Abstract:
An exercise apparatus includes a U-bar the ends of which are pivotally coupled to two L-bars by rotatable hinge assemblies containing a torsion spring. The rotatable hinge assemblies have a torsion spring tension setting means configured to vary the tension of the torsion spring and to secure the torsion spring at two or more distinct tensions settings without disassembly of the apparatus thus providing two or more distinct levels of resistance to the relative rotation of each L-bar independently with respect to the U-bar. Additionally, in certain embodiments of the apparatus each hinge assembly has an operation setting means that functions to control the allowable independent rotation of each L-bar relative to the U-bar end sections.

Description:
RELATED APPLICATION DATA 
       [0001]    This application claims priority under 35 U.S.C. §119 to U.S. Provisional Application Ser. No. 61/495,822 filed Jun. 10, 2011; Taiwan Application No. 100212735 filed Jul. 12, 2011; and China Application No. 201120248131.3 filed Jul. 14, 2011; all of which are herein included by way of reference in their entirety. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to an exercise apparatus, and more particularly to an abdominal muscle exercise apparatus with adjustable resistance. 
       BACKGROUND 
       [0003]    Abdominal exercise devices are known in the art. For example, U.S. patent application publication 2007/0027008 to Levinson et al. describes an abdominal exercise device including an upper abdominal lever member a lower abdominal lever member connected by with spring-biased resistance hubs, wherein operation of the lever members when rotated about the resistance hubs provides a scissor-like movement of respective upper and lower lever members connected to the resistance hub. However, such devices are very limited in the variety of exercises it permits, since the lever members are singular members. Also, while Levinson does allude to interchangeable resistance hubs pairs of varying resistance or tension, the apparatus must be disassembled and reassembled to effect each change of hubs and does not allow for a facile change of resistance during an exercise routine. Additionally, in such an apparatus the components required to change tension can be easily lost or misplaced. 
         [0004]    In another example U.S. Pat. No. 6,080,090 to Taylor et al. describes a folding portable exercise apparatus having a single padded U-bar and a single padded lap bar, wherein two pairs of length-adjustable telescoping rods connect the bars and each pair of telescoping rods is joined by a coil spring. While U.S. Pat. No. 7,341,547 to Liao describes an exercise apparatus having a base, a head member, two first mounting members, and two handles. The base includes a main portion, and two arm portions extending from opposite ends of the main portion. Such apparatuses are very limited in that they each fail to provide a means for a user to conveniently vary resistance and each design permits only limited exercise options. 
         [0005]    Therefore, the abdominal fitness devices known in the art have the following drawbacks that and required improvements. 
         [0006]    Since the resistance of such devices is fixed or not easily adjustable without disassembly, a user cannot make appropriate rapid adjustments of resistance during a training routine or for different training regimes. Furthermore, the devices having a single thigh leaning bar are designed for a user to lift both legs simultaneously thereby limiting the variety of exercises that can be performed. 
         [0007]    Therefore, a need exists for an abdominal fitness apparatus that allows users to make rapid adjustments to enable a variety of training modes. A further need exists for a portable apparatus that provides easily adjustable resistance without disassembly, such that users may rapidly and easily vary resistance during a training regime. A still further need exists for an apparatus that permits exercising each leg individually as well each side of the abdominal area individually. 
         [0008]    The present invention address these as well as other needs. 
       SUMMARY OF THE INVENTION 
       [0009]    A typical exercise apparatus of the present invention comprises a U-bar having a first U-bar end section comprising a first U-bar hinge component having a first U-bar hinge component internal surface and a first U-bar hinge component external surface, a second U-bar end section comprising a second U-bar hinge component having a second U-bar hinge component internal surface and a second U-bar hinge component external surface, wherein each U-bar hinge component is configured to define a U-bar hinge component pivot pin hole extending there through, and a U-bar median section wherein the first U-bar end section, the second U-bar end section and the U-bar median section are essentially coplanar and wherein each U-bar end section is perpendicular to the U-bar median section. The apparatus further comprises two mirror-imaged L-bars each having an L-bar proximal section and an L-bar distal section, wherein the end of each L-bar proximal section comprises an L-bar hinge component having an L-bar hinge component internal surface and an L-bar hinge component external surface, wherein each L-bar hinge component internal surface is mated to one of the corresponding U-bar hinge component internal surfaces and wherein each L-bar hinge component is configured to define an L-bar hinge component pivot pin hole extending there through. A pivot pin extends through each of the U-bar pivot pin holes and each of the corresponding L-bar pivot pin holes to provide a first rotatable hinge assembly and a second rotatable hinge assembly such that each L-bar is independently rotatable with respect to the U-bar and wherein each L-bar proximal section rotates in a plane parallel to the plane of the first and second U-bar sections. Each rotatable hinge assembly further comprises a torsion spring and a torsion spring tension setting means configured to vary tension of the torsion spring and to secure the torsion spring at two or more distinct tensions settings without disassembly of the apparatus thus providing two or more distinct desired levels of resistance to the relative rotation of each L-bar independently with respect to the U-bar. Furthermore, such a tension setting means allows for the quick and easy variation the resistance to rotation of each L-bar according to the requirements of the user. 
         [0010]    In certain preferred embodiments each torsion spring comprises a torsion spring first hook-shaped end and a torsion spring second hook-shaped end, wherein approximately half of the body of the torsion spring comprising the first hook-shaped end is disposed within an L-bar hinge component torsion spring embedding groove that extends into the L-bar hinge component internal surface and which is circumferentially disposed about the pivot pin hole and wherein the torsion spring second hook-shaped end is embedded and retained in an L-bar hinge component torsion spring retainer notch that extends into the L-bar hinge component internal surface and which is contiguous with the L-bar hinge component torsion spring embedding groove. While the approximately half of the body of the torsion spring comprising the second hook-shaped end is disposed within a U-bar hinge component embedding groove circumferentially disposed about the pivot pin hole extending into the mating U-bar hinge component internal surface and extending towards the periphery of the U-bar hinge component, wherein the U-bar hinge component embedding grove is configured to defines a U-bar hinge component embedding groove rim overhanging the U-bar hinge component embedding groove around the entire circumference. The torsion spring second hook-shaped end is disposed through a torsion spring hook access notch that extends into the U-bar hinge component internal surface and which is contiguous with the U-bar hinge component embedding groove. In such embodiments the torsion spring tension setting means comprises a tension adjustment knob springedly coupled to, and rotatable about, the pivot pin distal end, wherein the tension adjustment knob comprises a tension adjustment knob pin disposed parallel to the axis of the pivot pin. The first and second U-bar hinge components are each configured to define two or more adjustment knob pin holes extending though the U-bar hinge components embedding grooves parallel to the longitudinal axis of, and arranged circumferentially about, the pivot pin and dimensioned to accept tension the adjustment knob pin to be extended there through; wherein such an arrangement enables rotation of the tension adjustment knob as well movement of the tension adjustment knob along the pivot pin longitudinal axis to enable insertion of the adjustment knob pin into a selected one of the two or more adjustment knob pin holes, so that the adjustment knob pin engages the torsion spring second hook-shaped end, thereby setting the level of resistance to the relative rotation of each L-bar independently with respect to the U-bar. 
         [0011]    In certain preferred embodiments each hinge assembly is provided with an operation setting means that functions to control the allowable independent rotation of each L-bar relative to the first and second U-bar sections. In certain preferred embodiments the operation setting means comprise an operation setting pin having a proximal end and a distal end and an operation setting pin knob attached to the operation setting pin proximal end, wherein the operation setting pin is disposed within an operation setting pin hole extending through each U-bar hinge component parallel to the longitudinal axis of the pivot pin, and wherein the internal surface of each mating L-bar hinge component is configured to define an operation setting pin hole and an arc shaped operation setting pin slot positioned circumferentially about the pivot pin hole and proximate to the operation setting second pin hole; wherein both the operation setting pin holes and the arc shaped operation setting pin slots are dimensioned to accommodate the distal end of the operation setting pin. In certain of such embodiments the degree of arc is about 90°. 
         [0012]    In certain other preferred embodiments each L-bar is also provided with a cylindrical roller circumferentially disposed about the L-bar distal section near the distal ends of the L-bar. Such a roller is freely rotatable about the L-bar distal section and functions to cushion the contact between the apparatus and the thighs or other body parts of the user. In certain preferred embodiments the rollers comprise a soft resilient material such as rubber, foam rubber, soft plastic, textile or other suitable material. 
         [0013]    In a typical application a user assumes a starting position by sitting in a chair or on a bench and leaning the chest against the median section of the U-bar while the thighs contact the cylindrical rollers of the L-bars. The user then applies downward pressure with the chest to overcome the resistance of the torsion spring and rotate the U-bar median section toward the thighs to exercise the hip flexors and the lower abdominal muscles. Alternatively, a user can assume the same a starting position and then lift the thigh to overcome the resistance of the torsion spring and rotate the U-bar median section towards the chest to perform the thigh muscle training. Such a thigh training exercise can be performed by moving each thigh alternately or in unison. Furthermore, a different resistance level can be set for each thigh. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
         [0014]      FIG. 1  is a perspective view of an embodiment of an exercise apparatus of the invention. 
           [0015]      FIG. 2  is a perspective view of the apparatus illustrated in  FIG. 1  shown in a different configuration. 
           [0016]      FIG. 3  is a partial exploded view of the apparatus illustrated in  FIGS. 1 and 2 . 
           [0017]      FIG. 4  is an orthogonal side view of the apparatus illustrated in  FIG. 1  shown in a storage configuration. 
           [0018]      FIG. 5  is a cross-sectional view of a portion of  FIG. 4 . 
           [0019]      FIG. 6  is a cross-sectional view of a portion of  FIG. 4 . 
           [0020]      FIG. 7  is cross-sectional view of a portion of the apparatus illustrated in  FIG. 1 . 
           [0021]      FIGS. 8A and 8B  are perspective views of the apparatus illustrated in  FIG. 1  being utilized for an abdominal muscle exercise. 
           [0022]      FIG. 9  is an orthogonal side view of an application of the apparatus illustrated in  FIG. 1 . 
           [0023]      FIG. 10  presents an orthogonal side view of an application of the apparatus illustrated in  FIG. 1 . 
           [0024]      FIG. 11  presents an orthogonal side view of an application of the apparatus illustrated in  FIG. 1 . 
           [0025]      FIG. 12  presents an orthogonal side view of an application of the apparatus illustrated in  FIG. 1 . 
           [0026]      FIG. 13  is an orthogonal side view of the apparatus illustrated in  FIG. 1  shown in a storage configuration. 
           [0027]      FIG. 14  is a perspective view of the apparatus illustrated in  FIG. 1  shown in a storage configuration. 
           [0028]      FIGS. 15A and 15B  are perspective views of the apparatus illustrated in  FIG. 1  being utilized for strengthening the muscles of the back as well as the abdomen. 
           [0029]      FIGS. 16A and 16B  are perspective views of the apparatus illustrated in  FIG. 1  being utilized for an exercise to strengthen the muscles of the legs. 
           [0030]      FIGS. 17A and 17B  are perspective views of the apparatus illustrated in  FIG. 1  being utilized for an exercise to strengthen the gluteal muscles. 
           [0031]      FIGS. 18A and 18B  are perspective views of the apparatus illustrated in  FIG. 1  being utilized for an exercise to strengthen the lateral abdominal muscles. 
       
    
    
     DESCRIPTION OF THE INVENTION 
       [0032]      FIGS. 1-3  depict an embodiment of an abdominal fitness apparatus  10  of the present invention.  FIGS. 1 and 2  illustrate an assembled view of the embodiment comprising a U-bar  20  having two U-bar end sections  21 A and  21 B and a U-bar median section  23 ; wherein the U-bar end sections  21 A and  21 B and the U-bar median section  23  are essentially coplanar; and wherein the U-bar end sections are each terminated with mirror-image U-bar rotatable hinge components  24 A and  24 B respectively. The abdominal fitness apparatus  10  further comprises a first L-bar  31 A having first L-bar distal section  32 A and a first L-bar proximal section  35 A, and a second L-bar  31 B having second L-bar distal section  32 B and a second L-bar proximal section  35 B. The first L-bar proximal section  35 A is terminated with first L-bar rotatable hinge component  37 A and the second L-bar proximal section  35 B is terminated with second L-bar rotatable hinge component  37 B; wherein the two U-bar rotatable hinge components  24 A and  24 B are configured to mate with the two L-bar rotatable hinge components  37 A and  37 B respectively. 
         [0033]      FIG. 2  depicts the apparatus  10  as depicted in  FIG. 1 ; wherein the second L-bar  31 B has been independently rotated such that L-bar distal section  32 B has been moved toward the U-bar  20 , while the first L-bar  31 A remains in the same position as depicted in  FIG. 1 . Also, in apparatus  10  the U-bar median section  23  is contoured to accommodate the chest of a person using the apparatus. Such a contoured configuration of U-bar median section  23  is an optional feature of the invention. 
         [0034]      FIG. 3  presents an exploded view of the U-bar hinge component  24 B and the L-bar hinge component  37 B illustrating internal details of the overall rotatable hinge mechanism, wherein the rotatable hinge components  24 B and  37 B are configured to rotate about a hollow pivot pin  70 . The mirror image rotatable hinge components  24 A and  37 A are also configured to rotate about another pivot point  70  (not shown). By this configuration the first L-bar  31 A and second L-bar  31 B can be independently rotated with respect to the U-bar  20 . 
         [0035]      FIG. 3  also illustrates the U-bar hinge component  24 B, having a U-bar hinge component internal surface  25 B, and L-bar hinge component  37 B, having a L-bar hinge component internal surface  38 B, each configured to define U-bar hinge component circular pivot pin hole  40  and L-bar hinge component circular pivot pin hole  60  respectively extending there through and sized to accommodate hollow tubular pivot pin  70  having a proximal end, a distal end, an exterior surface and a lumen, which is also known as an interior surface; wherein the pivot pin  70  comprises a hexagonal flange  71  at the proximal end and a screw thread  72  around the surface of the distal end; and wherein the screw thread  72  is mated to a pivot pin retainer nut  75 . This embodiment further comprises optional hinge component gaskets  73  and  74 . The rotatable hinge assembly further comprises a pivot pin internal rod  76  sized to extend through a pivot pin compression spring  77 , such that the internal rod  76  and pivot pin compression spring  77  in combination extend through the lumen of the pivot pin  70 . The rotatable hinge assembly further comprises a spring torque adjustment knob  80 , which is configured to define an torque adjustment knob opening  81  sized to accommodate the pivot pin retainer nut  75 ; and a threaded hole  83  mated to the threaded distal end  78  of pivot pin internal rod  76 . The torque adjustment knob  80  further comprises a torque adjustment knob pin  82  disposed adjacent to torque adjustment knob opening  81  and extending along an axis parallel to the axis of the pivot pin  70 . When the rotatable hinge assembly of abdominal fitness apparatus  10  is fully assembled, the arrangement of components enables movement of the pivot pin compression spring  77  along the longitudinal axis of pivot pin  70  by extending or depressing the adjustment knob  80 , such that when the adjustment knob  80  is extended, i.e. pulled away from the U-bar hinge component  24 B, the compression spring  77  is compressed and when the adjustment knob  80  is subsequently released the compression spring  77  returns to a relaxed state. 
         [0036]    Also depicted in  FIG. 3  is a torsion spring  90  having a torsion spring first hook-shaped end  91  and a torsion spring second hook-shaped end  92 . Such a torsion spring is also commonly referred to as a torque spring. Approximately half of the body of the torsion spring  90  is disposed within a U-bar hinge component embedding groove  93  circumferentially disposed about circular pivot pin hole  40  extending into the U-bar hinge component internal surface  25 B and thereafter extending towards the periphery of the U-bar hinge component  24 B. The torsion spring second hook-shaped end  92  is disposed through a torsion spring access notch  94  that extends into the U-bar hinge component internal surface  25 B and which is contiguous with the U-bar hinge component embedding groove  93 . The U-bar hinge component  24 B is further configured to define three torque adjusting knob pin holes  100  extending though the hinge component  24 B and parallel to the longitudinal axis of circular pivot pin hole  40 . The adjusting knob pin holes  100  are arranged circumferentially about the circular pivot pin hole  40  at desired intervals and are dimensioned to accept the torque adjustment knob pin  82  extending there through. The other approximately half of the body of the torsion spring  90  is disposed within a torsion spring embedding groove  95  that extends into the U-bar hinge component internal surface  38 B and which is circumferentially disposed about circular pivot pin hole  60 ; wherein the torsion spring first hook-shaped end  91  is embedded and retained in a torsion spring retainer notch  96  that extends into the L-bar hinge component internal surface  38 B and which is contiguous with the torsion spring embedding groove  95 . 
         [0037]    By this arrangement, when the rotatable hinge mechanism is assembled, the torque adjusting knob  80  can be fully depressed such that the torque adjusting knob pin  82  is inserted into and extends through a chosen one of the torque adjusting knob pin holes  100  such that the torsion spring second hook-shaped end  92  is engaged by the torque adjusting knob pin  82  to set a desired resistance level to the torsion spring  90 , wherein the torque adjusting knob  80  is retained in this position aided by the arrangement of the pivot pin compression spring  77  and the pivot pin internal rod  76 . When the aforementioned components as depicted in  FIGS. 1 ,  2  and  3  are fully assembled, and the torque adjusting knob  80  is positioned such that the adjusting knob pin  82  is fully seated within in a desired adjusting knob pin holes  100 , the torsion spring  90  provides a desired relative rotational resistance between the U-bar  20  and the L-bars  31 A and  31 B and such a configuration allows the resistance to rotation of the U-bar  20  relative to the L-bars  31 A and  31 B to be conveniently varied by a user without disassembly of the rotatable hinge mechanisms. Although the embodiment depicted in  FIGS. 1-14  depicts three of such torque adjusting knob pin holes, the number of such torque adjusting knob pin holes, and therefore the number of discreet resistance levels obtainable, is in no way limited by the embodiment depicted and other embodiments may contain any plurality of torque adjusting knob pin holes greater than one. 
         [0038]    Additionally, the U-bar rotatable hinge component  24 B is configured to define an operation setting pin first hole  105  extending through the hinge component  24 B and parallel to the longitudinal axis of circular pivot pin hole  40 . The operation setting pin first hole  105  is dimensioned to accommodate the shaft of the operation setting pin  112 , which has an externally threaded operation proximal end  113  having a thread mated to the an internal thread  111  in an operation setting knob  110 . The operation setting pin  112  is configured to define a setting pin collar  115  disposed near the distal end  114  and having a diameter greater than that of the distal end  114  and the proximately threaded shaft. 
         [0039]    The L-bar hinge component  37 B is further configured to define an operation setting second pin hole  120 , which is dimensioned to accommodate the distal end  114  of the operation setting pin  112 ; and an arc shaped operation setting pin slot  121  positioned circumferentially about the circular pivot pin hole  60  and proximate to the operation setting second pin hole  120 ; wherein the arc shaped operation setting pin slot  121  is dimensioned to accommodate the distal end  114  of the operation setting pin  112 . Also an operation setting pin collar  115  is disposed circumferentially about the operation setting pin  112  near the operation setting pin distal end  114 . An operation setting pin compression spring  116  is dimensioned to accommodate the threaded shaft of the operation setting pin  112  disposed there through, while having a diameter greater that of the operation setting pin first hole  105 . The compression spring  116  provides a force for pushing the distal end  114  of the operation-setting pin  112  into the operation-setting second pin hole  120  or the operation-setting pin slot  121 . By this arrangement, when the rotatable hinge mechanism is assembled, the operation-setting knob  110  can be retracted thereby disengaging the distal end  114  of the setting pin  112  from either the second setting pin hole  120  or the setting pin slot  121 ; and whereby the operation-setting knob  110  can be depressed to retain the distal end  114  of the setting pin  112  in either the second setting pin hole  120  or within the setting pin slot  121 . The arc shaped operation setting pin slot  121  in this depicted embodiment has an arc of approximately 90°, however in other embodiments the arc can range from about 45° to 305°, preferably from 45° to 180° and most preferably from about 75° to 105°. 
         [0040]    By use of the operation-setting knobs  110 , the U-bar  20  and the L-bars  31 A and  31 B can be set to an operation or idle mode. In an operation mode, as shown in FIG.  4 ,  FIG. 5  and  FIG. 13 , the U-bar  20  and the L-bar  31 B (for simplicity L-bar  31 A is not shown) apparatus  10  are in the storage position as illustrated in  FIG. 14 , wherein the U-bar end section  21 B and the L-bar proximal section  35 B are parallel or nearly parallel such that the roller  33 B is at least partly disposed beneath the U-bar median section  23 . Such a storage position is achieved and retained by pulling the operation setting knob  110  until the operation setting pin  114  is completely disengaged from the L-bar hinge rotatable component  37 B, rotating the L-bar relative to the U-bar until the U-bar end section  21 B and the L-bar proximal section  35 B are essentially parallel and the releasing the operation setting knob  110  such that the operation setting pin  114  is engaged by the setting pin hole  120 . 
         [0041]    When the two operation-setting knobs  110  are adjusted and pulled outward as shown in  FIG. 7 , the distal ends  114  of the operation setting pins  112  are withdrawn from the operation setting second pin hole  120 , wherein an L-bar rotatable hinge component  37 A or  37 B is rotated to effect insertion of the distal end  114  of an operation setting pin  112  into the operation setting pin slot  121  as depicted in  FIG. 9 ,  FIG. 10  and  FIG. 11 , wherein the U-bar  20  and L-bars  31 A and  31 B are angularly disposed in various configurations such that a user can operate the apparatus  10  to perform various exercises. 
         [0042]    With reference to  FIG. 3 , the torsion spring  90  has a hook-shaped end  91  secured into a torsion spring retainer notch  96  in a L-bar hinge component internal surface  38 A or  38 B and a hook-shaped end  92  disposed within torsion spring access notch  94  in U-bar hinge component internal surface  28 A or  28 B. Since the hook-shaped end  92  of a torsion spring  90  is movable, when the U-bar  20  and an L-bars  31 A or  31 B are moved with respect to each other for the use in the exercise, the hook-shaped end  92  will move and the adjusting knob pin  82  of the spring torque adjustment knob  80  will be fixed in a position (as shown in  FIG. 6 ) such that that the hook end  92  of the torsion spring  90  becomes fixed. Since the hook-shaped end  91  of the torsion spring  90  is fixed within a rotatable hinge component  37 A or  37 B of an L-bars  31 A or  31 B and the hook-shaped end  92  is fixed by the adjusting knob pin  82  within a rotatable hinge component  24 A or  24 B of the U-bar  20 , both of the U-bar  20  and an L-bar  31 A or  31 B can be moved with respect to each other by overcoming the resistance of the torsion spring  90 . In addition, the resistance imposed by torsion spring  90  can be easily adjusted by controlling the insertion of the adjusting knob pin  82  of the spring torque adjustment knob  80  into one of the various torque adjusting knob pin holes  100  as depicted in  FIG. 12 . 
         [0043]    When the abdominal fitness machine is not in use, the operation setting knob  110  can be pulled outward permitting the U-bar  20  and the L-bars  31 A or  31 B to be turned towards one another such that the operation setting second pin hole  120  is aligned precisely with distal end  114  of the operation setting pin  112 . When the operation-setting knob  110  is released, the distal end  114  of the operation-setting pin  112  is moved back by the force of the operation setting pin compression spring  116  and embedded into the operation setting second pin hole  120  as depicted in  FIGS. 13 and 14 . In such a configuration, the U-bar  20  and the L-bars  31 A or  31 B are secured to one another for convenient storage. 
         [0044]    Certain embodiments of the apparatus are configured such that the L-bar(s) must be disposed at or near (within about 10°) a storage position in order to change the tension setting. 
         [0045]    Below are descriptions of several exercises that can be executed by an individual utilizing an apparatus of the present invention. 
         [0046]      FIG. 8A  depicts a user utilizing apparatus  10  in a position to execute an abdominal muscle exercise wherein a user is seated with the rollers  33 A and  33 B resting on the thighs, wherein the U-bar median section  23  leans against the chest. To execute the exercise the legs remains in the position shown and the chest pushes the U-bar median section  23  downwardly towards the rollers  33 A and  33 B to overcome the resistance of the torsion spring as shown in  FIG. 8B , wherein the movement is repeated as desired to perform various abdominal fitness and abdomen reduction exercises routines. From this same starting position of  FIG. 8A , the user&#39;s can maintain the back erect such that the chest becomes a support surface for the U-bar median section  23  and wherein the user can lift the left and right legs alternately, or in unison, wherein the force provided by the user&#39;s thighs overcomes the resistance of the torque spring  90  to move an L-bar rollers  33 A and  33 B towards the U-bar median section  23  to effect a thigh strength training exercise. 
         [0047]      FIGS. 15A and 15B  depict a user utilizing apparatus  10  to execute an exercise for strengthening muscles of the back as well as the abdomen. The starting position for this exercise is depicted in  FIG. 15A  wherein each L-bar is set at an angle approximately 90° with respect to the U-bar and a user is seated such that the U-bar median section  23  is positioned against the back of the user and the L-bars are positioned to extend away from the user such that the rollers  33 A and  33 B rest upon the surface on which the user is seated. To execute the exercise the user leans back to push the U-bar median section  23  downwardly towards the rollers  33 A and  33 B as shown in  FIG. 15B  and then returns to the starting position. To facilitate this exercise the user holds the apparatus  10  in place with the hands while executing the exercise. 
         [0048]      FIGS. 16A and 16B  depict a user utilizing apparatus  10  to execute an exercise for strengthening muscles of the legs. The starting position for this exercise is depicted in  FIG. 16A  wherein each of the L-bars is set at an angle approximately 90° with respect to the U-bar and a user is lying on a flat surface with his or her lower back against the flat surface. The U-bar median section  23  is positioned against or near the user&#39;s buttocks and the L-bars are positioned to upward from the flat surface. By bending the knees the user positions his or her calves such they rest on the rollers  33 A and  33 B. To execute the exercise the user pulls his or her feet towards the buttocks wherein the backs of the calves to push the rollers  33 A and  33 B the downwardly towards the U-bar median section  23  as shown in  FIG. 16B . The user then returns to the starting position. To facilitate this exercise the user holds the apparatus  10  in place with the hands while executing the exercise. 
         [0049]      FIGS. 17A and 17B  depict a user utilizing apparatus  10  to execute an exercise for strengthening the gluteal muscles. The starting position for this exercise is depicted in  FIG. 17A  wherein each of the L-bars is set at an angle approximately 90° with respect to the U-bar and a user is lying on a flat surface with his or her lower back against the flat surface. The U-bar median section  23  is positioned against the flat surface near the user&#39;s buttocks a with the U-bar proximal sections extending upward towards the user&#39;s head at an angle of about 45°. By bending the knees the user positions the backs of the upper portions of his or her calves such they rest on the rollers  33 A and  33 B. To execute the exercise the user straightens his or her legs wherein the backs of the thighs push the rollers  33 A and  33 B the downwardly towards the U-bar median section  23  as shown in  FIG. 17B . The user then returns to the starting position. To facilitate this exercise the user holds the apparatus  10  in place with the hands while executing the exercise. This exercise can be executed with one leg at a time or with both legs in unison. 
         [0050]    The lateral abdominal muscles are the muscles used when a person rotates the upper body or leans side-to-side. Technically, the lateral abdominal muscles are more properly referred to as the internal oblique and external oblique muscles, which are often collectively referred to as “the obliques”. For the purposed of the present invention lateral abdominal muscles and obliques have the same meaning. 
         [0051]      FIGS. 18A and 18B  depict a user utilizing apparatus  10  to execute an exercise for strengthening the lateral abdominal muscles.  FIG. 18A  depicts a user utilizing apparatus  10  in a starting position to execute a lateral abdominal muscle exercise wherein a user is seated with the U-bar median section  23  resting against the tops of the user&#39;s thighs and wherein the roller  33 A is disposed against the user&#39;s chest while the roller  33 B is disposed against the median section  23 . To execute the exercise the user&#39;s legs remains in the stating position as shown, while the user rotates at the waist and the chest pushes the roller  33 A downwardly towards the median section  23  to overcome the resistance of the torsion spring as shown in  FIG. 18B , wherein the movement is repeated as desired. The lateral abdominal muscle exercise may also be performed with the opposite side of the body wherein a user is seated with the U-bar median section  23  resting against the tops of the user&#39;s thighs and wherein the roller  33 B is disposed against the user&#39;s chest while the roller  33 A is disposed against the median section  23 . To execute the exercise the user&#39;s legs remains in the stating position as shown, while the user rotates at the waist and the chest pushes the roller  33 B downwardly towards the median section  23  to overcome the resistance of the torsion spring. 
         [0052]    In summation of the description above, exercise apparatuses of the present invention provide various abdominal fitness and abdomen reduction and other exercises to strengthen other muscles of a user such as muscles of the legs and back. Such exercise apparatuses are compact and allow a user to easily adjust the resistance load foe each side of the apparatus independently for a desired training regime by use of a simple spring torque-adjusting knob. 
         [0053]    While the invention has been described with respect to specific embodiments, those skilled in the art with recognize that numerous modifications and variations could be made without departing from the scope and spirit of the invention herein described and set forth in the claims.