Abstract:
An exercise apparatus and method for applying one or more lateral resistive loads to drive, swing and other phases to participants while performing complex motions at low or high speeds to condition one&#39;s body to better and more quickly perform physical movements at high speeds. Elastic members may be used to generate resistance emanating from a ground-based or vertically-positioned apparatus. The elastic members may connect to one or more body parts simultaneously. The apparatus may be mechanically designed to fully retract the elastic members into the apparatus to maintain resistance while participants are in close proximity to the apparatus. The apparatus provides a plurality of self-contained elastic members and provides participants the ability to alter the vertical and horizontal positions of each elastic member&#39;s emanation point from the apparatus. This provides ability to control applied resistance vectors between the attachment point on the participant and the apparatus.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority under 35 U.S.C. §119(e) from U.S. Provisional Patent Application Ser. No. 61/923,104 filed Jan. 2, 2014, the entirety of which is hereby incorporated by reference herein. This application also claims priority under 35 U.S.C. §119(e) from U.S. Provisional Patent Application Ser. No. 61/976,721 filed Apr. 8, 2014, the entirety of which is hereby incorporated by reference herein. 
    
    
     BACKGROUND 
     The present disclosure relates to apparatus and methods for applying resistance to the movement of a trainee using elastic resistance bands. More specifically, the present disclosure relates to such apparatus and methods where the resistance to the trainee increases substantially linearly while the trainee moves at distances from one to nearly one-hundred fifty feet. 
     Elastic resistance bands are becoming more popular for use in athletic training, physical rehabilitation and general fitness for people of all ages. Elastic resistance has many benefits with the most prominent being the fact that an elastic band can generate many times its weight in resistance and it can bend to compactly fit into very small spaces. Thus, elastic bands are an easily portable exercise means to provide resistance to human training movements when one end of an elastic band is attached to a trainee and the other end is anchored to a fixed object or opposing body part. Though elastic bands have a resistance to weight ratio that can be hundreds of times greater than that of metal weight plates, the increase in the resistance of the band over the distance the band is stretched may be a significant drawback that limits the usefulness of elastic bands to trainees. Most often the increase in resistance as the elastic band is stretched is considerably greater than desired by the trainee. 
     The shorter the band is in its contracted state the greater the percent increase in resistance will be as a function of distance stretched. For example, if you take a one foot long, one quarter inch thick elastic band and anchor one end to a wall and hold the opposite end exactly eleven inches from the wall, the band provides no resistance because the twelve inch band is slack. However, if you stretch the twelve inch band one hundred percent (100%) out to 24 inches the resistance will go from 0 to about 10 pounds. If you stretch the band to two hundred percent of the slack length of the band of 12 inches out to 36 inches, the resistance will increase 150% to about 25 pounds. If you stretch the band to three hundred percent of the slack length out to 48 inches, the resistance will increase 200% increase to about 50 pounds. The resistance required to stretch an elastic band increases exponentially as the stretched length becomes a larger percentage of the slack length of the elastic band. The exponential increase in resistance as a function of distance stretched may be detrimental to many training applications. 
     In many applications, it is desirable to minimize the increase in the resistance applied to a trainee by one or more elastic bands over the length of a training path. The present disclosure presents a light weight portable apparatus that includes elastics that can apply resistance to a trainee within an inch of the apparatus (mimicking a resistance band less than 1 inch long) and then be stretched great distances out to 10, 50, 100 and even in excess of 120 feet before resistance begins to increase nonlinearly. In one aspect of the present disclosure, it is difficult for the trainee to perceive an increase in applied resistance over any incremental 10 foot length that the elastic band is stretched thus providing broad, effective and safe training benefits for physical rehabilitation and athletic training. 
     Two important limitations associated with conventional elastic bands are described below. First, when elastic bands are used in physical rehabilitation settings, often the angle of resistance acting on the patient&#39;s limb for which the elastic is attached is critical during the exercise movement. This requires the point of origin or anchor point of the elastic band to be in close proximity to the patient forcing the physical therapist to use a relatively short elastic bands to maintain the proper angle of resistance while performing the exercise. Unfortunately utilizing a short band as explained earlier, will cause the resistance to increase dramatically through the range of motion from start to finish. Most often, the resistance is not enough at the start of the exercise movement and far too great at the end of the exercise movement. It is very difficult for doctors to estimate the start resistance and finish resistance in these cases and the patients recovering from joint surgery utilizing the bands often cannot complete the full range of the desired exercise movement due to the excessive increase of resistance across the range of movement. 
       FIGS. 1 and 2  illustrate respectively the start and stop position of a common shoulder exercise where the hand starts across the body at the lower left ( FIG. 1 ) and rises to the upper right at a 45 degree angle ( FIG. 2 ). Therapist typically desire to apply resistance at a 45 degree angle throughout this movement from the trainee&#39;s lower left to upper right. To accomplish loading the movement at a 45 degree angle the therapist has no choice when using an elastic band but to anchor one end near the patient at point A as shown in  FIGS. 1 and 2 . In order to apply loading at the beginning of the movement a very short elastic band (EB Short ) is required based on the position of the necessary anchor point A and the fact that the band has to be taut at the start of the exercise movement. Thus the unstressed length of the elastic band must be less than length D. When comparing the distance DS 1  which is the length of the exercise movement to the length of the elastic resistance band which is less than D, it is readily apparent that the exercise band must stretch multiple times its length from the start to finish of the exercise movement (DS 1 =D′−D&gt;&gt;D). As previously explained, stretching an elastic band even 100% of its length will result in a dramatic increase in resistance from the start to finish of the exercise movement for any conventional elastic training band. For the particular exercise shown in  FIGS. 1 and 2 , getting to the  FIG. 2  position with a resistance 2 to 5 times greater than the starting resistance in  FIG. 1  is extremely difficult if not impossible for many trainees to do, especially those trying to rehab after shoulder surgery when the shoulder is weak. 
     This problem of undesired large resistance variations over the range of an exercise movement is well known among physical therapists and sports trainers and they can only avoid the problem by using a resistance band that applies too little load at the start of the exercise but can apply the desired load at the end of the range of movement. Most physical therapists prefer stable non-varying loading through range of motion but as just explained, if they wish to use elastic bands they must usually significantly under-load the start of a movement using a longer band in order to minimize the increase in resistance as the trainee stretches the band and attempts to complete the exercise movement. This loading differential through the range of the exercise movement is most often not desired but it cannot be helped if conventional elastic bands are the choice of exercise resistance. 
     To avoid the problem illustrated in  FIGS. 1 and 2  utilizing elastic bands, a much longer resistance band would be required so that the distance covered during the exercise movement would be a smaller fraction of the exercise band&#39;s unstressed natural length. However, referencing  FIGS. 3 and 4 , if a much longer band is utilized, in order to have resistance applied at the start of the movement in  FIG. 3 , the trainee would have to be placed on a pedestal P to elevate the trainee high enough to make the elastic band EB Long  taut at the start of the exercise but also keep the desired resistance angle illustrated in  FIGS. 1 and 2 . Now the same exercise distance traveled from the start to finish of the exercise movement DS 1  of  FIG. 4 , is a much smaller percentage of the overall band length E of EB Long  shown in  FIG. 3 . The significantly longer elastic band EB Long  used in the training configuration of  FIGS. 3 and 4  would present the Trainee with a significantly smaller change in exercise resistance from the start to finish of the exercise movement between  FIGS. 3 and 4  since the DS 1  distance is a small fraction of the EB Long  length vs multiples of the EB short  length in  FIG. 1 . 
       FIGS. 5 and 6  illustrate how one aspect of the present disclosure obviates the problems described with reference to  FIGS. 1-4 . The module  1  includes one or more long elastic bands  26  in a compact portable unit such that the present disclosure could route said band to the trainee through routing assembly  27 . The module  1  is capable of pre-loading elastic band  26  so that the trainee feels the desired training resistance when positioned as illustrated in  FIG. 5 . The relative length EB R  of the elastic band  26  extending between mechanism  27  and the trainee&#39;s hand is about the same length D as the elastic band EB short  used in  FIGS. 1 and 2 . However, the Effective band length EB EFFECTIVE  may be ten (10) to sixty (60) times greater than EB R  or length D in  FIG. 1 , Hence the exercise travel distance DS 1  shown in  FIGS. 2, 4 and 6  would be a much smaller percentage of the effective band length EB EFFECTIVE  which is actually a band whose physical length is 10 to 60 feet long. The combination of the extended length band  26  and the mechanical innovations carried by module  1  provides a resistance variation so minimal that the trainee would not be able to perceive a change in resistance over the exercise range denoted by DS 1  in  FIG. 6 . The minimization of resistance variations over short and long training ranges presents a novel and beneficial improvement in elastic band training technology that solves the significant problems with the use of conventional elastic bands. 
     The problem of excessive resistance variations over the distance traveled during the training movement can be illustrated in many exercises.  FIGS. 7 and 8  illustrate an exercise training movement which requires the trainee to load their arm while bringing their arm down and across their body from an overhead extended position. For such an exercise to maintain the angle of desired resistance an elastic band EB of length L would have to be anchored to a structure C in the position shown in  FIG. 7 . Stretching EB to length L′ represents a length significantly greater than L which would inherently cause a significant resistance differential in force applied by EB between hand positions illustrated in  FIGS. 7 and 8 . A significant number of people from an average sample set of any populous group would actually not be able to complete the exercise movement for the shown configuration if a starting resistance of 10 pounds was present in  FIG. 7  and then having the trainee subjected to an increase in resistance resultant from the band being stretched about 400% of its natural length as illustrated in  FIG. 8 . 
     Referencing  FIG. 9 , the present disclosure would eliminate the resistance variation problem illustrated in  FIGS. 7 and 8  by providing physical and mechanical means with module  1  and elastic band  20  which is routed through routing assembly  21  to provide an elastic training element with an effective length of 2 to 10 times the length of L′ as illustrated in  FIG. 10 . Hence the resistance variation over the exercise movement range of L′ illustrated in  FIG. 9  utilizing the present disclosure will be nearly undetectable to the Trainee because the stretch distance L′ of band  20  is a fraction of the effective length of band  20  compared the variation of resistance experienced in the  FIGS. 7 and 8  configuration where the stretch distance L′ is multiples of the natural band length of band EB which is less than length L in  FIG. 7 . 
       FIGS. 11 and 12  illustrate a highly popular exercise conducted by athletes to train the hip flexor muscle used to lift the leg while running. With conventional elastic means this exercise can only be performed by strapping a short elastic band between the ankles and anchoring each end of the elastic band to an ankle harness strap. When performing explosive athletic training drills it is very important that the muscles are loaded at the start of the movement as opposed to the load being applied after 40% to 60% of the training movement is completed. Referencing  FIG. 11  it is clear that the elastic band EB 1  anchored to each ankle with AS 1  and AS 2  respectively will be slack and not apply any resistance or a useful magnitude of resistance at the start of the exercise movement at the moment the foot begins to leave the ground. In fact it is a well-known among sports trainers that with this particular exercise, there will be no useful load applied by EB 1  on the AS 2  ankle strap until the knee has completed approximately 50% of the exercise movement which is half the distance between the left knee position in  FIG. 11  and  FIG. 12 . This means half of the training movement will be performed with no load. This is not a desired loading characteristic when performing the majority of training movements for athletic training or rehabilitation purposes. 
       FIGS. 13 and 14  show illustrate one aspect of the present disclosure for providing resistance to a trainee. The module  1  carries elastic bands  20 , 26  which are routed through routing assemblys  21 ,  27  to the trainee. When the exercise movement is initiated, the trainee will feel a constant load from the instant the foot begins upward movement right through the high knee position illustrated in  FIG. 14 . Additionally, as  FIG. 15  illustrates, with an effective length of thirty (30) feet for each band  20 , 26  in  FIGS. 13 and 14 , it would take two 30 foot long conventional bands anchored in the ground and placing the trainee on a 25 foot pedestal with both bands pre-loaded to simulate the load placed on the trainee by the apparatus of the present disclosure through the range of movement in  FIGS. 13 and 14 . Due to the internal routing of additional elastic band length in module  1  for both bands  20  and  26 , the effective length of each band would be many times the distance of movement represented by the difference in the left ankle position of  FIGS. 13 and 14 . Since the distance traveled by the left ankle would be a small fraction of the total band length  20  or  26 , the trainee will not be able to detect any change in applied resistance while raising or lowering either foot. This is a novel and beneficial improvement that modifies how elastic bands interact with trainees to eliminate large resistance variations throughout the exercise movement while providing the ability to set the direction of applied resistance while in very close proximity to the effective anchor point of the elastic member opposite to the end attached to the Trainee. 
     When loading the throwing or pitching movement it is critical that resistance levels stay at a minimum (under 3 pounds) and not increase notably from the thrower&#39;s perspective so that their arm movement can both complete a natural throwing motion and so that they are not destabilized in the middle of the throwing motion by a rapidly increasing resistance.  FIG. 16  shows elastic bands B 1 , B 2 , B 3  and B 4  of approximate length 30 feet would be required to minimize resistance increases throughout the throwing movement. However, to apply resistance from the proper angles the athlete would have to be elevated about 15 feet high on pedestal P and 30 feet from the elastic band anchor points on wall B to load the limbs properly. This is not a practical set up and that is why pitchers use very short bands to exercise their throwing arms and because short bands are used, they rarely if ever load high speed throwing motions with elastics. 
       FIG. 17  shows how one aspect of the present disclosure would effectively apply similar loads of the 30 foot bands in  FIG. 16  but compress the required space by effectively shifting wall B to position B′ within inches of the thrower.  FIG. 18  illustrates how the spatial compression is achieved by attaching two of the present disclosures  1 A and  1 B on structure  20 . Bands  20  and  26  from each unit are routed by routing assemblies  21  and  27  to attachment points  40 ,  41 ,  42  and  43 . Both  FIGS. 16 and 18  training setups apply resistance with minimal increases throughout the throwing motion but the present disclosure will minimize the required space for the exercise and allow a practical exercise configuration relative to  FIG. 16 . 
     Since exercise bands with ¼″ diameters and larger can be stretched from 100% to 200% of their natural length, the present disclosure&#39;s ability to route significant quantities of elastic bandage within the confinements of module  1 , a trainee will now have the ability to begin running within inches of a base support structure and cover over 40 yards while having their leg drive and recovery phases loaded simultaneously.  FIG. 19  shows how the module  1  may be attached to support structure  20  with resistance bands  20  and  26  routed to the trainee through routing assemblies  21  and  27  and finally attached behind the knees with harness  204 . Attaching the bands behind the knees as opposed to the waist allows all the relevant muscles in the legs to be loaded and trained when the leg is on the ground driving (Drive Phase) and when the leg breaks contact with the ground and is propelled through the air forward for the next ground strike (Recovery Phase). All other conventional training systems attaching resistance to the waist which will only load the Drive Phase and neglect training important muscles required to propel the leg through the air after it breaks contact with the ground. With the present disclosure Sprinters can now have useful resistance applied directly to the drive and recovery phases be within inches of the support structure  20  ( FIG. 19 ) and be able to accelerate out past 40 yards achieving much higher training velocities on both the Drive and Recovery phases which has never been achievable with conventional elastic training means. It has been proven that the ability to train at higher velocities with resistance enables athletes to develop power that can be deployed at higher velocities thus providing an advantage improving high speed performance over conventional elastic methods which can&#39;t facilitate the higher training velocities the present disclosure can. 
     The apparatus and methods of the present disclosure obviate the deficiencies found in the prior art. The present disclosure provides novel mechanical apparatus with the ability to minimize increase in applied force of one or more individual elastic bands as the bands are stretched by the trainee from distances of less than one inch to nearly 150 feet. In one aspect, the apparatus of the present disclosure is portable and can be anchored to any suitable support structure on a permanent or non-permanent basis. The invention may comprise a module carrying an enclosed pulley system with multiple elastic bands. The module may be anchored various structures such as a chain link fence, pole or exercise equipment structure such as a squat rack. The points of origin of the resistance vectors that are applied to the trainee by each of the elastic bands may be easily positioned by the user with a Vector Origination Attachment Mechanism (VOAM). The VOAM may be connected to the module may be removable from the module for connection to another structure. If the base module of the apparatus is attached to a chain link fence the VOAM may be designed to clip onto any point on the chain link fence. The elastic bands are routed from the module though the VOAM to the trainee to provide resistance to the trainee. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a trainee performing an exercise 
         FIG. 2  is a trainee performing an exercise 
         FIG. 3  is a trainee performing an exercise on a pedestal in a start position 
         FIG. 4  is a trainee performing an exercise on a pedestal in a stop position 
         FIG. 5  is one embodiment of the present disclosure for performance exercise of  FIG. 1-4   
         FIG. 6  is one embodiment of the present disclosure for performance exercise of  FIG. 1-4   
         FIG. 7  is a trainee performing an exercise training movement 
         FIG. 8  is a trainee performing an exercise training movement 
         FIG. 9  is a trainee performing an exercise training movement 
         FIG. 10  is a trainee performing an exercise training movement 
         FIG. 11  is a trainee performing an exercise 
         FIG. 12  is a trainee performing an exercise 
         FIG. 13  is a trainee performing an exercise illustrating one aspect of the present disclosure 
         FIG. 14  is a trainee performing an exercise illustrating one aspect of the present disclosure 
         FIG. 15  is a trainee performing an exercise on a pedestal 
         FIG. 16  is a trainee performing an exercise on a pedestal 
         FIG. 17  is a trainee performing an exercise on a pedestal 
         FIG. 18  is one embodiment of the present disclosure for performance exercise  16 - 17   
         FIG. 19  is one embodiment of the present disclosure for running exercise 
         FIG. 20  is one embodiment of the present disclosure for running exercise 
         FIG. 21  is a front view of the training module on chain link fence 
         FIG. 22  is a front view of the training module showing bands extended with clips in a vertical position on chain link fence 
         FIG. 23  is a front view of the training module showing bands extended with clips in a horizontal position on chain link fence 
         FIG. 24  is a front view of three training modules on chain link fence 
         FIG. 25  is another front view of three training modules in a different position than  FIG. 24   
         FIG. 26  is a top view of two trainees in a running exercise 
         FIG. 27  is a trainee in a pitching exercise 
         FIG. 28  is two training modules being snapped on to a platform 
         FIG. 29  is two training modules snapped on to a platform 
         FIG. 30  is a trainee doing a barbell lift exercise 
         FIG. 31  is a trainee doing a barbell lift exercise overhead 
         FIG. 32  is a trainee doing a barbell exercise 
         FIG. 33  is a trainee doing a barbell lift overhead 
         FIG. 34  is three trainees doing exercise training movements with multiple training modules 
         FIG. 35  is a side view of the present disclosure of two trainees doing exercise movements 
         FIG. 36  is a side view of a sprinter 
         FIG. 37  is a side view of a sprinter using the present disclosure 
         FIG. 38  is another embodiment of the front view of the training module 
         FIG. 39  is a front view of the training module showing attachment strap connectivity 
         FIG. 40  is a rear view of the present disclosure 
         FIG. 41  is a front view of the training module in travel configuration 
         FIG. 42  is a view of the training module resistant bands wrapped around flanges 
         FIG. 43  is a view of the training modules four adjustable attachment straps as stowed 
         FIG. 44  is a front view of the training module completely stowed 
         FIG. 45  is a view of the base structure of the training module 
         FIG. 46  is a side view of pulley housing 
         FIG. 47  is another view of pulley housing 
         FIG. 48  is a prospective view of the pulley housing 
         FIG. 49  is a view showing the housings 
         FIG. 50  is a perspective view for routing band around entry pulley in the training module 
         FIG. 51  is a perspective view for routing of resistance band 
         FIG. 52  is a chart for training distance 
         FIG. 53  is a view showing the pulley in the training module 
         FIG. 54  is a view of counter clockwise cord routing in module 
         FIG. 55  is a view showing another pulley in the training module 
         FIG. 56  is a view of a twisted elastic band 
         FIG. 57  is a side view of two pulley stacks 
         FIG. 58  is a top view of pulley stacks 
         FIG. 59  is a cross section view from  FIG. 58   
         FIG. 60  is a cross section of  FIG. 57   
         FIG. 61  is a view referencing pulley P 1   
         FIG. 62  is a view referencing Pulley P 2   
         FIG. 63  is a front view of a double bearing swivel assembly 
         FIG. 64  illustrates an elastic band connected to a spring clip 
         FIG. 65  illustrates the pulley system in the training module 
         FIG. 66  illustrates the pulley system in the training module 
         FIG. 67  shows a top view of two pulley stacks 
         FIG. 68  shows a top view of two pulley stacks in  FIG. 67  shifted to the right 
         FIG. 69  illustrates two pulley systems 
         FIG. 70  illustrates two pulley systems 
         FIG. 71  illustrates a pulley stack 
         FIG. 72  illustrates another embodiment to develop hitting power 
         FIG. 73  illustrates another embodiment of the present disclosure 
         FIG. 74  illustrates the resistance provided by the elastic band 
         FIG. 75  illustrates the resistance provided by the elastic band 
         FIG. 76  illustrates the resistance provided by the elastic band 
         FIG. 77  illustrates the resistance provided by the elastic band 
         FIG. 78  illustrates the applied resistance at various distances 
         FIG. 79  illustrates the applied resistance at various distances 
         FIG. 80  illustrates the applied resistance at various distances 
         FIG. 81  illustrates the applied resistance at various distances 
     
    
    
     DETAILED DESCRIPTION 
     With reference to the figures, like elements have been given like numerical designations to facilitate an understanding of the present disclosure which has multiple embodiments. 
     In one aspect, multiple units may be attached to support structures to provide from one to dozens of resistance bands for one or more trainees to utilize. FIG.  21  illustrates one module  1  of the present disclosure attached to support structure  100  (for example, a chain link fence). Other possible structure may include a wall, floor, squat rack or sled. The module  1  is attached to support structure  100  using conventional attachment means  300 ,  301 ,  302  and  303 . Resistance band  20  is routed through VOAM  21  which attaches to support  100  by conventional means such as clip  22 . The VOAM  21  provides the point of origin of the resistance vector provided by band  20  to the trainee. An attachment means  24  (such as a conventional clip) is adapted to be attached to a harness worn by the trainee. 
     Resistance band  26  is routed through VOAM  27  which attaches to support  100  by conventional means such as clip  28 . The VOAM  27  provides the point of origin of the resistance vector provided by band  26  to the trainee. An attachment means  29  (such as a conventional clip) is adapted to be attached to a harness worn by the trainee. 
       FIGS. 22 and 23  illustrate how the VOAMs  21  and  27  may be positioned to change the horizontal and vertical positions of the origin of the resistance vectors allowing the trainee to select the horizontal and vertical elevation from which the resistance vectors will originate. 
       FIG. 24  illustrates how three modules  1 A,  1 B and  1 C may be positioned in close proximity in multiple orientations to provide multiple resistance bands to one or more trainees. 
       FIG. 25  illustrates a three module configuration  1 A,  1 B and  1 C that would provide three resistance bands to each of two sprinters SP 1  and SP 2  loading at the waist and rear side of both knees.  FIG. 26  illustrates how bands  20 A and  26 A from module  1 A would attach to the waist of Sprinters SP 1  and SP 2  respectively while module  1 B&#39;s bands  20 B and  26 B would attach to the right and left leg respectively of sprinter SP 1  while module  1 C&#39;s bands  20 C and  26 C would attach respectively to sprinter SP 2 &#39;s right and left leg. 
       FIG. 27  illustrates how two modules  1 A and  1 B can utilize respective resistance bands to load a pitcher&#39;s throwing motion at full speed. Resistance band  26  from module  1 A attaches to the left bicep using attachment harness BC 1  while band  20  from module  1 B attaches to the left hand using attachment harness WR 1 . Module  1 A band  20  attaches to the right hip of the trainee using attachment harness WH while the final band  26  from module  1 B attaches to the right ankle using attachment means AS 2 . The use of resistance bands that apply approximately 2 pounds of resistance through the full range of the throwing motion enables pitchers and throwers to conduct this drill with proper throwing form at high speed since the highly stable resistance does not disrupt the thrower&#39;s balance and form while throwing. This module configuration on support structure  100  can also be used to attach multiple resistance bands to a bat at different locations along the bat to dynamically load the swinging motion. 
       FIGS. 28 and 29  show how the portable modules can be snapped on to vertical jump and athletic training platforms  510  with foam mat  511  using locking means  517  thru  524  which accept one or more modules. Attachment means  512  thru  517  attached to platform  510  accept VOAMs  21  and  27  so that the resistance vectors of band sets  20  and  26  may be set or located around the perimeter of mat  511 . 
     There are many other applications for the portable resistance modules which will allow them to be integrated into many training environments. Elastic bands are commonly used to resist and assist barbell lifts. As  FIG. 30  illustrates, a similar problem as previously discussed emerges when desiring to use elastics to resist an overhead lift. Band lengths EB 1  and EB 2  are extremely limited since they must be attached to the bar when it is on the ground and the length L between barbell B and ground attachment point EBA or EBB is very short. If the trainee (T) attempts to lift the bar B overhead as pictured in  FIG. 31 , EB 1  and EB 2  resistance would increase exponentially during the lift and probably prohibit the Trainee from completing the overhead lift or causing a safety issue. Referencing  FIG. 32 , attaching module  1 A and  1 B to the ground and pulley assemblies  21  and  27  would allow you to attach resistance bands  20  and  26  with effective lengths 10 to 60 times greater than length L in  FIG. 30 . When lifting barbell B to the  FIG. 33  position the trainee will feel the same relative resistance from the very start to the end of the lift with the bar in the overhead position. Conventional elastic bands will not allow such a force application from the start to finish of the lift illustrated in  FIGS. 32 and 33 . 
       FIG. 34  shows how multiple modules  1 A,  1 B,  1 C and  1 D may be attached to different locations on a squat rack to provide assisted lifts using resistance bands  26 B and  20 C attached to barbell B with attachment means  201  so that resistance force vectors RB and RC pull up on barbell B. Module  1 A provides an upward resistance vector RA for exercises pulling downward while Module  1 D provides downward force vectors RD to exercises where the Trainee pulls upward. Pulley assemblies  21  and  27  can be detached from frame  200  and relocated to different locations on  200  to create resistance vectors from different angles and opposite directions. 
       FIG. 35  illustrates another view point for integrating the present disclosure permanently or as a removable module on or around squat racks. Note moveable pulley assemblies  21  and  27  can relocate to many positions around the support structure  201 . Multiple attachment means on  201  will allow module  1  to be placed in multiple locations and orientations on and around structure  201 . 
     Another embodiment of the present disclosure includes the ability to apply physical queuing to sprinters to automatically correct over-striding. Referencing sprinter R 1  in  FIG. 36 , to achieve maximum sprinting velocity it has been proven the optimum ground strike point must be directly under the sprinter&#39;s center of gravity CG indicated by strike point  502  in-line with CG as shown by reference line RL 1 . One of the most common problems with all sprinters is the tendency to over stride where the foot makes ground contact in front of CG. Referencing sprinter R 2  in  FIG. 36 , strike point  503  in front of reference line RL 1  will cause a braking effect because the foot is moving in the opposite direction of the sprinter when it strikes the ground in front of the sprinter&#39;s CG by distance D which is typically on the order of an inch or even millimeters. This is a very difficult problem for sprinters to correct and they must try to make the over-stride correction mentally while running and responding to voice commands by their track coach to not over-stride. Referencing  FIG. 37 , Sprinter R 3  is over striding with ground contact at point  503  in front of CG by distance D 1 . Referencing the same runner but with the present disclosure mounted to support structure  500  and resistance bands  20  and  26  attached to the sprinter&#39;s legs behind the knees using harness  204 , force vectors F 1  and F 2  created by the resistance bands automatically and immediately drive the foot back before ground strike and cause the foot to strike in the proper ground location under CG at point  502 . 
       FIG. 38  illustrates another embodiment of the present disclosure. Pulley housing cover  10  attaches to pulley housings with screws  11 . Pulley housings under cover  10  are attached to base structure  2 . Mounting strap attachment points are defined by  6 A,  6 B,  6 C an  6 D. Resistance band  20  with attachment means  24  and  24 A passes through VOAM  21  with attachment means  22  and then enters module body through pulley  7  and is routed back and forth between pulley housings located on either end of the module  1 . After traversing back and forth between pulley housings the band  20  exits the right side of base  2  through resistance adjustment cam cleat  4 . The end of resistance band  20  includes attachment means  25 . 
     Resistance band  26  with attachment means  29  and  29 A passes through VOAM  27  with attachment means  28  and then enters module  1  body through pulley  8  and is routed back and forth between pulley housings located on either end of module  1 . After traversing back and forth between pulley housings band  26  exits the left side of base  2  through resistance adjustment cam cleat  5 . The end of resistance band  26  includes attachment means  30 . 
     The module  1  may include a handle  3  for ease of transport. 
       FIG. 39  illustrates attachment strap connectivity on the four corners of base  2 . One to four adjustment straps are utilized to physically connect the present disclosure to any suitable support structure. Adjustable strap  300  connects to connector  6 B. Adjustable strap  301  connects to connector  6 D. Adjustable strap  302  connects to connector  6 A. Adjustable strap  303  connects to connector  6 C. Resistance bands have been omitted for clarity. 
       FIG. 40  shows the rear side of the present disclosure with carrying means  3  and both resistance bands removed. M 1  thru M 6  are keyed slots designed to quickly attach base  2  to keyed slot receptors that have been installed on any suitable support structure. The keyed slots allow physical attachment of base  2  without the use of adjustable attachment straps detailed in  FIG. 39 . Excess bandage (distal ends of resistance bands  20  and  26 ) are stowed in the rear of the unit by wrapping each band around flanges  31  and  32  and then clipping distal ends with attachment means  25  and  30  to receptors  15 ,  16 ,  17  or  18 . Rubber stand-offs  9 B and  10 B are attached to the bottom of base  2  so that the unit rests on the rubber buffers when placed on the ground. 
       FIG. 41  illustrates how the VOAMs  21  and  27  along with resistance bands  20  and  26  and attachment means  24  and  29  are stowed under cover  10  when the unit is packed up into the travel configuration.  FIG. 42  shows how each of the two resistance bands  20  and  26  are wrapped around flanges  31  and  32  with distal ends  30  and  25  finally attached to receptors  15  and  18 . After the resistance bands have been stowed  FIG. 43  shows how the four adjustable attachment straps are stowed by attaching clip ends  305  together and distal clip ends  306  to receptors  15  and  18 .  FIG. 44  illustrates the completely stowed unit ready for transport or storage. It is important to note that harness accessories can also be stowed inside cover  10 . Thus the stowed unit contains everything required to attach the unit to a suitable structure and perform training drills. Also it is important to note that a third forth resistance band can be added to the module. 
       FIG. 45  shows the base structure  2  with cover  1  and resistance bands  20  and  26  removed. Pulley housings  12  and  13  for this particular design hold 9 pulleys each. If it is desired to increase the training range of the present disclosure then the pulley housing will scale up in the number of levels and pulleys housed in each housing so that more bandage can be routed and stored internal to the unit and thus increase the range at which a Trainee can extract bandage. Housing  13  contains entry pulley  7  and stacked pulleys  40  through  47 . Housing  12  contains entry pulley  8  and stacked pulleys  48  through  55 . 
       FIG. 46  shows a side view of pulley housing  12  with pulleys  8 ,  48 ,  49 ,  50 ,  51 ,  52 ,  53 ,  54  and  55 . Separator plates  63 ,  64  and  65  are used to keep resistance bands from derailing off pulleys and getting tangled. 
       FIG. 47  shows a side view of pulley housing  13  with pulleys  7 ,  40 ,  41 ,  42 ,  43 ,  44 ,  45 ,  46  and  47 . Separator plates  60 ,  61  and  62  are used to keep resistance bands from derailing off pulleys and getting tangled. 
       FIG. 48  shows a perspective view of one embodiment of the present disclosure.  FIG. 49  shows housing  12  offset from housing  13  along perspective A of  FIG. 48 . Housing  12  is closer to the viewer than housing  13 . Element ( 1 +) is the first routing with band  20  corning up the back side of pulley  7  and then coming straight at the viewer (+) and then passing over the top of pulley  48  ( 2 +) still moving toward the viewer. The band turns down pulley  48  and then runs away from the viewer ( 3 −) back towards housing  13  entering the bottom side of pulley  40  still moving away from the viewer ( 4 −). It then runs up the back side of pulley  40  and comes over the top straight at the viewer ( 5 +) and then crosses to the bottom side of pulley  49  ( 6 +) coming straight toward the viewer and then moving up the front side of pulley  49  and turning away from the viewer ( 7 −) and heading back to housing  13  and entering the top side of pulley  41  moving away from the viewer ( 8 −). It then turns down the back side of pulley  41  and comes out the bottom toward the viewer ( 9 +) and passes under pulley  50  toward viewer ( 10 +) and then up the front side of pulley  50  and then away from the viewer towards housing  13  ( 11 −). ( 11 −) crosses the module and enters the top of pulley  42  moving away from the viewer ( 12 −) and then down the back side of pulley  42  and out the bottom toward the viewer and housing  12  ( 13 +). 13+ comes across to housing  12  entering the bottom of pulley  51  ( 14 +) moving toward the viewer and then up the front face of pulley  51  and back towards housing  13  ( 15 −). On the way towards housing  13  the band drops and enters pulley  43  moving away from the viewer ( 16 −) and then wraps around the back side of pulley  43  and comes towards the viewer ( 17 +) and exits cam cleat  4  ( 18 +) exit point B. Note there are two counter rotations in this routing where the band makes a “ FIG. 8 ”. This is done to help minimize twisting of the band. 
       FIG. 50  shows the perspective for routing band  26  around entry pulley  8  at point C. Referencing  FIG. 51  band  26  runs up the front side of pulley  8  and then over the top away from the viewer ( 1 −) towards housing  13  and then entering the lower part of pulley  44  ( 2 −). It then runs up the back side of pulley  44  and comes over the top straight at the viewer ( 3 +) and then comes in the top side of pulley  52  towards the viewer ( 4 +). It then comes down the front side of pulley  52  and out the bottom of pulley  52  moving away from the viewer ( 5 −) it then crosses to the top side of pulley  45  ( 6 −) and then moving down the back side pulley  45  and turning towards the viewer ( 7 +) and heading towards housing  12  and entering the bottom side of pulley  53  ( 8 +) moving toward the viewer and up the face of pulley  53  and then over the top away from the viewer towards housing  13  ( 9 −) to the top of pulley  46  ( 10 −) and then down the back side of pulley  46  and out the bottom towards the viewer ( 11 +) to the bottom side of pulley  54  ( 12 +) and up the front side of pulley  54  and back over the top towards housing  13  ( 13 −). Then entering the top side of pulley  47  moving away from the viewer ( 14 −) and then down the back side of pulley  47  and out the bottom towards the viewer and housing  12  ( 15 +). Then crossing to the top of pulley  55  and over the top towards the viewer ( 16 +) and then down the front face of pulley  55  and out the bottom towards housing  13  ( 17 −). Then out cam cleat  5  exiting at point D ( 18 −). 
     In one aspect, the present disclosure provides a novel design to reduce the twisting effect on the elastic bands as the bands are stretched and contracted.  FIG. 53  illustrates a counter clockwise elastic band routing entering the power module at the lower left and moving in a counter clockwise direction as it is routed between pulley stacks and then out the right side of the module.  FIG. 54  shows a close up photo of the elastic band after routing and before it is extracted and retracted from the module.  FIG. 55  shows what the elastic band looks like after pulling band  20  out to a distance of 40 feet and letting it retract back into the module 20 times. All 9 elastic runs became severely twisted. As the twisting increases the elastic bands will loop and tangle upon retraction causing a lock up (see  FIG. 56 ). 
       FIG. 57  shows a side view of a four level clockwise rotational elastic band routing between two pulley stacks where there is no level change on the back side of the stack when the band traverses from Pulley Stack A to Pulley Stack B and a level change on the near side of the stack every time the band moves from Pulley Stack B to Pulley Stack A. Note the dotted line labeled Reference Plane A that cuts through Pulley Stack A and also the dotted line labeled Reference Plane B that cuts through Pulley Stack B.  FIG. 58  shows a top view of Pulley Stacks A and B for the routing illustrated in  FIG. 57 . 
     Referencing  FIG. 59  showing the cross-section from  FIG. 58 , each band traveling from the right side of Stack A to the right side of Stack B does not change elevation. Because there is no elevation change the band rests on the center of each pulley groove on the right side of each pulley stack (see bands centered on dotted Level 1-4 reference lines). However, when an elevation change occurs on the left side of the pulley stacks where each band leaving Pulley Stack B drops one level as it traverses to Pulley Stack A, the bands are forced to move out of center position because of the elevation change. Following band C 1 + leaving Pulley  1  in Stack A coming toward the viewer (+) reaches Pulley  2  of Pulley Stack B (C 2 +). As C 2 + wraps around Pulley  2  it is forced to roll clockwise into position indicated by (C 3 −) (lower left side Pulley  2 , Stack B) which looks like a counter clockwise direction now since the band has turned 180 degrees from C 2 + to C 3 −. When C 3 − leaves Pulley Stack B it must drop to Level 2. The higher elevation of Pulley  2  forces C 4 − to the upper left of Pulley  3  while the lower elevation of Pulley  3  forces C 3  to the lower left of Pulley  2 . As C 4  turns around the back side of Pulley  3  it will have to roll to the center of the Pulley  3  center groove marked by the Level 2 dotted line which again appears as a clockwise rotation from the C 5  perspective. This process repeats its self every time a complete cycle is made around each pulley stack. As the band is extracted out of the power module under tension the rotation effect is greatest in the clockwise direction. As the band is retracted under less tension the band rotation does reverse but all the rotation on the extraction under force is not fully counteracted on the retraction thus for every extraction/retraction cycle there is a net buildup of clockwise twist. If the module design does not compensate for this effect the elastic bands will deform and the module will foul.  FIG. 60  represent one of four design solutions (Counter Rotation) which can be used individually or in conjunction with one another to correct the band twisting issue. 
     In  FIG. 60  Pulley  2  and Pulley  3  are routed the same as in  FIG. 59 . However, when C 5  leaves the right side of Pulley  3  and traverses to Stack B Pulley  4 , it doesn&#39;t go to the right side of Pulley  4 . It instead goes to the left side of Pulley  4  (C 6 +) and now wraps around Pulley  4  in the counter clockwise direction. The counter clockwise direction continues until C 13  leaves the left side of Pulley  7  and crosses over to the right side of Pulley  8  (C 14 +) turning Pulley  8  clockwise. Periodically reversing the band routing direction will counteract the twisting by reversing the roll direction of the band when it drops a level. The number of counter rotations required to reduce band twisting for a power module will depend the number of pulley levels and elevation drop between levels. 
     Another embodiment to reduce band twist is illustrated in  FIGS. 61 and 62 . Referencing Pulley P 1  in  FIG. 61  a conventional concave pulley groove is illustrated which facilitates rolling of the band. If band  350  starts at position A+ because it comes from a pulley of higher elevation and leaves pulley P 1  to a lower elevation then Band  350  will roll from position A+ to E− and twisting will occur. Referencing  FIG. 62 , if the non-conventional pulley groove is designed such that pulley P 2  groove is slotted so that the elastic band  350  wedges into a groove  352  having a slightly narrower width W than the band&#39;s relaxed diameter D and the groove is as deep d as the band is wide, there will be no way for the band to roll. The band will be locked into position upon entering and exiting the pulley regardless of level changes. 
     Referencing  FIG. 63 , a double bearing swivel assembly  310  may be used to allow twisting to self-unwind. Bearing housing BH holds two bearing assemblies  354  allowing both shafts S 1  and S 2  to easily rotate independently.  FIG. 64  shows how elastic band  20  is connected to ringlet R 1  and a spring clip used to attach the elastic band to the Trainee&#39;s harness means is connected to ringlet R 2 . Both R 1  and R 2  spin freely in either direction allowing band  20  to rotate easily in either direction clock wise CW or counter clock wise CCW. Even under load during extraction if a twist build up occurs on extraction the swivel bearing assembly can eliminate it allowing the elastic bands to freely rotate. 
     Another embodiment to eliminate band rolling includes tilted pulleys in each stack in opposite directions.  FIG. 67  shows a top view of two pulley stacks.  FIG. 68  shows a top view of the same two pulley stacks but pulley stack  2  is shifted to the right of the dotted line indicating the centerline between the two stacks. View A reference shall be used when viewing  FIG. 69 . Referencing  FIG. 69 , both sets of pulleys in stack  1  and stack  2  are angles in opposite directions by X degrees such that pulley groove centers line up with opposing pulley stacks. Referencing  FIG. 70 , left side Pulley  1  E 1  elevation line intersects left side pulley  2  center line. Right side Pulley  2  centerline E 2  intersects right side Pulley  3  center groove. Left side Pulley  3  centerline E 3  intersects Pulley  4  left side center groove. This continues so all pulley groove centers match opposing stack pulley centerlines. Referencing  FIG. 71 , when pulley stacks  1  and  2  are realigned as showing in  FIG. 67  there are no elevation drops between stacks now and thus no reason for the elastic bands to roll out of the pulley groove centers. Elevation changes are accomplished when the band is actually resting in the center groove turning around the pulley. 
       FIG. 72  illustrates another embodiment to assist baseball players and tennis players to develop hitting power. Bearings  200 ,  202 ,  203  and  205  with connector means  201 ,  203 ,  204  and  206  respectively allow resistance band connectivity to a bat or racket allowing the handle to rotate 360 degrees continuously while swinging the bat or racket. Connection points are not fixed so bearings allow rotation of the handle during the swinging motion. Also multiple connection points allow multiple band connections to apply leverage in different areas of the bat or racket while swinging. 
       FIG. 73  illustrates another embodiment of the present disclosure where elongated bands  20  and  26  are not routed through pulley systems but are attached to a support structure  100  and utilize the VOAMs  21  and  27  to preload bands  20  and  26  at connection points  24  and  29  using hooks  25  and  30  on distal band ends. 
     As discussed above, a major deficiency in prior art elastic band training apparatus is the unacceptable increase in resistance provided by the elastic band per distance that the band is stretched from its slack state. According to one embodiment of the present disclosure, an apparatus may comprise one or more elastic bands that provide a resistance that increases less than 10% over each five foot increment from a distance starting at one-half foot out to a distance of 135 feet or more.  FIGS. 74-77  illustrate the resistance provided by the elastic band  20  per distance from the origin of the training vector provided by the band. As illustrated, each training vector provided by band  20  originates from VOAM  21 . In each of the figures, the resistance characteristics of band  20  is compared to a band of equal diameter having a length of 3.5 feet. For the band  20 , the zero distance point is 6 inches from the structure holding VOAM  21 . For bands  100 , 101 , 102 , 103  (each having a length of 3.5 feet), the zero distance point is 46 inches from the origin of the vector provided by band  100 , 101 , 102 , 103 . In  FIG. 74 , the band  20  and band  100  each have a diameter of 3/16 inches. In  FIG. 75 , the band  20  and band  101  each have a diameter of ¼ inches. In  FIG. 76 , the band  20  and band  102  each have a diameter of 5/16 inches. In  FIG. 77 , the band  20  and band  103  each have a diameter of ⅜ inches. 
     Another important aspect of the present disclosure is the portability of the training apparatus having the capability of providing the desired resistance over distance. The portability of the apparatus is determined in part by the volume of the module  1 . The module  1  includes the base structure  2  which carries the pulley assemblies. The cover  10  encloses the pulley assemblies to form a rectangular module. In one embodiment, the module  1  has a volume of 0.81 ft 3  and can carry a pair of elastic bands, each having a length of 28 ft. and a diameter ranging from 3/16 inches to ½ inch. 
     In one aspect of the present disclosure, the size of the training apparatus may be determined by inputting certain parameters. The input parameters include: 
     a) Resistance Band Diameter (B Dia ) in inches−Input range 0.1875″ to 0.5″ 
     b) Desired Unit Training Distance in Feet (TR ft .)−Input range=10 to 135 feet 
     c) Distance Stretched (D Stretched ) in feet−Input Range 0&lt;Dstretched&lt;TRft. 
     Certain intermediate parameters may then be determined:
 
Ref LB @6″=[682.667( B Dia3)−384.0( B Dia2)+101.333( B Dia)−8.0]  a)
 
Each band diameter used in the module must be set to a reference resistance level specific to that band diameter within 6 inches of the Module support structure. This set point establishes our zero foot reference point.
 
 R   mod =[0.0000000211( TR   ft .4)−0.00000873( TR   ft .3)+0.001289( TR   ft .2)−0.081912( TR   ft .)+2.78441]  b)
 
This equation determines an elastic coefficient modifier which modifies the elastic properties of each band diameter as the desired training distance is increased and more cordage is integrated into the resistance module.
 
     The volume of the training apparatus and applied resistance at a desired training distance may then be determined as follows:
 
 V (ft 3 )=0.000000235( TR   ft . 3 )−0.000081215( TR   ft . 2 )+0.0180107( TR   ft .)+0.06892232 for (10′&lt; TR ft.&lt;135′)  a)
 
The applied resistance for any given distance stretched over the Desired Training Range (TR ft ) is a function of Band Diameter (B Dia ), Distance Stretched (D Stretched ) in ft., the Set Reference force in lb. within 6″ of the module support structure (Ref LB @6″) and the Elastic Coefficient modifier (R Mod ). Given those inputs the force measured at any point in the Desired Training Range will be less than the value determined by the given equation:
 
 R   Applied =(136.53333( B   Dia   3 )−128.0( B   Dia   2 )+42.67( B   Dia )−4.0)×( R   Mod )×( D   Stretched )+Ref LB @6″  b)
 
       FIGS. 78-81  illustrate the applied resistance at various distances from the reference point for elastic bands of different diameters. The reference point is determined as one half foot from the origin of the training vector provided by the elastic band. The various volumes of the module  1  required to house the elastic cord and pulley assemblies to provide the applied resistance is shown on the figure. 
       FIG. 52  shows a table illustrating the various parameters of training apparatus determined by the method described above according to one aspect of the present disclosure.