, or to move to another machine to perform a different exercise. 
     Because of the inherent problems with the related art, there is a need for a new and improved exercise machine reversible resistance system for reversing the directional force of resistance against an exercise implement before, during, or after the performance of a routine of one or more exercises. 
     BRIEF SUMMARY OF THE INVENTION 
     Provided herein is an exercise machine reversible resistance system which includes an exercise machine which has a movable exercise implement. The exercise implement is adapted to move with a drive belt which is connected at one end to a drive pulley and at the other end to an idler pulley. The exercise implement includes a clutch which selectively engages with different positions on the inner surface of the drive belt to adjust a direction of resistance applied against movement of the exercise implement. The clutch is movable between three positions: a first position in which the clutch is disengaged and no resistance is applied against the exercise implement, a second position in which the clutch is engaged with a first portion of the drive belt and resistance is applied against movement of the exercise implement in a first direction, and a third position in which the clutch is engaged with a second portion of the drive belt and resistance is applied against movement of the exercise implement in a second direction. 
     There has thus been outlined, rather broadly, some of the features of the invention in order that the detailed description thereof may be better understood, and in order that the present contribution to the art may be better appreciated. There are additional features of the invention that will be described hereinafter and that will form the subject matter of the claims appended hereto. In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction or to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of the description and should not be regarded as limiting. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Various other objects, features and attendant advantages of the present invention will become fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the several views, and wherein: 
         FIG. 1  is an upper perspective view of an exemplary embodiment of the present invention. 
         FIG. 2  is a side sectional view of a horizontal embodiment of the present invention in a first configuration. 
         FIG. 3  is a side sectional view of a horizontal embodiment of the present invention in a second configuration. 
         FIG. 4  is a side sectional view of a vertical embodiment of the present invention in a first configuration. 
         FIG. 5  is a side sectional view of a vertical embodiment of the present invention in a second configuration. 
         FIG. 6  is an upper perspective view of an additional exemplary embodiment of the present invention in which the elongated member is a chain. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Various aspects of specific embodiments are disclosed in the following description and related drawings. Alternate embodiments may be devised without departing from the spirit or the scope of the present disclosure. Additionally, well-known elements of exemplary embodiments will not be described in detail or will be omitted so as not to obscure relevant details. Further, to facilitate an understanding of the description, a discussion of several terms used herein follows. 
     The word “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments. Likewise, the term “embodiments” is not exhaustive and does not require that all embodiments include the discussed feature, advantage or mode of operation. 
     Turning now descriptively to the drawings, in which similar reference characters denote similar elements throughout the several views,  FIGS. 1 through 5  illustrate an exercise machine reversible resistance system  10 , which comprises a frame  23  having a first end and a second end, an elongated member  31  movably positioned upon the frame  23 , a resistance device  52  connected to the elongated member  31 , an exercise implement  26  movably connected to the frame  23 , and a clutch  60  connected to the exercise implement  26 . The elongated member  31  has a first run  31   a  and a second run  31   b  between the first end and the second end of the frame as illustrated in  FIGS. 1 through 5 . When the first run  31   a  moves in a first direction the second run  31   b  moves in a second direction that is substantially opposite of the first direction and when the first run  31   a  moves in the second direction the second run  31   b  moves in the first direction. The resistance device  52  applies a resistance force to the elongated member  31  in the second direction relative to the first run  31   a  and applies the resistance force to the elongated member  31  in the first direction relative to the second run  31   b.    
     The clutch  60  is adapted to selectively engage the first run  31   a  or the second run  31   b  of the elongated member  31 . The exercise implement  26  receives the resistance force in the second direction when the clutch  60  is engaged to the first run  31   a  as shown in  FIGS. 1, 2 and 4  of the drawings. The exercise implement  26  receives the resistance force in the first direction when the clutch  60  is engaged to the second run  31   b  as shown in  FIGS. 3 and 5  of the drawings. The clutch  60  is preferably comprised of a linear clutch to move in a linear manner. 
     The first run  31   a  and the second run  31   b  are preferably substantially parallel with respect to one another as illustrated in  FIGS. 1 through 5 . The first run  31   a  and the second run  31   b  may be horizontally aligned ( FIGS. 1 through 3 ), vertically aligned ( FIGS. 4, 5 ) or aligned at an angle between horizontal and vertical. The first run  31   a  may be positioned above, below, to the left or to the right of the second run  31   b . The first run  31   a  is distally spaced apart from the second run  31   b.    
     The elongated member  31  is comprised of an endless loop structure that rotates around a first wheel  30  and a second wheel  35 . The first wheel  30  is rotatably connected to the frame  23  and the second wheel  35  is rotatably connected to the frame  23  distally spaced from the first wheel  30  as illustrated in  FIGS. 1 through 5  of the drawings. The elongated member  31  is movably positioned upon the first wheel  30  and the second wheel  35 , wherein the first run  31   a  and the second run  31   b  are positioned between the first wheel  30  and the second wheel  35 . The elongated member  31  preferably includes a plurality of teeth  32  that are selectively engageable by the clutch  60 . The plurality of teeth  32  preferably extend inwardly toward one another between the two opposing runs  31   a ,  31   b  as illustrated in  FIGS. 1 through 5  of the drawings. The elongated member  31  may be comprised of a belt, chain or other elongated structure. The elongated member  31  is preferably comprised of a non-stretchable material. 
     The resistance device  52  may be directly connected to the elongated member  31  or indirectly connected to the elongated member  31 . For example, the resistance device  52  may be connected to the first wheel  30  to apply the resistance force against rotation of the first wheel  30  in a first rotational direction. The resistance device  52  may be comprised of a bias member that is elongated and resilient (e.g. elastic member, spring). 
     The clutch  60  is comprised of an actuator  70  and an engagement portion  64  extending from the actuator  70 . The actuator  70  may be comprised of a manually operated actuator (e.g. a lever) or a powered actuator (e.g. electric motorized actuator). The engagement portion  64  has a retracted position for engaging the first run  31   a  as shown in  FIGS. 1, 2, 4  of the drawings. The engagement portion  64  of the clutch  60  also preferably has an extended position for engaging the second run  31   b  as shown in  FIGS. 3, 5  of the drawings. 
     The invention in one embodiment is comprised of a frame  23  to which are connected a first wheel  30  and a second wheel  35 . The first wheel  30  and second wheel  35  will generally be spaced-apart, though the distance by which they are separated will vary in different embodiments of the present invention. In the embodiment shown in the figures, the first wheel  30  is positioned at or near the first end  21  of the exercise machine  20  and the second wheel  35  is positioned at or near the second end  22  of the exercise machine  20 . 
     An elongated member  31  is shown as connecting the first wheel  30  with the second wheel  35  such that rotation of the first wheel  30  will similarly rotate the freely-rotatable second wheel  35 . The first wheel  30  includes a first run  31   a  and a second run  31   b . It is noted that the particular locations along the inner surface of the elongated member  31  which comprise the first run  31   a  and second run  31   b  will vary as the elongated member  31  traverses the path between the first wheel  30  and second wheel  35 . Thus, the same location on the inner surface of the elongated member  31  which comprises a first run  31   a  will comprise the second run  31   b  of the elongated member  31  at a different time depending on positioning of the elongated member  31  on the first wheel  30  and second wheel  35  at that particular time. 
     The elongated member  31  of the present invention may comprise various configurations, and should not be construed as limited by the exemplary figures. In a preferred embodiment as shown in the figures, the elongated member  31  comprises a belt having a plurality of teeth  32  extending along its inner surface. In other embodiments, the elongated member  31  could comprise a chain with a plurality of links, rather than teeth  32 . In other embodiments, the elongated member  31  could comprise a flat surface without any projections such as teeth  32  as discussed herein. 
     The exercise machine  20  includes an exercise implement  26  which is freely-movable in at least two directions, such as by being movably connected to a frame  23  or rails  27 . The exercise machine  20  may be free-standing, such as through use of support feet  24 , or may be connected to another structure, such as in a cantilevered configuration. 
     A bias member  52  is interconnected with the exercise implement  26  as discussed herein such that the bias member  52  will exert resistance against movement of the exercise implement  26  in multiple directions depending on positioning of a clutch  60 . The exercise implement  26  may comprise various structures, devices, and the like, and should not be construed as limited by the exemplary figures herein.  FIGS. 1-3  illustrate an embodiment in which the exercise implement  26  comprises a movable carriage.  FIGS. 4-5  illustrate an embodiment in which the exercise implement  26  comprises a handle  25 . Various other types of exercise implements  26  may be utilized. 
     The clutch  60  of the present invention extends from the exercise implement  26 ; with the clutch  60  being movably connected to the exercise implement  26  in some embodiments. The clutch  60  is adapted to selectively engage with the first run  31   a  of the elongated member  31  to apply resistance against movement of the exercise implement  26  in a first direction and to selectively engage with the second run  31   b  of the elongated member  31  to apply resistance against movement of the exercise implement  26  in a second direction. Thus, use of the clutch  60  is operable to change the direction of resistance being applied against movement or manipulation of the exercise implement  26 . 
     The clutch  60  may comprise various configurations and should not be construed as limited by the exemplary figures. In the exemplary embodiment shown in the figures, the clutch  60  comprises an extension portion  62  which is connected at a first end to the exercise implement  26  and at a second end to an engagement portion  64 . The extension portion  62  may extend vertically downward as shown in the figures, or may extend in different orientations. The engagement portion  64  is illustrated as extending diagonally with respect to the downwardly-extending extension portion  62 , with the first end  65  of the engagement portion  64  being adapted to engage with the first run  31   a  of the elongated member  31  and the second end  66  of the engagement portion  64  being adapted to engage with the second run  31   b  of the elongated member  31 . 
     The manner in which resistance from the bias member  52  is transferred to be applied against movement of the exercise implement  26  will vary in different embodiments. One such embodiment is illustrated in the figures; however, the present invention should not be construed as being limited in any respect by the exemplary embodiment. There are numerous manners in which the resistance force of the bias member  52  may be transferred to be applied against the exercise implement  26 . 
     As shown in  FIGS. 1-5 , one such embodiment comprises the use of gear reduction pulleys  40 ,  42 . In this exemplary embodiment, a first gear reduction pulley  40  shares the same drive shaft  33  as the first wheel  30  such that the first gear reduction pulley  40  and the drive shaft  33  are concentric. The first gear reduction pulley  40  will generally comprise a smaller diameter than the first wheel  30  as shown in the figures. 
     A second gear reduction pulley  42  is connected to the exercise machine  20 , such as its frame  23 , by a gear reduction shaft  44 . The first gear reduction pulley  40  is connected to the second gear reduction pulley  42  by a gear reduction belt  43  such that the first and second gear reduction pulleys  40 ,  42  rotate together. In the embodiment shown in the figures, the second gear reduction pulley  42  is larger in diameter than the first gear reduction pulley  40 . 
     A separate resistance pulley  56  is illustrated as sharing the same gear reduction shaft  44  as the second gear reduction pulley  42 , with the resistance pulley  56  being concentric with the second gear reduction pulley  42 . The resistance pulley  56  may comprise a smaller diameter than the first wheel  30  as shown in the figures. The resistance pulley  56  and second gear reduction pulley  42  may comprise substantially the same diameter as shown in the figures, or may comprise different diameters. 
     The resistance pulley  56  is interconnected with the bias member  52  of the present invention. In some embodiments, the bias member  52  may be directly connected to the resistance pulley  56 . In other embodiments, a separate bias connector  50  may be provided which connects between the bias member  52  and the resistance pulley  56 . As shown in the figures, one embodiment of the bias connector  50  is comprised of a cable, with the cable being connected at one end to the resistance pulley  56  and at the other end to the bias member  52 . The bias member  52  may comprise various structures known to exert resistance, such as a spring as shown in the figures. 
     To maintain tension on the drive belt  30 , a tensioner pulley  38  may be provided which exerts force against the drive belt  30  to maintain its tension as shown in the figures. The tensioner pulley  38  may be located anywhere along the length of the drive belt  30 , including embodiments which exert tension against the upper portion of the drive belt  30  and embodiments (such as shown in the figures) which exert tension against the lower portion of the drive belt  30 . The tensioner pulley  38  will preferably be mounted on its own tensioner shaft  39 ; with the tensioner shaft  39  being connected to the exercise machine  20 , such as to its frame  23 . 
     The exercise machine reversible resistance system  10  is adapted to transition between a push-force configuration shown in  FIGS. 2 and 4 , in which the exercise implement  26  is resisted as it is moved in a first direction FE 1 , and a pull-force configuration shown in  FIGS. 3 and 5 , in which the exercise implement  26  is resisted as it is moved in a second direction FE 2 . As illustrated throughout the figures, the first direction FE 1  is opposite with respect to the second direction FE 2 . 
       FIG. 1  is an exemplary upper perspective view of the present invention. While this figure illustrates the exercise machine  20  as comprising a Pilates machine configuration, various types of other exercise machines  20  may be utilized as discussed herein. An exercise implement  26  is provided as part of the exercise machine  20 , and may be connected to any portion of the exercise machine  20 . The positioning of the exercise implement  26  will vary depending on the type of exercise machine  20  being utilized. 
     Any type of exercise machine  20  which utilizes an exercise implement  26  and bias members  52 , such as rowing machines, weight lifting machines, universal exercise machines, press machines, squat machines, curl machines, triceps machines, dip machines, elliptical trainers, and the like. Thus, the present invention should not be construed as being limited to any particular type of exercise machine  20  or exercise implement  26 . By way of example,  FIGS. 1-3  illustrate the present invention being utilized in combination with a Pilates machine. As an additional example,  FIGS. 4-5  illustrate the present invention being utilized in combination with an exercise machine  20  adapted to function as either a curl machine or a triceps machine depending on its configuration. 
       FIG. 2  is an exemplary diagram showing a side view of an exercise machine reversible resistance system  10  which is in a push-force configuration. More specifically, in the push-force exercise configuration as shown in  FIG. 1 , an elongated member  31  is installed around a first wheel  30  and a second wheel  35 . The first wheel  30  is affixed to a rotatable drive shaft  33  and the second wheel  35  is affixed to a rotatable idler shaft  36 , with the drive shaft  33  and idler shaft  36  being secured to the exercise machine  20 , such as to its frame  23 . A tensioner pulley  38  is provided as a means to create a preferred tension on the elongated member  31 , with the tensioner pulley  38  being affixed to a rotatable tensioner shaft  39 . 
     As shown in  FIG. 2 , a clutch  60  in the “push” position affixed to the exercise implement  26  is selectively engageable with the elongated member  31  such that when an exerciser  12  applies an exercise force FE 1  in the direction shown, the exercise implement  26  moves along the length of the exercise machine  20 , and the elongated member  31  correspondingly moves in the same direction, for the same length of travel as the exercise implement  26 . 
     A first gear reduction pulley  40  is affixed to the same drive shaft  33  as the first wheel  30 , with the first gear reduction pulley  40  and the first wheel  30  being concentric. The first gear reduction pulley  40  is adapted such that the first gear reduction pulley  40  rotates in response to exercise forces exerted upon the elongated member  31 . Rotation of the first gear reduction pulley  40  rotates a second gear reduction pulley  42  which is separately connected to a gear reduction shaft  44 ; with the first gear reduction pulley  40  and the second gear reduction pulley  42  being interconnected by a gear reduction drive belt  43 , thereby reducing the angle of rotation of the a resistance pulley  56  connected to the same gear reduction shaft  44  relative to the first gear reduction pulley  40 . 
     As shown in the figures, the resistance pulley  56  is connected to the gear reduction shaft  44  such that the resistance pulley  56  and the second gear reduction pulley  42  are concentric. The resistance pulley  56  is preferably of a smaller diameter than the first wheel  30  and a larger diameter than the first gear reduction pulley  40  as shown in the figures. The bias member  52  is interconnected with the resistance pulley  56  such that resistance force is applied against rotation of the resistance pulley  56  in a first direction. The bias member  52  may be directly connected to the resistance pulley  56 , or may be connected to the resistance pulley  56  by a bias connector  50  such as a cable as shown in the figures. 
     It is preferable that the first end  53  of the bias members  52 , where affixed to a bias connector  50 , travel a distance shorter than the measurable travel of the exercise implement  26 . The second end  54  of the bias members  52  is attached to the frame  23 . More specifically, the use of the gear reduction pulleys  40 ,  42  just described limits the rotation of the resistance pulley  56  to one revolution relative to the total range of travel of the exercise implement  26 , thereby limiting the bias connector  50  or bias member  52  winding about the resistance pulley  56  to one wrap. It is well known to those skilled in the art that when a cable is wrapped multiple times around itself on a pulley, the effective diameter of the pulley increases, and the force necessary to rotate the pulley increases. In the exercise machine of the present invention, a constant and predictable linear force against a predetermined resistance force FR is preferred to the requirement of an increasing force to continue rotating the resistance pulley  56 . 
     As the second gear reduction pulley  42  is rotated in response to the input exercise force upon the exercise implement  26 , the resistance pulley  56  similarly rotates with the same gear reduction shaft  44  such that the bias connector  50  free length shortens, thereby overcoming a predetermined resistance force FR extending one or more of the bias members  52  provided as a means to resist the exercise input force FEL 
     Oftentimes, it is preferable that an exerciser  12  contracts muscles that pull loads or resistance, rather than contracting opposing muscles that push loads or resistances. In such situations, an exerciser would shift the clutch from a “push” position as shown in  FIGS. 2 and 4  to a “pull” position shown in  FIGS. 3 and 5 , thereby engaging teeth  32  on the elongated member  31  on the opposite side of the first wheel  30 . As can readily be seen in the pull-force exercise configuration shown in the figures, with the clutch  60  engaged in the pull position and disengaged in the push position, the exerciser  12  may immediately begin exerting an exercise force on the exercise implement  26  in the opposite direction FE 2 , thereby providing for the engagement and exercise of the pulling muscles by directing the force against a resistance force FR. 
     Those expert in exercise machines  20 , and more specifically Pilates apparatuses, will immediately appreciate the benefit of providing the previously unknown system and method of reversing the direction of force that an exercise exerts upon an exercise implement  26 , including the ability to change from a pulling exercise to pushing exercise with little or no interruption of the overall exercise routine, and the elimination of the traditional requirement for an exerciser  12  to completely rotate their position upon an exercise machine  20  so that they are facing in a second direction opposite of the first direction so that they can engage a different set of muscles. Further, they will appreciate that by providing for the reversal of force direction upon the exercise implement  26 , the pushing and pulling exercises may be applied to a set of handles  25  at a first end  21  of the exercise machine  20 , thereby eliminating the requirement for any handles  25  at the second end  22  of the exercise machine  20 . 
     The figures illustrate the elongated member  31  as comprising a belt having a plurality of teeth  32  on its inner circumference. One of ordinary skill in the art will appreciate that multiple other types of drive connectors  31  may be utilized with the present invention, such as chains and the like. It should be noted that the preferable use of teeth  32  on the elongated member  31  is not meant to be limiting, flat belts, V-belts, as well as chains delivering the functionality just described may be used without deviating from the novel functionality of the present invention. 
     Further, the preferred clutch  60  system just described provides for the engagement of gear features of the clutch  60 , such as either of the ends  65 ,  66  of the engaging portion  64  shown in the figures, with teeth  32  on the elongated member  31  is not meant to be limiting, and the alternative methods of engaging a clutch  60  with an elongated member  31  such as a belt may include friction clamps such as a V-grooved plate engageable with a V-belt. Therefore, many methods of engaging the inside surface of a drive connector are well known, and may be used to accomplish the intended result in the novel, and previously unavailable system and method of the present invention providing for reversibly directing an exerciser&#39;s exercise force against one or more springs that provide resistance force FR in only one direction FE 1  or FE 2 . 
     In use, the clutch  60  will generally start in a position in which it is not engaged with any portion of the elongated member  31 . In this position, the exercise implement  26  may freely traverse the exercise machine  20  without any resistance from the bias member  52 . The exerciser  12  may freely position the exercise implement  26  at the desired location to begin an exercise without any force of resistance being transferred from the bias member  52  while the clutch  60  is disengaged. 
     Once the exercise implement  26  is located at the desired starting position for exercises, the clutch  60  may be engaged such that the bias member  52  exerts resistance against the exercise implement  26  as it is moved in a first direction FE 1 . In this case, the clutch  60  may be pulled upwardly such that the first end  65  of the engagement portion  64  of the clutch  60  engages with the first run  31   a  of the elongated member  31  as shown in  FIG. 2 . One manner of such engagement is shown in the figures, in which the first end  65  of the engagement portion  64  engages with the teeth  32  on the first run  31   a  of the first wheel  30 . The exerciser  12  may then perform various exercises with the exercise implement  26  being biased against movement in the first direction FEL 
     Upon completion a first set of exercises, the exerciser  12  may desire to reverse the direction of resistance. Utilizing the present invention, the exerciser  12  may easily and efficiently reverse the direction of resistance against the exercise implement  26  using only the clutch. Without getting off the carriage  12  or manipulating any other structure, the exerciser  12  may simply force the clutch  60  downwardly such that the first end  65  of the engagement portion  64  disengages with the first run  31   a  of the elongated member  31 . With continued downward force, the second end  66  of the engagement portion  64  will engage with the second run  31   b  of the elongated member  31 . When so configured, the exercise implement  26  will be resisted against movement in the second direction FE 2 . The exerciser  12  may then continue with a different set of exercises which utilizes the opposite direction of resistance than the first set of exercises. 
     The exerciser  12  may repeat these steps repeatedly to perform different sets of exercises against different directions of resistance. The exerciser  12  may dismount the present invention at any time. It may be preferable to position the clutch  60  in its disengaged position (i.e. the engagement portion  64  does not engage with any portion of the elongated member  31 ) such that the exercise implement  26  is freely movable into any position by a future exerciser  12 . 
       FIGS. 4 and 5  are exemplary diagrams showing a side view of the present invention in a vertical orientation. More specifically, the embodiment of the exercise machine reversible resistance system  10  shown in  FIGS. 1-3  is shown rotated so that the longitudinal axis to which a linear exercise force is applied to an exercise implement  26  is tilted so that the exercise force axis is substantially vertical. Utilizing the same principles as previously described, the present invention provides for a plurality of exercises typically performed while the upper body is substantially vertical. 
     For instance, those skilled in the art will appreciate that exercise machines  20  referred to as bicep curl machines allow an exerciser  12  to approach the machine, with arms substantially straight and extended grasp a handle  25  serving as an exercise implement  26  with one or both hands, and contract the bicep muscle against a resistance force until the hand is proximal to its respective shoulder. Thereafter, the exerciser would reverse the action, slowly releasing the bicep contraction, thereby allowing the lower arm to extend back to substantially the starting position. 
     One advantage of the present invention is that the exercise machine  20  as previously described weighs less than a machine that uses stacked weights. For example, a plurality of bias members  52 , together with an indexable resistance level selector with  15  ten pound increments, would provide a maximum of 150 lbs or resistance force for exercising biceps. The gross weight of the apparatus that includes the transmission system and bias members  52  would be estimated to weigh 80 pounds, depending on materials construction. 
     On the other hand, traditional curl machines using similar materials as just described, and that provide 150 pounds maximum resistance force, would necessarily contain a stack of 15 ten pound iron or steel weights, thereby weighing at least 150 pounds. Therefore, the weight savings which correspond to reduced manufacturing and freight costs, and reduced labor costs for delivering and setting up a curl machine in a gym are all reduced; making the variable transmission system commercially advantageous. 
     Further, by integrating the reversing clutch  60  system as herein described, the curl machine embodiment of the present invention shown in  FIGS. 4-5  can be immediately reversed, thereby becoming a triceps machine wherein an exerciser  12  starts with bent arms, and after grasping the handle  25  which serve as exercise implements  26 , may then extend their arms while pushing the handles  25  with a downward force by flexing their triceps. It is well known that exercisers  12  are advised to exercise counteracting muscles during a workout. Therefore, triceps and biceps are counteracting muscles, and after completing exercises for one muscle group, the opposing muscle group should be exercised. 
     Traditional gym machines do not provide for the reversing of the direction of exercise force since they are single exercise/single purpose designed. The novel function of the present invention provides for one exercise machine  20  that may functionally replace at least two traditional exercise apparatuses. Therefore, the present invention is more commercially valuable when compared to traditional gym machines in that it provides for significant reduction in the acquisition of equipment needed for a full service gym, and since in many instances, one exercise machine  20  of the present invention can replace the functionality of two machines, allowing a gym to provide the same exercise capacity, but with a substantially reduced facility size. 
     Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a wide variety of alternate and/or equivalent implementations may be substituted for the specific embodiments shown and described without departing from the scope of the present disclosure. This application is intended to cover any adaptations or variations of the embodiments discussed herein. 
     Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although methods and materials similar to or equivalent to those described herein can be used in the practice or testing of the present invention, suitable methods and materials are described above. All publications, patent applications, patents, and other references mentioned herein are incorporated by reference in their entirety to the extent allowed by applicable law and regulations. The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof, and it is therefore desired that the present embodiment be considered in all respects as illustrative and not restrictive. Any headings utilized within the description are for convenience only and have no legal or limiting effect.