Abstract:
The present invention is dedicated to a calf exerciser including a foot unit having foot-palm and heel support surfaces. The foot unit provides efficient resistance training of calf muscles by permitting both eversion or inversion movements of the foot-palm in synchronization with the plantar flexion dorsiflexion muscular contraction. This is achieved by inclining the foot-palm support surface either towards the exterior or the interior sides of the foot unit, by anteo-posteriolly curving the heel support surface from the foot-palm surface to the bottom of the foot unit and by including a gradual inclination of the heel support surface towards the exterior or the interior sides of the foot unit, thus forming a variable angulation foot sole gradient area. This variable angulation foot sole gradient area accentuates the eversion and inversion movements at the foot-palm and reduces the biomechanical stress by eliminating coronal rotation at the heel.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to a calf exerciser. 
       BACKGROUND 
       [0002]    The world of physical training has greatly evolved over the years, which has seen significant improvements in training equipment and apparatus due to technological innovations as well as a better understanding of the human body. Regardless of this evolution, there are still some cases where the technological development has not followed the course of the evolution in knowledge or new physical training tendencies, and especially in the case of leg resistance training. 
         [0003]    A common complaint from athletes is that of a saturation effect in the muscular development of their calves. For a number of athletes, the muscular development efficiency curve quickly saturates and tends to even decline after a few training sessions based upon conventional training methods. As the calves represent a very important muscular system for many sporting disciplines, and that there are no apparatus or method that significantly improves the efficiency of conventional training methods, there is a reel need to provide such an apparatus. 
         [0004]    Conventional calves resistance training techniques may provide good resistance training in conformance with natural movements if they are properly executed using appropriate equipment. The efficiency of those movements is regretfully limited because the training is geared mainly to the overall muscular system. The muscular contraction of a single specific muscle is very difficult to achieve with those types equipment. As may be seen in  FIG. 1 , the prior-art equipment foot-rest ( 2 ), providing support to the feet ( 4 ) of the user ( 6 ), is not appropriate for effective power and strength training. The flat-uniform surface with a 90 degree support area of the foot-rest ( 2 ) does not provide the necessary stability and comfort for an intense training session, does not restrain adequately the movement of the feet ( 4 ) and does not emphasize proper biomechanical mobility of the ankle joints during the exercise. After a number of repetitions, the feet ( 4 ) have a tendency to move out of alignment with the natural axis of the movement. Furthermore, the rectangular shape of the common foot-rest ( 2 ) causes a pressure line at the metatarsals ( 8 ), which obstructs blood flow, which becomes very uncomfortable for the user ( 4 ). Finally, these foot-rests ( 2 ) do not allow a proper positioning of the feet ( 4 ) in accordance with the specific anatomy and the biomechanics of the leg-ankle-foot musculo-skeletal mechanism. 
       SUMMARY 
       [0005]    Accordingly, there is provided, in accordance with one aspect of the present invention, a calf exerciser including a foot unit having foot-palm and heel support surfaces. The foot unit provides efficient resistance training of calf muscles by permitting both eversion or inversion movements of the foot-palm in synchronization with the plantar flexion dorsiflexion muscular contraction. This is achieved by inclining the foot-palm support surface either towards the exterior or the interior sides of the foot unit, by anteo-posteriolly curving the heel support surface from the foot-palm surface to the bottom of the foot unit and by including a gradual inclination of the heel support surface towards the exterior or the interior sides of the foot unit, thus forming a variable angulation foot sole gradient area. This variable angulation foot sole gradient area accentuates the eversion and inversion movements at the anterior part of the foot (foot-palm) and reduces the biomechanical stress by eliminating coronal rotation at the posterior part of the foot (heel). 
         [0006]    In accordance with another aspect of the present invention, there is provided a calf exerciser comprising: 
         [0007]    at least one foot unit, each of the at least one foot unit comprising: 
         [0008]    a heel section comprising: 
         [0009]    a first heel support surface having an anterior, a posterior, a left and a right edges, the first heel support surface anterior edge forming a first downward left incline from the right edge to the left edge, the first heel support surface posterior edge forming a second downward left incline from the right edge to the left edge and the first heel support surface forming an anteo-posterior curve; 
         [0010]    a second heel support surface having an anterior, a posterior, a right and a left edges, the second heel support surface anterior edge forming a first downward right incline from the left edge to the right edge, the second heel support surface posterior edge forming a second downward right incline from the left edge to the right edge and the second heel support surface forming an anteo-posterior curve; 
         [0011]    wherein the first heel support surface right edge and the second heel support surface left edge are adjacent; 
         [0012]    a foot-palm section comprising: 
         [0013]    a first foot-palm support surface having an anterior, a posterior, a left and a right edges, the foot-palm support surface forming a downward left incline from the right edge to the left edge; 
         [0014]    a second foot-palm support surface having an anterior, a posterior, a right and a left edges, the foot-palm support surface forming a downward right incline from the left edge to the right edge; 
         [0015]    wherein the first foot-palm support surface right edge and the second foot-palm support surface left edge are adjacent; 
         [0016]    wherein the first heel support surface anterior edge and the first foot-palm support surface posterior edge are adjacent; 
         [0017]    wherein the second heel support surface anterior edge and the second foot-palm support surface posterior edge are adjacent. 
         [0018]    In accordance with yet another aspect of the present invention, there is provided a calf exerciser wherein the foot-palm section comprises a single foot-palm support surface having an anterior, a posterior, a left, and a right edges and a pivot having an axis of rotation oriented from the posterior edge to the anterior edge such that the foot-palm support surface may be selectively inclined either towards the left edge or the right edge. 
         [0019]    In accordance with a further aspect of the present invention, there is provided a calf exerciser wherein the support unit includes at least one guide and each of the at least one foot unit further comprises a slider element moveably engageable to the at least one guide and wherein each of the at least one foot unit further comprises a locking element which is operable with the support unit for stopping the foot unit from moving. 
         [0020]    In accordance with a further still aspect of the present invention, a calf exerciser foot unit, comprising: 
         [0021]    a heel support surface having an anterior, a posterior, a first side and a second side edges, the first and second side edges being generally in alignment with an anteo-posterior axis, the heel support surface anterior edge forming a first downward incline from the first side edge to the second side edge, the heel support surface posterior edge forming a second downward incline from the first side edge to the second side edge and the heel support surface forming an anteo-posterior curve; 
         [0022]    a foot-palm support surface having an anterior, a posterior, a first side and a second side edges, the first and second side edges being generally in alignment with the anteo-posterior axis, the foot-palm support surface forming a downward incline from the first side edge to the second side edge; 
         [0023]    wherein the heel support surface anterior edge and the foot-palm support surface posterior edge are adjacent. 
         [0024]    In accordance with a further still aspect of the present invention, there is provided a calf exerciser foot unit with heel support surface anterior and posterior downward inclines at angles between 4 and 15 degrees. 
         [0025]    In accordance with a further still aspect of the present invention; there is provided a calf exerciser foot unit with foot-palm support surface downward incline at angles between 4 and 15 degrees. 
         [0026]    In accordance with a further still aspect of the present invention, there is provided a calf exerciser foot unit with a foot-palm support surface posteo-anterior downward incline at an angle between 0 and 15 degrees. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         [0027]    Embodiments of the invention will be described by way of example only with reference to the accompanying drawings, in which: 
           [0028]      FIG. 1  shows a user training with a prior art calf exerciser. 
           [0029]      FIG. 2  shows a user training with a calf exerciser. 
           [0030]      FIG. 3  is an perspective view of the calf exerciser. 
           [0031]      FIG. 4  is an exploded perspective view of a foot unit. 
           [0032]      FIG. 5  is a perspective view of the assembled foot unit of  FIG. 3 . 
           [0033]      FIG. 6  is a perspective view of the partial foot unit and showing the support surface in the right incline. 
           [0034]      FIG. 7  is a perspective view of the partial foot unit and showing the support surface in the left incline. 
           [0035]      FIG. 8  is a perspective view of a partial foot unit without the foot palm support block and without the side walls. 
           [0036]      FIG. 9  is a perspective view of the partial foot unit and showing a support surface having both a right and a left incline. 
           [0037]      FIG. 10  is a perspective view of a partial foot unit separated into two parts, one having a right incline and another having a left incline. 
           [0038]      FIG. 11  is a perspective view of an alternative embodiment of the foot unit of  FIG. 5  where the side walls are replaced by a support harness. 
           [0039]      FIG. 12  is a side view of a foot unit module. 
           [0040]      FIG. 13  is a perspective view of an incline surface. 
           [0041]      FIG. 14  is a perspective view of a support unit. 
           [0042]      FIG. 15  shows the calf exerciser being used in a free weight configuration. 
           [0043]      FIG. 16  shows an alternative embodiment of the calf exerciser being used in a machine weight configuration. 
       
    
    
     DETAILED DESCRIPTION 
       [0044]    Referring to  FIG. 2 , there is shown a user ( 6 ) training with a calf exerciser ( 10 ) in accordance with a particular embodiment of the present invention. The calf exerciser ( 10 ), as best shown in  FIG. 3 , may comprise two foot units ( 100 ), which may accommodate either foot, one for the left foot and one for the right foot, and a support unit ( 200 ), each of which will be further described below. 
         [0045]    For the sake of clarity the right foot unit is described and as such is generally positioned at the right of the support unit ( 200 ). However, it is to be understood that the left foot unit is similar to the right foot unit but that it is generally positioned at the left of the support unit ( 200 ) and that the lateral and medial references are interchanged. Furthermore, it is also to be understood that the right side and the left side of the foot unit ( 100 ) are in reference to a view from its heel portion to its foot palm portion. Thus, when describing the right foot unit the lateral (external) side corresponds to the right side of the foot unit ( 100 ) and the medial (internal) side corresponds to the left side of the foot unit ( 100 ). Similarly, if the left foot unit was to be described, the medial (internal) side would correspond to the right side of the foot unit ( 100 ) and the lateral (external) side would correspond to the left side of the foot unit ( 100 ). 
         [0046]    Referring now to  FIG. 4 , there is shown an exploded perspective view of a foot unit ( 100 ). In the particular embodiment, the foot unit ( 100 ), positioned at the right side of the support unit ( 200 ), comprises a main module ( 110 ), an anterior block ( 130 ), a foot-palm support block ( 140 ), a rod ( 144 ), a pair of laterally spaced, opposed medial ( 146 ) and lateral ( 148 ) walls, an anterior wall ( 149 ), a set of slider blocks ( 152 ,  156 ) and a locking block ( 160 ).  FIG. 5  shows a perspective view of the various components of the foot unit ( 100 ) assembled. The foot unit ( 100 ) may be made, for example, of polymer, aluminium, steel, composite material, carbon fiber, Kevlar™, fibreglass, hardwood or any combination thereof. 
         [0047]    Referring to  FIG. 6 , a heel lateral (external) incline ( 112 ) and medial (internal) incline ( 114 ), as well as a foot-palm support block ( 140 ) form a main module ( 110 ) support surface ( 150 ) that may support the foot ( 4 ) of the user ( 6 ), imposing either an eversion, i.e. towards the outside, or inversion, i.e. towards the inside, movement during plantar flexion. This eversion or inversion movement may be achieved by inclining the foot-palm support block ( 140 ) either towards the exterior or the interior such that the foot is placed on the exterior (lateral) or the interior (medial) side, respectively, of the main module ( 110 ) support surface ( 150 ). The support surface ( 150 ) may thus provide two different inclinations, each corresponding to a specific muscular region of the calf: the lateral inclination corresponding to calf muscles associated with the eversion movement and plantar flexion such as the lateral gastrocnenius, as shown by the grey zone identified by numeral ( 151 ) in  FIG. 6 , and the medial inclination corresponding to calf muscles associated with the inversion movement and plantar flexion such as the head medial gastrocnenius, as shown by the grey zone identified by numeral ( 153 ) in  FIG. 7 . The heel lateral incline ( 112 ) and medial incline ( 114 ) have a posteo-anterior curvature such that the their intersection with the foot palm support block ( 140 ), when the foot palm support block ( 140 ) inclined laterally or medially, respectively, forms a continuous support surface ( 150 ) and have a 0 degree inclination at the bottom of the main module ( 110 ). The resulting support surface is known as the variable angulation foot sole gradient area. The variable angulation foot sole gradient area has two functions: a first function is to accentuate the eversion and inversion movements at the anterior part of the foot, meaning the part of the foot including the metatarso-phalangeal joint and the toes, which are essential to an efficient resistance workout of the calf muscles and the second function is to reduce bio-structure stress by eliminating coronal rotation at the posterior part of the foot, meaning behind the metatarso-phalangeal joint. In gradually reducing the inclination of the support surface from the toes towards the heel, the support surface ( 150 ) properly copies the biomechanics of the foot. 
         [0048]    In order to induce either an lateral or an medial incline to the foot-palm support block ( 140 ), the main module ( 110 ) further comprises a center pivot spine ( 116 ), as best shown in  FIG. 8 , and two sets of matched inclination support surfaces; a set of lateral inclination support surfaces ( 117 ,  121 ) and a set of medial inclination support surfaces ( 118 ,  122 ). Each set of matched inclination surfaces, ( 117 ,  121 ) and ( 118 ,  122 ), comprises a center support surface ( 117 ) and ( 118 ) and an edge support surface ( 121 ) and ( 122 ). The foot-palm support block ( 140 ) which has a palm positioning area ( 141 ), is positioned on top of the center pivot spine ( 116 ) and is held in place by a rod ( 144 ) passing through a hollow channel ( 142 ) within the foot-palm support block ( 140 ), as best seen in  FIG. 4 , and secured at one end by engaging a posterior receptive cavity ( 124 ) in the main module ( 110 ), and at another end by engaging an anterior receptive cavity ( 132 ) in the front block ( 130 ), which is secured to the main module ( 110 ). In use, when the weight of the user ( 6 ) is biased towards the medial side, the foot-palm support block ( 140 ) pivots towards the inside until it rests upon both the center ( 117 ) and edge ( 121 ) medial support surfaces. Conversely, when the weight of the user ( 6 ) is biased towards the lateral side, the foot-palm support block ( 140 ) pivots towards the outside until it rests upon both the center ( 118 ) and edge ( 122 ) lateral support surfaces.  FIG. 6  shows the foot-palm support block ( 140 ) in the lateral inclination state, while  FIG. 7  shows it in the medial inclination state. As mentioned previously, the description of the main module ( 110 ) as illustrated in  FIGS. 6 and 7  assumes that it is used for the right foot of the user ( 6 ), in the case where the illustrated main module ( 110 ) were to be used for the left foot then  FIGS. 7 and 8  would be showing the foot-palm support block ( 140 ) in the medial and lateral inclination states, respectively. In an alternative embodiment, shown in  FIG. 9 , the foot-palm support block ( 140 ) may be incorporated into the main module ( 110 ) so as to be fixed and have both an lateral incline ( 143 ) and an medial incline ( 145 ). In another alternative embodiment, shown in  FIG. 10 , the main module may be separated in two. In the case where this embodiment is used for resistance training of the lateral part of the calf muscles (eversion movement and plantar flexion), foot unit ( 100   a ) is used for the right foot of the user ( 6 ) and foot unit ( 100   b ) is used for the left foot of the user ( 6 ), both foot units ( 100   a ,  100   b ) creating lateral inclines. In the case where this embodiment is used for resistance training of the medial part of the calf muscles (inversion movement and plantar flexion), foot unit ( 100   a ) is used for the left foot of the user ( 6 ) and foot unit ( 100   b ) is used for the right foot of the user ( 6 ), both foot units ( 100   a ,  100   b ) creating medial inclines. 
         [0049]    Optionally, a pair of laterally spaced, opposed medial ( 146 ) and lateral ( 148 ) walls and an anterior ( 149 ) wall, as best shown in  FIG. 5 , are provided so as to help prevent the foot ( 4 ) of the user ( 6 ) from slipping out of position during use. In an alternative embodiment, shown in  FIG. 11 , the walls ( 146 ,  148 ,  147 ) may be replaced by an adjustment harness ( 149 ) that supports the exterior and the front of the foot ( 4 ) and immobilizes the foot during plantar flexion movements. The height of the adjustment harness may diminish gradually until it is minimal at the heel. There is thus maximum support at the front of the foot and minimum support at the tarsometatarsial articulation. This provides support for the proper execution of the movement as well as the necessary freedom in the final phase of the movement, this freedom being essential to a natural plantar flexion. The adjustment harness ( 149 ) may also be, for example, in the form of a partial training shoe (not shown) 
         [0050]    All of the calves muscle training movements involve hyperdorsiflexion that bends the sole of the foot ( 4 ) in a concave manner. The dorsiflexion curvature of the heel incline surfaces ( 112 ,  114 ) renders this position comfortable by eliminating the pressure line under the foot ( 4 ). This characteristic eliminates the blood blockage sensation usually experienced with conventional foot-rests ( 2 ), such as, for example, the one illustrated in  FIG. 1 . The posteo-anterior curvature ( 111 ) of the heel incline surfaces ( 112 ,  114 ), as shown in  FIG. 12 , is mathematically determined in order to adequately and effectively adapt to the biomechanics of the foot. 
         [0051]    Referring to  FIGS. 12 and 13 , five basic parameters may be used to specify the heel lateral ( 112 ) and medial ( 114 ) inclines; the heel anterior inclination angle β, the heel posterior inclination angle δ, the posteo-anterior curvature ( 111 ), length L and height h. It is to be understood that although  FIG. 13  shows the heel anterior (β) and posterior (δ) inclination angles for the heel medial incline ( 114 ), the same angles apply to the heel lateral incline ( 112 ). The posteo-anterior curvature ( 111 ) may be expressed as a mathematical function of length L and height h such as, for example, the equation of an ellipse: 
         [0000]    
       
         
           
             
               
                 
                   
                     
                       
                         x 
                         2 
                       
                       
                         h 
                         2 
                       
                     
                     + 
                     
                       
                         y 
                         2 
                       
                       
                         L 
                         2 
                       
                     
                   
                   = 
                   1. 
                 
               
               
                 
                   Equation 
                    
                   
                       
                   
                    
                   1 
                 
               
             
           
         
       
     
         [0052]    For practical purposes, the height h may be expressed in terms of length L as: 
         [0000]        h=F×L , where 0.25≦ F≦ 2.  Equation 2
 
         [0053]    In the particular embodiment shown, the length L is set to 110 mm and the proportionality factor F is set to 1.25. As it may be understood, the expression of the posteo-anterior curvature ( 111 ) is not limited to the mathematical function of Equation 1 and may be expressed as, for example, other curvilinear mathematical functions. It may also be understood that different values of length L and proportionality factor F may be selected. 
         [0054]    The remaining parameters β and δ may be both set, in the particular embodiment, at 8 degrees. In alternative embodiments, β and δ may be set from 4 to 15 degrees. In a further alternative embodiment, the foot unit ( 100 ) may be designed such that β and δ are user ( 6 ) adjustable. 
         [0055]    As may be seen in  FIG. 12 , the set of lateral inclination support surfaces ( 118 ) and ( 122 ) may be downwardly inclined in the posteo-anterior axis at an angle θ. It is to be understood that in the event that the set of lateral inclination support surfaces ( 118 ) and ( 122 ) are inclined at an angle θ, even though they are not shown, the set of medial inclination support surfaces ( 117 ) and ( 121 ) will also be inclined downwardly in the posteo-anterior axis at an angle θ. The posteo-anterior inclination of the foot-palm support block ( 140 ) helps to improve the stability and accentuate the hyperdorsiflexion of the foot ( 4 ) during training movements because the increase in angular distance between the heel lateral ( 112 ) and medial ( 114 ) inclines and the foot-palm support block ( 140 ). In the particular embodiment θ may be set at 10 degrees. In alternative embodiments, θ may be set from 0 to 15 degrees. In a further alternative embodiment, the foot unit ( 100 ) may be designed such that θ is user ( 6 ) adjustable. 
         [0056]    Referring back to  FIG. 3 , the two foot units ( 100 ) engage with the support unit ( 200 ). This allows the user ( 6 ) to set the spacing between each foot unit ( 100 ) as best suits him or her. Furthermore, the support unit ( 200 ) provides stability to the calf exerciser ( 10 ) during exercising. 
         [0057]    The support unit ( 200 ), such as in the particular embodiment illustrated in  FIG. 14 , generally comprises a base ( 202 ) supported by a beam ( 204 ) connected to two or more legs ( 206 ,  208 ,  210 ). In an alternate embodiment, the support unit ( 200 ) may not have any legs ( 206 ,  208 ,  210 ) or beam ( 204 ) and thus have its base ( 202 ) lying directly upon a surface. In a further embodiment, the support unit ( 200 ) may be embedded within a Nautilus™ type mechanical structure comprising resistance mechanism such as, for example, a weight stack, elastics, etc. When the support unit ( 200 ) is part of a mechanical structure, the central leg ( 210 ) may be replaced by a connection to the mechanical structure. 
         [0058]    On the base ( 202 ), between two end plates ( 212 ,  214 ) are disposed, in a generally parallel configuration, a set of guides ( 216 ,  218 ) and a rail ( 220 ), the rail ( 220 ) having a number of slots ( 222 ) therein. As may be seen in  FIG. 4 , each main module ( 110 ) comprises a recess ( 126 ) where are located the set of slider blocks ( 152 ,  156 ) which are designed such as to be movably engageable with the set of guides ( 216 ,  218 ) using corresponding openings ( 154 ,  158 ), respectively. This ensures that each foot unit ( 100 ) may move in a single translation axis. 
         [0059]    Also, located in the recess ( 126 ) is a locking block ( 160 ) which is positioned so as to be generally above the rail ( 220 ) when the slider blocks ( 152 ,  156 ) are engaged with the guides ( 216 ,  218 ). The locking block ( 160 ) comprises a locking mechanism ( 162 ) having a handle ( 164 ) operatively connected with a pin ( 166 ) which is biased outwardly from the locking mechanism ( 162 ). The handle ( 164 ) and the pin ( 166 ) are operatively connected such that pulling the handle ( 164 ) as for effect the retraction of the pin ( 166 ) into the locking mechanism ( 162 ). When the slider blocks ( 152 ,  156 ) are engaged with the guides ( 216 ,  218 ), the locking block ( 160 ) is positioned above the rail ( 220 ) in such a manner that the pin ( 166 ) of the locking mechanism ( 162 ) is in alignment with and engages a slot ( 222 ). The foot unit ( 100 ) is thus locked in place when the pin ( 166 ) is engaged with a slot ( 222 ) and may be moved by pulling on the handle ( 164 ), thus retracting the pin ( 166 ) into the locking mechanism ( 162 ), so that the foot unit ( 100 ) is free to move along the guides ( 216 ,  218 ). To lock the foot unit ( 100 ) in place once more, the handle ( 164 ) is released so as to allow the pin ( 166 ) to engage a slot ( 222 ) at the desired position along the rail ( 220 ). 
         [0060]    In use, the particular embodiment of the calf exerciser ( 10 ) may be used in a free weight configuration, as shown in  FIG. 15 , while its alternative embodiment may be used in a machine weight configuration, as shown in  FIG. 16 . 
         [0061]    Although the present invention has been described by way of particular embodiments and examples thereof, it should be noted that it will be apparent to persons skilled in the art that modifications may be applied to the present particular embodiment without departing from the scope of the present invention.