PATENT ABSTRACT
An apparatus that facilitates the stretching and exercising of the hamstring and back muscles is provided. The apparatus can be used for stretching to improve flexibility, to warm up muscles before physical activity, and/or for physical rehabilitation after injury. The apparatus includes a set of hand grips and a set of foot plates. A user grasps the hand grips and positions the arches of his or her feet above the foot plates. The apparatus includes a user actuated drive mechanism for moving a set of hand grips along the shaft toward the foot plates. The user maintains a grip of the hand grips as the hand grips move along the shaft toward the foot plates, thereby stretching the hamstring and back muscles of the user.

PATENT DESCRIPTION
RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. Provisional Patent Applications Ser. No. 61/168,537, filed Apr. 10, 2009, entitled “HAMSTRING STRETCHING DEVICE,” and U.S. Provisional Patent Application No. 61/222,850, filed Jul. 2, 2009, entitled “HAMSTRING STRETCHING DEVICE” which are hereby incorporated by reference in their entirety. 
     
    
     FIELD OF THE INVENTION 
       [0002]    This invention relates to exercise and medical devices for stretching muscles, and more particularly to a device for stretching the back and leg muscles. 
       BACKGROUND 
       [0003]    The hamstring muscle group comprises three muscles: the semitendinosus, the semimembranosus, and the biceps femoris. The hamstring muscle group acts upon both the hip and knee joints. The hamstrings play an important role in walking, running, jumping, and controlling some movement of the trunk of the body. 
         [0004]    Many people suffer from tightness of the hamstrings. Tightness of the hamstrings can be caused by genetic factors (some people are naturally born with shorter hamstring muscles), back problems can also cause the sciatic nerve to become compressed which can cause the hamstring muscles to tighten, and lack of stretching before physical activity can also cause tightness in the hamstring muscles. Furthermore, sedentary lifestyles and/or desk jobs that involve sitting for long periods of time can also contribute to tightness in the hamstring muscles. 
         [0005]    Tightness in the hamstring muscles can cause decreased physical performance and can make the muscles more susceptible to tearing during physical activities. Furthermore, the tightness in the hamstring muscles can also lead to postural problems and/or back problems by causing the hips and/or the pelvis to rotate to position that can compress nerves and/or put strain on other muscle groups. Pain in the back and knees are also a common result. 
         [0006]    Stretching of the back and hamstring muscles can increase flexibility and blood flow to these muscles groups and can help to alleviate pain and/or stiffness caused by tightening of the hamstring muscles. 
       SUMMARY 
       [0007]    An apparatus that facilitates the stretching and exercising of the hamstring and back muscles is provided. The apparatus described herein can be used for stretching to improve flexibility, to warm up muscles before physical activity, and/or for physical rehabilitation. The apparatus includes a set of hand grips and a set of foot plates. A user grasps the hand grips and positions the arches of his or her feet above the foot plates. The apparatus includes a user actuated drive mechanism for moving a set of hand grips along the shaft toward the foot plates. The user maintains a grip of the hand grips as the hand grips move along the shaft toward the foot plates, thereby stretching the hamstring and back muscles of the user. 
         [0008]    According to an embodiment, an exercise device for stretching the hamstring and muscles is provided. The device includes a support shaft. a set of foot plates disposed at one end of the support shaft, a set of hand grips slideably disposed on the support shaft and being moveable upward along the shaft away from the foot plates and moveable downward along the shaft toward the foot plates, and a user-actuated drive mechanism comprising a ratchet for moving the hand grips and ratchet downward along the support shaft toward the foot plates when the user-actuated drive mechanism is activated. 
         [0009]    According to another embodiment, an exercise device for stretching the hamstring and back muscles is provided. The device includes a support shaft, a set of foot plates disposed at one end of the support shaft, a set of hand grips slideably disposed on the support shaft and being moveable upward along the shaft away from the foot plates and moveable downward along the shaft toward the foot plates, and a user-actuated drive mechanism comprising a motor for moving the hand grips downward along the support shaft toward the foot plates when the user-actuated drive mechanism is activated. 
         [0010]    According to yet another embodiment, a method of stretching the hamstring and back muscles using an apparatus that includes a user actuated drive mechanism and a hand grip slideably disposed on a shaft, and a foot rest disposed at one end of the shaft, the user actuated drive mechanism being configured to move the hand grip along the shaft toward the foot rest when the drive mechanism is activated by the user. The method includes positioning the footplate of the device under the arches of the user&#39;s feet while maintaining the position of the legs relatively straight, grasping the hand grips of the apparatus, squeezing the hand grip of the apparatus to actuate the drive mechanism, causing the drive mechanism to move the hand grip along the shaft towards the foot plates, thereby stretching the back and hamstring muscles of the user. 
         [0011]    Other features and advantages of the present invention should be apparent from the following description which illustrates, by way of example, aspects of the invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0012]    The details of the present invention, both as to its structure and operation, may be gleaned in part by study of the accompanying drawings, in which like reference numerals refer to like parts, and in which: 
           [0013]      FIG. 1  illustrates an apparatus for stretching the hamstring and back muscles according to an embodiment; 
           [0014]      FIG. 2  illustrates a ratchet-like structure that can be used to move the grip along the shaft of the apparatus illustrated in  FIG. 1  according to an embodiment; 
           [0015]      FIG. 3  illustrates the grip and ratchet system of the apparatus illustrated in  FIG. 1  according to an embodiment; 
           [0016]      FIG. 4  illustrates the footplate and main plate of the apparatus illustrated in  FIG. 1  according to an embodiment; 
           [0017]      FIG. 5  illustrates the shaft of the apparatus illustrated in  FIG. 1  according to an embodiment; 
           [0018]      FIG. 6  illustrates the handle and top end cap of the apparatus illustrated in  FIG. 1  according to an embodiment; 
           [0019]      FIG. 7  is flow chart illustrating a method of stretching muscles using the apparatus illustrated in  FIGS. 1-6  according to an embodiment; 
           [0020]      FIG. 8  illustrates an alternative implementation of the apparatus illustrated in  FIG. 1  that includes a motor for moving the grip along the shaft of the apparatus according to an embodiment; 
           [0021]      FIG. 9  is a logical block diagram of a motor component that can be used with the apparatus illustrated in  FIG. 8  according to an embodiment; and 
           [0022]      FIG. 10  is a flow chart of a method of stretching the back and hamstring muscles using the apparatus illustrated in  FIGS. 8 and 9  according to an embodiment. 
       
    
    
     DETAILED DESCRIPTION 
       [0023]    The following detailed description is directed to certain specific embodiments of the invention. However, the invention can be embodied in a multitude of different systems and methods. In this description, reference is made to the drawings wherein like parts are designated with like numerals throughout. 
         [0024]      FIGS. 1 to 10  of the drawings illustrate embodiments of an exercise/medical apparatus  10 .  FIGS. 2 to 6  illustrate specific individual components  11 ,  12 ,  13 ,  14 ,  15  of the apparatus in more detail.  FIG. 7  is a flow chart that illustrates a method of stretching the hamstring and back muscles using the apparatus  10 .  FIG. 9  illustrates an alternative embodiment of the apparatus  10  that includes a motor.  FIG. 8  is a block diagram of a motor component that can be used with the embodiment of the apparatus illustrated in  FIG. 8 .  FIG. 10  is a flow chart that illustrates a method for stretching the hamstring and back muscles using the motorized embodiment of apparatus  10  illustrated in  FIG. 8 . It will be understood that in one embodiment the reverse side of the apparatus  10  is identical in structure and appearance. 
         [0025]    As best illustrated in  FIG. 1 , the apparatus  10  basically comprises a long center shaft  14 . According to an embodiment, the length of the shaft can be in the range of  30  and  40  inches. In other embodiments, the length of the shaft can be selected to fit the size of the user. In one embodiment, the shaft is extendable and retractable in order to change the length of the device for users of different sizes. 
         [0026]    The adjoining parts  11 ,  12 ,  13 ,  15  connect to the shaft. Foot plate  13  and handle  15  are stationary and affixed to proximate opposite ends of the main shaft  14  allowing them to perform as end caps, handles, and/or hooks. 
         [0027]    Ratchet  11  grip  12  attach to the shaft in a manner allowing for vertical motion up and down the shaft. When all parts are assembled as in  FIG. 1 , squeezing the grip  12  causes the combination of the ratchet  11  and the grip  12  to travel along the shaft  14  towards the foot rest  13 . 
         [0028]      FIG. 2  details a ratchet-like structure  11  used to move the grip  12  up and down the shaft  14 . A large spring  19  is placed between the palm grip  21  and the finger grip  22  portions of the grip  12 . This spring is compressed upon squeezing of the palm  21  and finger  22  grips together. This motion actuates the ratchet to moves the grip  12  and ratchet  11  structures downward along the shaft  14 . The ratchet  11  moves through the use of springs  18 ,  19  and metal plates which lock in place due to the angle they are placed against the shaft. Squeezing the grip changes the angle of the metal plates and compresses the main spring  19  allowing the ratchet to creep slightly down the shaft. Upon release of the grip, the metal plates return to the locking angle thereby holding the ratchet in place. In one embodiment, the ratchet is of the type described in U.S. Pat. No. 4,926,722, hereby incorporated by reference. According to an embodiment, the trigger  20  is pulled to release ratchet system allowing the ratchet system to slide up and down the shaft freely. The trigger  20  can be used to position the ratchet  11  and grip  12  back to a starting position along the shaft  14 . 
         [0029]      FIG. 3  details the grip and ratchet system  11 ,  12  that moves down the shaft  14 . The palm grip  21  is fixed in position relative to the finger grip  22 , which is moveable. The finger grip  22  is squeezed toward the palm grip  21  in order to actuate the movement of the grip and ratchet system. The finger grip  22  is hollow and thereby able to pass over the outside of the palm grip  21  as it is being squeezed. Upon release of the finger grip  22 , the spring-like part  19  pushes the finger grip  22  back into place. 
         [0030]    Alternatively, different types of mechanisms can be used to allow the user to move the grip towards the foot plate. For example, indentations or teeth can be formed in the shaft for use with a ratchet or gear mechanism or the shaft can be threaded to allow for a screw type movement of the grip. 
         [0031]      FIG. 4  details the footplate  13  to be placed under the feet of a user thereby providing the leverage necessary to operate the apparatus. The footplate  13  is secured to the bottom of the shaft  14 . In one embodiment the footplate  13  is comprised of two basic sections, the main plate  23  and the bottom end cap  24  to be made of nonslip material. Alternatively, in other embodiments, other shapes and configurations (e.g., straps) can be used to provide allow the user to apply a restraining force against the shaft. 
         [0032]      FIG. 5  details the shaft  14  upon which the apparatus operates. The shaft can be a single or multiple solid structure  16 . According to other embodiments, other cross sectional shapes for the shaft can also be used (e.g., circular). 
         [0033]    In an embodiment, the shaft  16  is marked with progress lines for the purpose of tracking performance. A performance/progress tracking part (not shown) is attached to the shaft  14  and moves down the shaft  14  when pushed by the grip  11  and ratchet  12  motion. According to an embodiment, the progress tracker can maintain its position along the shaft  14  even after the trigger  20  is used to release the ratchet  11  and grip  12 . The progress tracking part can be used to provide feedback to the user regarding how far along the shaft the position of the grips has been 
         [0034]      FIG. 6  details the handle  15 , also referred to as the top end cap  25 . The handle  15  is attached to the top of shaft  14 . The handle  15  is used for carrying and aesthetic purposes only. The handle  15  is fixed in place and provides no working mechanism or functional purpose during actual use. 
         [0035]      FIG. 7  illustrates a method of stretching the muscles of the hamstring and back muscles using the apparatus described above in  FIGS. 1-6 . To use the device, a person places the footplate under the arches of their feet (step  700 ). The left hand is placed on one grip and the right hand on the other (step  710 ). With knees held straight or as close to straight as possible, the person squeezes the grip with one hand (step  720 ). This squeeze actuates the movement of the ratchet system downward along the shaft. The ratchet system holds it position along the shaft. In an embodiment, the ratchet system holds its position along the shaft with a locking angle which prevents movement up or down the shaft. With each additional squeeze of the grip, the ratchet moves further and further down the shaft towards the footplate creating a stretching effect on the back of the legs including the hamstring muscles and in the muscles of the lower back (step  730 ). The trigger  20  is pulled to release ratchet system allowing the ratchet system to slide up and down the shaft freely and to return the ratchet  11  and the grip  12  to starting position along the shaft (step  740 ). 
         [0036]      FIG. 8  illustrates an alternative embodiment of the apparatus illustrated in  FIG. 1-6  that includes a motor component  811  for moving the grip  12  along the shaft  14 . Like the embodiments illustrated in  FIGS. 1-6 , the motorized embodiment of the apparatus illustrated in  FIG. 8  includes a user-actuated drive mechanism. The user-actuated drive mechanism in  FIG. 8  uses a motor component  811  to move the grip  12  along the shaft  14  instead of the ratchet mechanism  11  used in the embodiment illustrated in  FIG. 1 . 
         [0037]    The finger grip  22  of the motorized embodiment illustrated in  FIG. 8  is squeezed toward the palm grip  21  in order to actuate the motor component  811 , causing the movement of the grip  12  and motor component  811  along the shaft  14 . According to an embodiment, the motor  811  component and the grip  12  continue to move downward along the shaft while the user continues squeezes the grip  12  and stops when the user releases the grip  12 . In some embodiments, the motor is configured to move the grip structure downward along the shaft in a stepwise motion similar to that of the embodiment of  FIG. 1  that includes the ratchet  11 . For example, in some embodiments, the grip can include a button that is pressed when the grip  12  configured to cause the motor to move one step downward along the shaft each time that the user squeezes the grip with his or her hand. 
         [0038]    According to an embodiment, the motor can engage with a gear or set of gears that mesh with the indentations or teeth formed along the shaft in order to move the motor component  811  and the grip  12  along the shaft  14 . Alternatively, the shaft can be threaded to allow for a screw type movement motor component  811  and grip  12  along the shaft  14 . According to some embodiments, a release similar to trigger  20  can be included to cause the motor component  811  to move freely along the shaft to allow the grip slide up and down the shaft freely. For example, the release can be configured to cause the motor component to disengage from the indentations, teeth, or threads with which the motor component engages to move the grips  12  and the motor component  811  along the shaft. The release mechanism can be used to allow the user to move the grips back up shaft to “reset” the device for use in another stretching session. 
         [0039]      FIG. 9  is a logical block diagram of the motor component  811  according to an embodiment. The motor component includes a motor  910 , a button  905 , and a power supply  915 . 
         [0040]    According to an embodiment, the motor  910  can be a direct current (DC) motor or an alternating current (AC) motor depending upon the type of power supply  915  selected. 
         [0041]    According to an embodiment, the button  905  is disposed between the power supply  915  and the motor  910 . In some embodiments, the button  905  can be integrated into the grip  12  so that when a user squeezes the finger grip  22  the button  905  is depressed to complete the circuit between the power supply  915  and the motor  910 . According to some embodiments, the grip  12  can have a button  905  on each side of the finger grips  22  so that if the finger grip  22  on either side of the grip  12  is depressed, the motor  910  is activated. 
         [0042]    In an embodiment, power supply  915  can be an internal power source, such as a battery, for powering the motor  910 . In some embodiments, the internal power source comprises a rechargeable battery pack that placed in a battery compartment of the apparatus  10  (not shown). In some embodiments, the rechargeable battery pack can be charged while installed in the battery compartment of the apparatus  10  by coupling a power cord to the to the apparatus  10  that provides power to the battery pack from an external power source, such as the electrical mains used to provide power to many homes and businesses. According an alternative embodiment, the battery pack may be removable for replacement and/or to be recharged using an external battery charger. In an alternative embodiment, the apparatus  10  can be connected to an external power supply to provide power to the motor  910  via power cord coupled to the motor component  811 . 
         [0043]      FIG. 10  illustrates a method of stretching the muscles of the hamstring and back muscles using the motorized version of the apparatus described above. To use the device a person places the footplate under the arches of their feet (step  1000 ). The left hand is placed on one grip and the right hand on the other (step  1010 ). With knees held straight or as close to straight as possible, the person squeezes the grip with one hand (step  1020 ). Squeezing the grip causes a button in the grip be depressed, completing a circuit to activate the motor, and the motor moves the grip downward along the shaft. With each additional squeeze of the grip, the motor moves further and further down the shaft towards the person&#39;s feet creating a stretching effect on the back of the legs and lower back (step  1030 ). In some alternative embodiments, motor component is configured to move downward along the shaft as long as the user continues to squeeze the finger grip  22 , and releasing the finger grip causes the motor to stop. As described above, some embodiments of the motorized version of the device can include a release similar to trigger  20  that can be used to cause the motor to move freely along the shaft to allow the grip slide up and down the shaft freely. The release mechanism can be used to allow the user to move the grips  12  back up shaft to “reset” the device for use in another stretching session. When the release is actuated, the grip can slide up and down the shaft freely (step  1040 ). According to alternative embodiments, the grip may include a switch or button that, when activated, causes the motor to move the grip assembly to back up the shaft rather than using a release mechanism to disengage the motor from the shaft. 
         [0044]    The above description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles described herein can be applied to other embodiments without departing from the spirit or scope of the invention. Thus, it is to be understood that the description and drawings presented herein represent a presently preferred embodiment of the invention and are therefore representative of the subject matter which is broadly contemplated by the present invention. It is further understood that the scope of the present invention fully encompasses other embodiments that may become obvious to those skilled in the art and that the scope of the present invention is accordingly not limited.