Abstract:
An exercise device for stretching the calf muscles and Achilles tendon of a user. The exercise device includes a rod with a pair of grips, a pair of straps, and a foot platform. The pair of straps has two ends; or a first end and a second end. The first end of each strap is affixed to opposing distal ends of the rod. The second end of the pair of straps is affixed to distal, or outside, ends of the foot platform. The exercise device can have a rotatable sleeve with a plurality of surface protuberances on the sleeve. The rotatable sleeve is mounted on the rod between the pair of grips. The rotatable sleeve can be used as a massager by rolling the sleeve over a muscle while gripping the grips on either side of the sleeve.

Description:
FIELD OF INVENTION 
     This invention relates generally to exercise and rehabilitation devices. More specifically, this invention relates to a lightweight, portable and easy-to-use device for stretching the muscles and tendons along the back of a user&#39;s leg. 
     BACKGROUND OF THE INVENTION 
     Stretching devices for therapy and injury prevention have become important tools for the injured and for athletes. Many of these devices target key muscles or muscle groups, such as the muscle groups of the back of the calf or the thigh. Some of these devices are quite complicated or bulky. For example, U.S. Pat. No. 4,693,470 to Ogawa teaches a stretching device having an angled standing surface that a user stands on to stretch their Achilles&#39; tendons and calves. By varying the angle of the standing surface relative to the ground a user can adjust the degree of stretch created when standing on the device. However, adjusting the angle appears to require stepping off of the device, manipulating the device to achieve a new angle, and stepping back on the device. Accordingly, a user cannot easily increase the stretch during use as muscles and tendons become looser. In addition, the device is bulky, which reduces it portability. 
     U.S. Pat. No. 6,110,078 to Dyer teaches a passive stretching device for plantar fascia. The device has two hinged plates with a variable tensioning mechanism. A user secures their foot and lower leg to the device and the distal ends of the opposed plates are pulled together with a spring. As with the &#39;470 device to Ogawa, this device is bulky and is not amenable to quick changes in the force applied to the stretching as the muscles become looser. U.S. Pat. No. 5,853,354 (“the &#39;354 patent”) to Kubota teaches a similar device. The device of the &#39;354 patent includes a part that straps to the lower leg of a user and a footplate, with the two parts connected by a hinge. Force is applied by the user to pull the footplate towards the user resulting in dorsiflexion of the user&#39;s foot. Again, this is a bulky device and must be strapped to the user&#39;s foot and lower leg prior to use. 
     Other, more simple, devices exist to aid in stretching. For example, U.S. Patent Application Publication No. 2012/0040808 A1 (“Pub. No. &#39;808”) to Khademi describes a stretching and exercise device with a plurality of strap members, including strap members designed to hold a user&#39;s foot and a strap member designed to be grasped by a user. Pub. No. &#39;808 describes the device as a “stretching and exercise device adapted for lower body muscle stretch, including the user&#39;s lower back and legs” or alternatively, “a stretching and exercise device adapted for isolating and exercising the foot/calf or hamstring/hip muscles of an individual in an efficient and effective manner.” This device employs a complicated system of straps and a plate to stretch the lower calf muscles, and is only capable stretching a single leg at a time. 
     A number of devices employ multiple straps and/or handles to allow a user to stretch a single leg. For example, U.S. Pat. No. 4,456,249 (“the &#39;249 patent”) to Calabrese teaches a stretching apparatus with two ropes extending from a collar fitting over the head or neck of a user to a foot-receiving stirrup. The ropes have separate handgrips. A user puts one foot in the stirrup and pulls the handgrips to stretch various muscles and tendons while the device is anchored around the head or neck of a user. U.S. Pat. No. 5,518,486 (“the &#39;486 patent”) to Sheeler teaches an exercise device for a variety of exercises, including stretching. The device includes a foot loop, a hand grip, and an adjustable strap linking the foot loop to the harness. The device only allows for stretching a single leg at a time. 
     These devices tend to be complicated by the number of straps and/or they lack portability. In addition, the devices are designed solely for stretching and do not address other muscle issues, such as soreness, that can be resolved by massaging. The present invention overcomes these limitations and shortcomings of the prior art with the rear chain stretcher as described in detail below. 
     SUMMARY OF THE INVENTION 
     The long-standing but heretofore unfulfilled need for a portable, uncomplicated stretching device is now met by a new, useful, and nonobvious invention. The novel device further advances the art through the addition of embodiments including a massaging element integral to the device, thereby allowing a user to have a single device for stretching and working out soreness in muscles. 
     In a first aspect the present invention provides an exercise device for stretching the calf muscles and Achilles tendon(s) of a user. The exercise device includes a rod, or handle, with a pair of grips, a pair of straps, and a foot platform. The pair of straps have two ends; or a first end and a second end. The first end of each strap is affixed to opposing distal ends of the rod, or the portion of the rod towards either end of the rod. The second end of the pair of straps is affixed to distal, or outside, ends of the foot platform. In certain embodiments the length of the strap can be adjustable to tailor the device to the flexibility or height of the user. The foot platform is designed to be wide enough so that the balls of a user&#39;s feet can fit on the platform simultaneously. The grips on the rod are designed to be grasped by the hands of a user; in particular, gripping the grips and pulling the rod towards the abdomen or chest of the user will allow a user to create dorsiflexion of the user&#39;s feet. 
     The rod can be hollow and have a pair of end caps that removeably engage ends of the rod, such as by the threading of the end caps onto the rod. This can be used to secure the straps to the rod, such as when the straps have a loop at the end and the loop is just barely big enough to fit over the rod but not large enough to fit over the end caps. The interior space of the hollow rod can have one or two walls or dividers within the hollow space to create compartments thereby allowing storage of articles within the compartments of the rod by removing and replacing an end cap. 
     In addition, the strap width can be made narrower than the inner diameter of the rod and/or buckle. This allows the straps to be stored within the inner cavity of the rod when not in use. 
     In an advantageous embodiment the exercise device of the first aspect can include a rotatable sleeve with a plurality of surface protuberances on the sleeve. The rotatable sleeve is mounted on the rod between the pair of grips. The rotatable sleeve can then be used as a massager by rolling the sleeve over a user&#39;s muscle while gripping the grips on either side of the sleeve. 
     As discussed above, the strap length can be adjustable. Each strap can consist of two strap members linked by a buckle and the strap length can be adjusted by moving the buckle to a different position on one of the strap members. 
     In certain embodiments the rod is about 40 cm. to about 70 cm. long. For example, the rod can be about 40 cm., about 45 cm., about 50 cm., about 55 cm., about 60 cm., about 65 cm. or about 70 cm. in length. This approximates the width of a user&#39;s shoulders, allowing the user to more comfortably grasp the bar. In other words, the grips would be about shoulder width at their outer ends, with additional length on either end of the rod to accommodate the straps and endcaps. In an advantageous embodiment, the rod is about 55 cm. to about 65 cm. in length. 
     The foot platform can have a surface shape that conforms to the balls of a user&#39;s feet, such as a concave surface shape. The surface of the foot platform can also be textured or cushioned to help prevent slippage of the user&#39;s feet. The width, or length, of the foot platform will be roughly the same as the length of the rod. 
     In a second aspect the present invention provides a second exercise device. The exercise device of the second aspect, like the device of the first aspect, has a rod with a pair of grips, a pair of straps, and a foot platform. In the second aspect the rod is hollow and has a pair of end caps that removeably engage ends of the rod and secure the straps to the rod. The hollow rod can have one compartment, such as that between the interior of the rod and the two endcaps, or the rod can have a plurality of compartments, thereby allowing storage of articles within the rod by removing and replacing an end cap. The plurality of compartments can be created by having walls or dividers within the otherwise hollow handle. In an advantageous embodiment the strap width is narrower than the inner diameter of the rod. This allows the straps to be stored within the rod when not in use. In addition, the width of the buckles can also be narrower than the inner diameter of the handle to facilitate storage. 
     In a third aspect the present invention provides a third exercise device. The exercise device of the third aspect, like the device of the first aspect, has a rod with a pair of grips, a pair of straps, and a foot platform. In the third aspect the exercise device has a rotatable sleeve with a plurality of surface protuberances. The rotatable sleeve is rotatably coupled to the rod between the pair of grips. In other words, it is on the external surface of the rod in between the grips and is capable of rotation when the grips are held by a user and the sleeve is moved along the user&#39;s body. The surface protuberances can be various shapes, such as knobs. It is found that such protuberances enhance the massage effect. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a fuller understanding of the invention, reference should be made to the following detailed description, taken in connection with the accompanying drawings, in which: 
         FIG. 1  is a front elevation view of a rear chain stretcher according to an embodiment of the invention. 
         FIG. 2  is a side elevation view of the embodiment of the rear chain stretcher shown in  FIG. 1 . 
         FIG. 3  is a side view of a person using the embodiment of rear chain stretcher shown in  FIG. 1 . 
         FIG. 4  is a top plan view of the foot platform of the embodiment of the rear chain stretcher shown in  FIG. 1 . 
         FIG. 5  is a bottom plan view of the foot platform of the embodiment of the rear chain stretcher shown in  FIG. 1 . 
         FIG. 6A  is a front elevation view of a section of the handle and end cap of the embodiment of the rear chain stretcher shown in  FIG. 1 .  FIG. 6A  shows the end cap removed from the handle of the rear chain stretcher. 
         FIG. 6B  is a perspective view of a section of the handle and end cap of the embodiment of the rear chain stretcher shown in  FIG. 1 .  FIG. 6B  shows the end cap removed from the handle of the rear chain stretcher. 
         FIG. 7  is a side elevation view of the strap system of the rear chain stretcher shown in  FIG. 1 . 
         FIG. 8  is a front elevation view of a handle of an alternative embodiment of a rear chain stretcher according to the invention. The embodiment has a massage element between the pair of grips. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to  FIG. 1 , the rear chain stretcher  10  has a handle  20 , a foot platform  40 , or foot panel, and a pair of straps  30  joining the foot panel  40  to the handle  20 . The handle  20  is designed to be grasped by the hands of a user. To facilitate grasping the handle  20  by a user, the handle  20  has a pair of grips  22  on the surface of the handle  20 . The grips  22  have a surface texture to enhance the ability of the user to grasp the grips without the handle slipping in the user&#39;s hands. The handle  20  has a pair of end caps  24  at opposing ends of the handle. The end caps  24  thread onto threads  26  on the handle  20  as shown in  FIGS. 6A and 6B . Handle  20  has a hollow interior, which allows the straps  30  to be stored inside the handle  20  when the rear chain stretcher  10  is disassembled. Additionally, a user can store small objects, such as car keys, inside the handle  20  by placing the objects in the interior of the handle and affixing the end caps. 
     Returning to  FIG. 1 , the rear chain stretcher  10  has a pair of straps  30  affixed to the handle  20 . Strap  30  is composed from a first strap member  30   a  and second strap member  30   b  joined by a slip-lock buckle  34 . Slip-lock buckle  34  has an essentially square frame and a pair of bars (not shown) extending between two opposing sides of the frame. The buckle  34  is composed of plastic, although other materials, such as various metals, can be used. Strap member  30   a  has a length of about 26.0 cm, a width of about 1.9 cm, and is securely affixed at one end to slip-lock buckle  34  and at the other end to handle  20 . An end of strap member  30   a  is looped over one bar of slip-lock buckle  34  and sewn onto itself to affix the strap  30   a  to the buckle  34  and close the loop. The opposite end of strap  30   a  is looped over a distal end of handle  20  and sewn onto itself to affix the strap  30   a  to handle  20  and close the loop as shown by element  32 . 
     Strap member  30   b  has a total length of about 65.0 cm, a width of about 1.9 cm, and is affixed at one end to the foot platform  40 . Strap member  30   b  slidingly engages the buckle  34 . The overall length of strap  30  can be adjusted by sliding buckle  34  along the length of strap member  30   b . By adjusting the positioning of buckle  34  along strap member  30   b , the overall length of strap  30  can be adjusted from about 30 cm to about 90 cm. Clip  36  surrounds of strap member  30   b  where strap member  30   b  is doubled back to help secure the loose end of strap member  30   b  against the portion of strap member  30   b  where that length extends between foot platform  40  and buckle  34 . 
     In a preferred embodiment strap member  30   a  forms a loop  31  over the exterior surface of the handle  20  and is sewn together, thereby enabling the strap to securely rotate over the surface of the handle. In other words, a junction  32  is formed where a distal end of strap member  30   a  is sewn to the section of strap member  30   s  immediately adjacent to the loop  31 . The handle  20  has end caps  24  which removeably affix to the handle  20  and have a diameter slightly larger than that of loop  31  of the strap member  30   a , thereby preventing loop  31  from sliding off of the end of the handle  20 . 
     Strap  30  can be composed of any flexible, strong, inelastic strap material. Web-type straps made of polypropylene or nylon are preferred as they are strong, abrasion-resistant, inelastic and available in a wide variety of widths, thicknesses and colors. The thickness and width of the strap can be selected to suit the desired strength and flexibility of the rear chain stretcher for a particular user or mode of use. For example, a thinner or narrower strap will provide greater flexibility of the strap at the expense of the tensile strength of the strap. In a preferred embodiment strap  30  is a 1.9 cm to 2.5 cm (i.e. 0.75 to 1-inch) wide polypropylene, web-type strap that is approximately 0.15 cm to 0.18 cm (i.e. 0.060 to 0.070 inch) thick. 
       FIG. 2  is a side a side elevation view of the embodiment of the rear chain stretcher shown in  FIG. 1 . The side view shows the handle  20  and foot platform  40  joined by the strap  30 . The strap  30  has a first strap member  30   a  and second strap member  30   b  joined by a slip-lock buckle  34 . The second strap member  30   b  has a clip  36  to tie down the loose end of the second strap member  30   b.    
       FIG. 7  is a side elevation view of the strap  30 , but lacking the handle  20  and foot platform  40  as shown in  FIG. 2 . The first strap member  30   a  has a loop  31  at the end of the strap. The loop  31  is designed to slide onto the end of the handle  20  and be locked in place by an end cap  24  (See  FIGS. 6A and 6B ). Inward movement of the loop  31  on the handle  20  is limited by the grip  22  and outward movement is limited by the end cap  24  when the end cap  24  is in place on the handle  20 . The diameter of the loop  31  is just large enough so that it can slide onto the handle  20 , but the diameter is smaller that the diameter of the grip  22  or the end cap  24 . In addition, the fit of the loop  31  on the handle  20  allows for some rotation of the loop  31  over the handle  20  when the calf stretcher  10  is fully assembled. The end of second strap member  30   b  is doubled-over and sewn onto itself to form strap limit  38 . This limits the end of the strap from pulling through the slot  44  of the foot platform  40  (See e.g.  FIGS. 4 and 5 ). 
       FIG. 3  is a side view of a user  60  performing a calf muscle stretching exercise using the rear chain stretcher  10  using the first embodiment of the device as shown in  FIG. 1 . The user  60  will assume a seated position with their legs flat, or straight out, on a floor and their back resting against a wall. The user  60  positions the foot platform  40  on the balls of the user&#39;s foot and grasps the grip  22  of the handle  20  with both hands. With the straps  30  taught between the handle  20  and the foot platform  40 , the user  60  will gently, but firmly, pull the handle  20  towards the user&#39;s abdominal region, while maintaining straight legs. This pulls the foot platform  40  towards the trunk of the user  60 , resulting in dorsiflexion of the user&#39;s ankle, and resultant stretching of the user&#39;s calf muscles when the legs remain straight (i.e. with the user&#39;s legs remaining straight by resisting the pull created by the user  60  through the handle  20 ). The length of the straps  30  can be adjusted to accommodate the user&#39;s height and preferences by moving strap  30   b  through buckle  34 . So for example, a taller person, or a person preferring to use the rear chain stretcher  10  with their elbows in a more flexed position, can adjust the straps  30   b  to be longer, while a shorter person, or a person preferring to use the rear chain stretcher with their arms extended and with less flex in their elbows, can adjust the straps  30   b  to be shorter. 
       FIGS. 4 and 5  show the top and bottom, respectively, of the foot platform  40 . With respect to  FIG. 4 , the top  42  of the foot platform  40  can have a concave shape to conform to the balls of a user&#39;s foot. The foot platform top  42  can also have a cushioned or textured surface to protect a user&#39;s foot and prevent slippage. The foot platform  40  has a pair of slots  44  through which the second strap member  30   b  is affixed. 
       FIG. 8  illustrates an alternative embodiment of the handle  20  of the rear chain stretcher  10 . The handle  20  has a massaging roller  28  between the two opposing grips  22  of the handle  20 . The massaging roller  28  is designed to rotate around the handle  20  when a user presses the roller  28  against their body and moves the handle  20  along the plane of the user&#39;s body. In this manner the user is able to massage muscles through the applied pressure of the massage roller  28 . The massage roller  28  has a plurality of knobs, or protuberances, on the surface of the roller to enhance the application of pressure. 
     Glossary of Claim Terms 
     As used throughout the entire application, the terms “a” and “an” are used in the sense that they mean “at least one”, “at least a first”, “one or more” or “a plurality” of the referenced components or steps, unless the context clearly dictates otherwise. 
     The term “and/or” whereever used herein includes the meaning of “and”, “or” and “all or any other combination of the elements connected by said term”. 
     The term “about” or “approximately” as used herein means within 20%, preferably within 10%, and more preferably within 5% of a given value or range. 
     Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the disclosure are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contain certain errors necessarily resulting from the standard deviation found in their respective testing measurements. Furthermore, when numerical ranges of varying scope are set forth herein, it is contemplated that any combination of these values inclusive of the recited values may be used. 
     As used herein, the term “comprising” is intended to mean that the products, compositions and methods include the referenced components or steps, but not excluding others. “Consisting essentially of” when used to define products, compositions and methods, shall mean excluding other components or steps of any essential significance. Thus, a composition consisting essentially of the recited components would not exclude trace contaminants and pharmaceutically acceptable carriers. “Consisting of” shall mean excluding more than trace elements of other components or steps. 
     All references cited in the present application are incorporated in their entirety herein by reference to the extent not inconsistent herewith. 
     It will be seen that the advantages set forth above, and those made apparent from the foregoing description, are efficiently attained and since certain changes may be made in the above construction without departing from the scope of the invention, it is intended that all matters contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense. 
     It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween. Now that the invention has been described,