Abstract:
An exercise device with a true pivot point includes a first and a second arm joined at a joint assembly. The first arm is fixed in relation to the joint assembly and is also stabilized at an end opposite the joint assembly. The second arm rotates in a first, or in a second direction, about an axis of rotation which is defined by the joint assembly. A resistance mechanism is contained in the joint assembly which includes a one-way clutch interconnected to the second arm to allow the second arm to rotate freely in a second direction. Rotation by the second arm in a first direction, however, engages the resistance mechanism to create a resistance to the first rotation.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention pertains generally to physical exercise devices. More specifically, the present invention pertains to portable exercise devices and methods for using these devices. The present invention is particularly, but not exclusively, useful as an adjustable exercise device which allows the individual user to selectively stabilize the device during an exercise routine.  
         BACKGROUND OF THE INVENTION  
         [0002]    As is well known, a wide variety of exercise equipment is commercially available for purchase and use by individuals for purposes of developing their overall strength and physical condition. Often this equipment is designed for specific purposes, such as for exercising targeted muscle groups. The more complex and comprehensive the exercises become, however, it often happens that the exercise equipment also becomes more complex, more bulky, and less mobile. Similarly, exercise equipment that is designed for multiple exercises and for exercising multiple muscles becomes more complex, bulky and less mobile.  
           [0003]    In general, exercise equipment can be categorized as being either stationary equipment or portable equipment. Typically, stationary equipment is found in gyms, athletic facilities, training centers, and to a lesser degree in homes, and involves floor-mounted frames that normally incorporate heavy weights or other force generating mechanisms. An important reason for using stationary exercise equipment is that such equipment adds an element of stability to an exercise routine and provides a means for reacting forces being applied by the user to the equipment. In many exercise routines, and particularly those that are designed for physical therapy purposes, this element of stability may be very desirable. For instance, whenever there is a targeted muscle group, it may be important to insure that the muscle group is properly exercised. This means the exercise routine should involve repetitively consistent muscle contractions against a resistance of predictable magnitude and direction. To achieve these objectives, it is necessary to somehow stabilize the equipment. This is easily done with stationary equipment. By definition, however, stationary equipment is not portable and requires a dedicated area for its location.  
           [0004]    The use of portable exercise equipment has several advantages. One such advantage is availability. The convenience of being able to carry the equipment from site to site can be of considerable value to a user. This value can be significantly increased if the equipment itself is relatively light-weight and easy to handle. Further, as implied above in the context of stationary equipment, the versatility of portable exercise equipment can be significantly increased if it is somehow capable of being stabilized so that it is possible to reliably and consistently perform the repetitions of an exercise routine and be used at physiologically significant load levels. It is a further advantage if the portable exercise equipment can be quickly, easily, and conveniently configured for use when initiating an exercise session, and for performing a variety of exercise routines.  
           [0005]    In light of the above, it is an object of the present invention to provide a portable exercise device which can be stabilized during an exercise routine. Another object of the present invention is to provide an exercise device which includes an adjustable mechanism that will reliably and repeatedly provide a desired resistance to the user during an exercise routine. Another object of the present invention is to provide an exercise device that can be easily and quickly configured by the user to perform a variety of exercises. Another object of the present invention is to provide an exercise device that can be used for exercising various muscles within the body of the user. Another object of the present invention is to provide an exercise device that does not interfere with or constrain normal joint biomechanics during the user&#39;s performance of exercise routines with the device. Another object of the present invention is to provide an exercise device for use by an individual which is compact, portable, and safe. Yet another object of the present invention is to provide an exercise device which is relatively simple to manufacture, is easy to use and is comparatively cost effective.  
           [0006]    Other objects, features and advantages of the present invention will become apparent from the following description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principle of the invention.  
         SUMMARY OF THE PREFERRED EMBODIMENTS  
         [0007]    A portable exercise device in accordance with the present invention includes a first arm, a second arm and a joint assembly that interconnects the first arm with the second arm. For reference purposes, the joint assembly defines an axis of rotation that is substantially perpendicular to both the first arm and the second arm. Within this assembly, the first arm can be considered as having a fixed relationship with respect to the axis. On the other hand, the second arm is able to rotate about the axis. More specifically, the second arm is able to rotate freely in one direction around the axis, while being restrained by a resistance during a rotation in the opposite direction.  
           [0008]    Included in the joint assembly is a one-way clutch that is fixed to a cone member. A shaft that is fixed to the second arm is positioned within the one-way clutch. Through the action of the one-way clutch, the cone member moves together with the second arm when the second arm is moved in one direction, but it does not move with the second arm when the second arm is moved in the opposite direction. Also included in the joint assembly, along with the cone member, are a cup member and a friction liner. More specifically, both the cone member and the cup member have tapered surfaces that conform to each other, and the friction liner is positioned between these surfaces at their interface. Further, the cup member is connected directly to the first arm. An alternate embodiment is envisioned for the present invention which will not employ the one-way clutch. In this embodiment the cone member will move with the second arm in both directions.  
           [0009]    In the operation of the portable exercise device, the first arm is preferably stabilized in some manner by the user. With the first arm stabilized, the second arm will rotate freely about the axis in the direction wherein the one-way clutch does not engage movement of the second arm. Specifically, the shaft rotates freely within the one-way clutch. On the other hand, when the second arm is moved in the opposite direction, i.e. the direction wherein the one-way clutch fixedly engages with the second arm by way of the shaft, the second arm will encounter resistance. Specifically, when the one-way clutch becomes engaged, the tapered surface of the cone member will move relative to the tapered surface of the cup member. This movement will involve the friction liner and will generate a force that resists the rotation and is substantially constant throughout the movement. It will be appreciated by the skilled artisan that whenever there is no relative movement between the arms, i.e. when the second arm is stationary relative to the first arm, there is zero stored energy in the exercise device.  
           [0010]    Several alternate embodiments are envisioned for the present invention which will respectively use different mechanisms for generating a one-way or two-way resistance to the relative movement between the second arm and the first arm. Specifically, a spring or an elastomeric material can be positioned in the joint assembly and oriented to resist any relative movement of the second arm in a predetermined direction of rotation. Further, pneumatic, hydraulic, viscous shear, magnetic or electromagnetic systems can be used for this purpose.  
           [0011]    In the preferred embodiment of the present invention, control over the amount of the resistance there is to a rotation of the second arm, relative to the first arm, is accomplished at the joint assembly. Specifically, for this purpose the joint assembly includes a knob which is mounted on the cup member. This knob has a threaded connection with a plunger so that rotations of the knob will cause a translational movement of the plunger. The plunger, in turn, is in contact with a spring which is compressed or allowed to elongate with rotations of the knob, and this spring interacts with the cone member. Thus, in combination, a rotation of the knob activates the spring to urge the tapered surface of the cone member against the friction liner on the tapered surface of the cup member. Accordingly, depending on the direction the knob is rotated, the resistance to rotation between the cup member and cone member can be increased or decreased. There may also be a spring-loaded detent that is mounted on the cup member so that when the knob is turned, the detent is urged against detent notches in the knob to provide an aural signal in response to the rotation of the knob.  
           [0012]    It is an important aspect of the present invention that the device can be stabilized as the second arm of the device is rotated against the resistance created by the resistance mechanism. To do this, the first arm can include a stabilizing mechanism that is located at the end of the first arm opposite the joint assembly. Preferably, this stabilizing mechanism is a foot pedal. Alternatively, however, the stabilizing mechanism may be a friction surface, a mounting bracket, a handle, or some other suitable stabilizing element.  
           [0013]    The second arm can include an input mechanism that is located at the end of the second arm opposite the joint assembly. Preferably, this mechanism is a handle that can be placed in a variety of positions.  
           [0014]    The present invention also envisions that a position sensor can be mounted on the device to monitor repetitions in an exercise routine. If used, the sensor can generate signals which represent changes in the relative positions of the arms of the device. These changes can then be timed and used to count repetitions or cycle duration that may be useful for monitoring the exercise routine. A computer or microprocessor interface can also be established to monitor the signals that are generated by the position sensor.  
           [0015]    It is further envisioned that a load or strain sensor can be mounted on the device to monitor the load applied by the user of the device to rotate the second arm against the resistance created by the resistance mechanism. If used, the sensor can generate a signal that is proportional to the magnitude of force applied by the user of the device. This signal can be used to calculate the peak, average, and minimum load applied by the user in each exercise cycle. The signal can also be monitored and timed to count repetitions or cycle duration. A computer or microprocessor interface can also be established to monitor the signals that are generated by the load or strain sensor, and to calculate and display other useful exercise information.  
           [0016]    During an exercise routine, the exercise device of the present invention can be used by an individual to perform, for example, biceps exercises. To do this, the individual sets the resistance according to his or her strength and exercise goals. Once the resistance is set, the individual user then stabilizes the first arm of the device by stepping on the foot pedal. While positioning the elbow in close alignment with the axis of rotation of the joint assembly, the individual can then grasp the handle that is attached to the extended end of the second arm. The second arm can then be rotated in a clockwise or a counterclockwise rotation about the joint assembly. In one scenario, a clockwise rotation produces resistance as the targeted muscles contract. During a counterclockwise rotation, however, the resistance is released, and the second arm can be returned to its initial position. For subsequent exercise routines, the resistance can be increased as the muscles become stronger. Further, the device can be easily and quickly reconfigured to change the direction of resistance or to change to other configurations so that the user can alter body positions or alter the relationship of the device relative to the user for other exercise routines and for exercising other muscles. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0017]    The novel features of this invention, as well as the invention itself, both as to its structure and its operation, will be best understood from the accompanying drawings, taken in conjunction with the accompanying description, in which similar reference characters refer to similar parts, and in which:  
         [0018]    [0018]FIG. 1 is a perspective view of the exercise device of the present invention shown with peripheral computer equipment;  
         [0019]    [0019]FIG. 2 is a cross sectional view of the joint assembly of the exercise device of the present invention as would be seen along a line  2 - 2  in FIG. 1 when the device is straightened;  
         [0020]    [0020]FIG. 3 is a plan view of the interconnection between the plunger and bushing of the joint assembly as seen looking along the axis of rotation shown in FIG. 2;  
         [0021]    [0021]FIG. 4 is an exploded view of a handle assembly;  
         [0022]    [0022]FIG. 5A is a side elevation view of a user with the exercise device positioned with the joint assembly at the elbow (joint being exercised) and with the user&#39;s arm extended;  
         [0023]    [0023]FIG. 5B is a side elevation view of a user with the exercise device positioned with the joint assembly at the elbow (joint being exercised) and with the user&#39;s arm flexed;  
         [0024]    [0024]FIG. 6A is a side elevation view of a user with the exercise device positioned with the joint assembly remotely positioned and with the user&#39;s arm elevated;  
         [0025]    [0025]FIG. 6B is a side elevation view of a user with the exercise device positioned with the joint assembly remotely positioned and with the user&#39;s arm lowered;  
         [0026]    [0026]FIG. 7A is a side view representation of a user operating the exercise device of the present invention with rotation in one direction;  
         [0027]    [0027]FIG. 7B is a side view representation of the user operating the exercise device with a rotation in an opposite direction; and  
         [0028]    [0028]FIG. 8 is a perspective view of an alternate embodiment of the exercise device of the present invention. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0029]    An exercise device in accordance with the present invention is shown in FIG. 1 and is generally designated  10 . As shown, the device  10  includes a first arm  12 , which has a first end  14  and a second end  16 . The device  10  also has a second arm  18  which has a first end  20  and a second end  22 . As shown in FIG. 1, the second arm  18  has a handle  24  that is attached at its second end  22 . It is to be appreciated, however, that the handle  24  can be pivoted about the end  22  through an arc of approximately one hundred and eighty degrees so that the handle  24  extends from the arm  18  in a direction opposite to that shown in FIG. 1. Additionally, both the first arm  12  and the second arm  18  have respective locking rings  26   a  and  26   b  that can be manipulated in a manner well known in the art to telescopically adjust the respective lengths of the arms  12  and  18 .  
         [0030]    [0030]FIG. 1 also shows that the device  10  includes a joint assembly  28  which, for reference purposes, defines an axis of rotation  30 . In their relationship to this axis of rotation  30 , the first arm  12  is attached to the joint assembly  28  to establish a fixed relationship between the first arm  12  and the axis of rotation  30 . On the other hand, the second arm  18  is pivotally attached to the joint assembly  28  for a reciprocal rotation of the second arm  18  about the axis of rotation  30 . More specifically, this rotation of the second arm  18  about the axis of rotation  30  can be in either a clockwise direction  32  or in a counterclockwise direction  34 . It is to be appreciated that the second arm  18  as shown in FIG. 1 can be rotated to other positions about the axis of rotation  30  to establish alternate exercise configurations of the device  10 .  
         [0031]    For a preferred embodiment of the device  10 , at least one foot pedal  36  can be attached to the second end  16  of the first arm  12  such that the foot pedal  36  can rotate about axis  138  or an axis substantially parallel to and in close approximation to axis  138 . During use of device  10 , the foot pedal  36  is placed at a position located approximately ninety degrees relative to arm  12 . However, this angle can vary during use of device  10  to accommodate normal biomechanical motions. For storage, the foot pedal  36  can be rotated to a position next to arm  12 , substantially parallel to axis  136 . It is also envisioned that a position sensor  38  can be mounted on the device  10 , possibly at the joint assembly  28 , to generate signals  40  that are representative of the relative positions of said first arm  12  and said second arm  18  of the device  10 . Specifically, these signals  40  can be generated in a manner well known in the pertinent art and transmitted to a remote computer  42  or other electronic monitoring device for processing. More specifically, the signals  40  can be used to indicate the position of the first arm  12  relative to the second arm  18 , and to measure the time duration between changes in the relative positions of said first arm  12  and said second arm  18  of the device  10 . It is further envisioned that a load sensor  106 , such as a strain gauge, can be mounted on the device  10 , possibly near handle  24 , to generate signals  40  that are representative of the loads that are applied to the handle  24  of device  10 . These signals  40  also can be generated in a manner well known in the pertinent art and transmitted to a remote computer  42  or other electronic monitoring device for processing and displaying useful information regarding exercise sessions. Thus, exercise repetitions, the duration of each repetition, and the load applied by the user  90  (FIG. 5A) during each repetition in an exercise routine can be monitored. Furthermore, other exercise performance information and data can be determined from the signals  40 .  
         [0032]    Turning now to FIG. 2, the resistance mechanism that is incorporated into the joint assembly  28  of the device  10  is shown in detail. There it can be seen that the arm  18  is connected to an extension member  44  by means, such as the screw  46 , and that the extension member  44  is connected to a shaft  48  by means, such as the screw  50 . As shown, the shaft  48  is centered on the axis of rotation  30 . Further, the resistance mechanism includes a circular one-way clutch  52 , of a type well known in the pertinent art. The one-way clutch  52  may also have an integral bearing assembly. In a preferred embodiment, the one-way clutch is a Torrington Type DC Roller Clutch and Bearing Assembly, part number RCB-162117. Those of ordinary skill in the art will understand, however, that the one-way clutch  52  may comprise a variety of suitable devices. The one-way clutch  52  is also centered on the axis of rotation  30  and the shaft  48  is formed with a recess  54 .  
         [0033]    A cone member  56  is included in the joint assembly  28  and is positioned against the one-way clutch  52 . As shown in the preferred embodiment, this cone member  56  is formed with a tapered surface  58  that surrounds the axis of rotation  30  and is angled relative to the axis of rotation  30  at angle β. In a preferred embodiment, angle β is between ten and fifteen degrees. However, those of ordinary skill in the art will understand that there are many suitable values for angle β including ninety degrees, in which case tapered surface  58  will be substantially perpendicular to the axis of rotation  30 . Additionally, the cone member  56  includes a rim  60  that is oriented radially on the axis of rotation  30 . This rim  60  projects over the recess  54  of the shaft  48  substantially as shown. Also included in the joint assembly  28  is a cup member  62  which has a tapered surface  64 , and which is attached directly to the arm  12  by means such as the screw  66 . Importantly, the tapered surface  64  of the cup member  62  is dimensioned to mate with the tapered surface  58  of the cone member  56 . As intended for the device  10 , a friction liner  68  is positioned between the respective tapered surfaces  58  and  64  of the cone member  56  and the cup member  62 . Preferably, the friction liner  68  is fixed to either the cone member  56  or the cup member  62 . Also, the cup member  62  is formed with an annular groove  70  that is substantially centered on the axis of rotation  30 .  
         [0034]    Still referring to FIG. 2, it is seen that the joint assembly  28  includes a knob  72  that is connected to a threaded ring  74  by means such as the screws  76   a  and  76   b . Further, the ring  74  is threadably engaged with a plunger  78 . As shown, the plunger  78  is formed with a flange  80  that is inserted into the recess  54  of the shaft  48 . Additionally, a force transfer mechanism, such as a spring  82 , and a thrust bearing  110  are positioned in the recess  54  between the flange  80  of plunger  78  and the rim  60  of cone member  56 . The relative position of spring  82  and thrust bearing  110  is interchangeable. In a preferred embodiment, spring  82  is two Berg belleville washers, part number St- 7 , stacked in a parallel configuration, and thrust bearing  110  is a Torrington thrust needle roller and cage assembly, part number NTA-411 and two thrust washers, part number TRA-411. However, those of ordinary skill in the art will understand the spring  82  and the thrust bearing  110  may comprise a variety of suitable devices. A bushing  94  is mounted on the cup member  62  and is constrained from rotating about the axis of rotation  30  with respect to cup member  62  by means well known by those of ordinary skill in the art. Flange  100  of the knob  72  is positioned against the bushing  94 , and the knob  72  is constrained from translating along the axis of rotation  30  by radial surface  96  of bushing  94  and from moving in a radial direction relative to the axis of rotation  30  by the annular surface  98  of the bushing  94 .  
         [0035]    Turning to FIG. 3, it is seen that bushing  94  has a key  102  that protrudes into keyway  104  in plunger  78 . The interaction of the key  102  with the keyway  104  prevent the plunger  78  from rotating with respect to the bushing  94  and limits its motion to translation along the axis of rotation  30 .  
         [0036]    Referring again to FIG. 2, a plurality of spring-loaded detents  84 , of which the detents  84   a  and  84   b  are only exemplary, can be mounted on the cup member  62  to urge against the knob  72 . Further, the knob  72  can be formed with a plurality of recesses  86  so that as the knob  72  is rotated, the spring-loaded detents  84  will come into contact with the recesses  86  and thereby make an aural “clicking” sound. The contact of the detents  84  with the recesses  86  also provides incremental rotational setting of the knob  72  wherein there is a slight resistance to rotation of the knob  72  at each of these settings. As an additional matter, it is to be noted that a guide pin  88  is mounted on the extension member  44  and is inserted into the annular groove  70 . Thus, a rotation of the arm  18  around the axis of rotation  30  will be controlled by the interaction of the guide pin  88  in the groove  70 , preventing arm  18 , extension member  44  and shaft  48  from translating along the axis of rotation  30  relative to the cup member  62 . The guide pin  88  is held in position by set screw  112 .  
         [0037]    In the operation of the device  10 , a user  90  will first adjust the exercise resistance that is to be provided by the joint assembly  28 . Specifically, this is accomplished by rotating the knob  72 . With reference to FIG. 2, it will be appreciated by a skilled artisan that a rotation of the knob  72  causes the threaded ring  74  to interact with the plunger  78  in a way that will effect a translational movement of the plunger  78 . Accordingly, depending on the direction that knob  72  is rotated, the plunger  78  will either advance into the recess  54  or be withdrawn from the recess  54 . The consequence of this is that the force transfer mechanism (spring  82 ) will be respectively relaxed or compressed between the flange  80  of plunger  78  and the rim  60  of cone member  56 . In either case, the force that is generated by the spring  82  will act against the cone member  56 . Importantly, this force will be effectively transferred through the cone member  56  to establish a reactive force on the friction liner  68  at the interface between the tapered surface  58  of the cone member  56  and the tapered surface  64  of the cup member  62 . Furthermore, utilizing a force transfer mechanism (spring  82 ) allows the knob  72  to be rotated through larger angles in adjusting the exercise resistance from its lowest setting to its highest setting than would be possible if a force transfer mechanism was not employed.  
         [0038]    Through the action of the one-way clutch  52 , the arm  18  and its extension member  44  are able to freely rotate about the axis of rotation  30  when the arm  18  is rotated in a predetermined direction, e.g. the clockwise direction  32 . On the other hand, the one-way clutch  52  will fixedly engage the arm  18  with the cone member  56  when the arm  18  and its extension member  44  are rotated in the opposite direction, e.g. the counterclockwise direction  34 . As a consequence, when the arm  18  is fixedly engaged with the cone member  56  through the one-way clutch  52 , the rotation of the arm  18  will encounter the resistance that is established on the friction liner  68  between the cone member  56  and the cup member  62 . As indicated above, the amount of this resistance is established by rotating the knob  72 . Importantly, through the action of key  102  and thrust bearing  110 , plunger  78  and knob  72  are prevented from rotating when the action of the one-way clutch  52  causes cone  56  to rotate with respect to cup  62  as arm  18  is rotated. Further, the audible “clicks” that result when the detents  84   a,b  pass over recesses  86 , together with a visible gauge (not shown), can be used for determining preferred resistance levels.  
         [0039]    Turning now to FIG. 4, the handle assembly  108  of device  10  is shown in detail. There it can be seen that the handle  24  is connected to the outer hub  116  by means such as the shoulder screw  122 . As shown, the shoulder screw  122  is centered on the axis  134   b . The handle  24  is free to rotate about the axis  134   b , out of alignment with axis  134   c , approximately thirty degrees in a clockwise direction and a counterclockwise direction. A plurality of notches  132   a  and a plurality of notches  132   b  are formed on the inside circumference of outer hub  116 . The notches  132   a  are oriented at angle θ with respect to each other. Likewise, the notches  132   b  are oriented at angle θ with respect to each other. In a preferred embodiment, angle θ is equal to ten degrees. The notches  132   a  and  132   b  are oriented one hundred and eighty degrees with respect to each other about axis  134   a . Inner hub  114  has at least one key  130  formed on its outer circumference. The key  130  is dimensioned to mate with the notches  132   a  and the notches  132   b . The inner hub  114  fits within the outer hub  116  such that the key  130  fits securely within one of the notches  132   a  or one of the notches  132   b.    
         [0040]    The inner hub  114  is attached to the outer hub  116  by the shoulder screw  118  and the spring  120 . The shoulder screw  118  passes through the spring  120  and through the hole  124  in inner hub  114  and threads into the hole  126  in the outer hub  116 . As shown, the screw  118  and the spring  120  are centered on the axis  134   a . The spring  120  is constrained between the head of shoulder screw  118  and the inner surface  128  of the inner hub  114 , biasing inner hub  114  within outer hub  116 .  
         [0041]    To configure the handle assembly  108  for an exercise routine, the outer hub  116  is translated relative to the inner hub  114  along axis  134   a , compressing the spring  120  to a position where key  130  is clear of the notches  132   a  and the notches  132   b . In this position, the outer hub  116  can be rotated about axis  134   a  to a position where key  130  will align with any of the plurality of notches  132   a  or the plurality of notches  132   b . In a preferred embodiment, one of the notches  132   a  and one of the notches  132   b  are oriented on the inside circumference of the outer hub  116  such that the handle  24  will be aligned with axis  134   c  when the key  130  engages either of these notches. The inner hub  114  is attached to end  22  of arm  18  by means well known by those skilled in the art.  
         [0042]    Importantly, the ability of the handle  24  to freely rotate about axis  134   b , and to be selectively and fixedly positioned about axis  134   a , allows device  10  to be configured for the correct anatomical position and biomechanical motion of the hand, wrist and joints of the user  90 , both before and during an exercise routine cycle.  
         [0043]    [0043]FIGS. 5A and 5B show an exemplary use of the device  10  wherein the axis of rotation  30  is positioned close to the axis of rotation of the joint of the user  90  that is to be flexed and extended during an exercise routine. In this example, the elbow of the user  90 . The device  10  is stabilized by the user  90  by stepping on the foot pedal  36 . Rotation of the handle  24  by the user  90  in a counterclockwise direction  34  (FIG. 5A) will be met by a resistance force generated by the joint assembly  28  as the arm  18  is rotated about the axis of rotation  30 . Conversely, rotation of the handle  24  by the user  90  in a clockwise direction  32  (FIG. 5B) will meet no resistance from the joint assembly  28  as the arm  18  is rotated about the axis of rotation  30 . Further, the direction in which the resistance force acts can be reversed by first rotating the device  10  approximately one hundred and eighty degrees about axis  136  (FIG. 1) and then, if needed, rotating the handle  24  about the axis of rotation  30  or the axis  134   a  to place the handle  24  in the desired position for the exercise to be performed. The arms  12  and  18  can be lengthened or shortened to effect other exercises.  
         [0044]    [0044]FIGS. 6A and 6B show a use of the device  10  wherein the axis of rotation  30  on the device  10  is positioned at a distance from the axis of rotation of the joint of the user  90  that is to be flexed and extended during the exercise routine. In this example, the shoulder of the user  90 .  
         [0045]    [0045]FIGS. 7A and 7B show that as an alternative to stabilizing the device  10  by stepping on the foot pedal  36 , the user  90  can otherwise stabilize the device  10  by stepping on the arm  12 . Then, for example, movements of the user  90  from a leaning position (FIG. 7A) to a standing position (FIG. 7B) can be met by a resistance force. Specifically, this resistance force will be generated by the joint assembly  28  as the arm  18  is rotated about the axis of rotation  30  in the direction  34 . Conversely, movements of the user  90  from the standing position (FIG. 7B) to the leaning position (FIG. 7A) will meet no resistance from the joint assembly  28  as the arm  18  is rotated about the axis of rotation  30  in the direction  32 . Additionally, in an alternate embodiment of the device  10  shown in FIG. 8, the foot pedal  36  can be replaced by a handle  92 . Regardless which embodiment of the device  10  is contemplated, the position sensor  38  can be used to monitor or guide the exercise routine of the user  90 . For example, in addition to the signals  40  containing time information data, the signals  40  can also convey information about the relative positions of said first arm  12  and said second arm  18  of the device  10 . Thus, returning to FIGS. 5A and 5B, the signals  40  can include information on the angle α between the arm  12  and the arm  18  (FIG. 5A), and changes in this angle α to the angle α′ (FIG. 5B). Furthermore, the load sensor  106 , either in combination with the position sensor  38  or alone, can be used with any of the embodiments of the device  10  to monitor or guide the exercise routine of the user  90 . The signals  40  can also contain data regarding the magnitude of the force applied by the user  90  to the device  10  to overcome the resistance force generated by the joint assembly  28  as the arm  18  is rotated from a position at angle α, from arm  12  (FIG. 5A) to a position at angle α′ from arm  12  (FIG. 5B). Additionally, the signals  40  can contain data regarding the magnitude and relative direction of the force applied by the user  90  of the device  10  in returning the arm  18  from angle α′ to angle α. Such information and data, of course, can be useful for monitoring both the duration and the extent of exercise routines conducted with the device  10  as well as the magnitude of the loads applied to the device  10  by the user  90  during the exercise routines. This information and data can also be used by the computer  42  or other electronic monitoring devices to perform calculations and analysis of the exercise routines.  
         [0046]    While the particular exercise device with true pivot point as herein shown and disclosed in detail is fully capable of obtaining the objects and providing the advantages herein before stated, it is to be understood that it is merely illustrative of the presently preferred embodiments of the invention and that no limitations are intended to the details of construction or design herein shown other than as described in the appended claims.