Patent Publication Number: US-8123661-B2

Title: Portable isometric exercise device and method

Description:
This application is a divisional of U.S. patent application Ser. No. 12/604,184, filed Oct. 22, 2009, which is a continuation of U.S. patent application Ser. No. 11/786,938, filed Apr. 13, 2007, now U.S. Pat. No. 7,608,016, the entireties of which are incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention is related to the field of exercise devices which provide an isometric exercise through a fixed resistance. 
     2. Description of the Prior Art 
     The following 10 patents and published patent applications are the closest prior art references which are related to the present invention. 
     1. U.S. Pat. No. 4,557,480 issued to Edmond R. Dudley on Dec. 10, 1985 for “Portable Exercise Device” (hereafter the “Dudley Patent”); 
     2. U.S. Design Pat. No. Des. 343,881 issued to Andy S. Wilson on Feb. 1, 1994 for “Isometric Exerciser” (hereafter the “Wilson Design Patent”); 
     3. U.S. Pat. No. 5,486,149 issued to Fred T. Smith et al. on Jan. 23, 1996 for “Friction Resistance Exercise Device” (hereafter the “Smith Patent”); 
     4. U.S. Pat. No. 5,489,251 issued to Sherman U. Robles, Jr. on Feb. 6, 1996 for “Exercise Device” (hereafter the “Robles Patent”); 
     5. U.S. Pat. No. 6,123,652 issued to Renate Perleberg-Kolbel on Sep. 26, 2000 for “Levered Resilient Strength Training Apparatus” (hereafter the “Perleberg-Kolbel Patent”); 
     6. U.S. Pat. No. 6,149,559 issued to Teri R. Mackey on Nov. 21, 2000 for “Variable Resistance Exercise Device” (hereafter the “Mackey Patent”); 
     7. U.S. Pat. No. 6,238,324 issued to Gordan A. MacMillan on May 29, 2001 for “Elastic Exerciser System” (hereafter the “MacMillan Patent”); 
     8. United States Published Patent Application No. 2002/0086779 issued to William T. Wilkinson on Jul. 4, 2002 for “Resistance Devices, Total-Body Exercise Machines Outfitted Therewith, And Exercise Methods Using Such Devices And Machines” (hereafter the “Wilkinson Published Patent Application”); 
     9. United States Published Patent Application No. 2003/0134728 issued to Shen Yi Wu on Jul. 17, 2003 for “Exercise Machine” (hereafter the “Wu Published Patent Application”); 
     10. United States Published Patent Application No. 2005/0233875 issued to Raymond Clarke et al. on Oct. 20, 2005 for “Office Gym Exercise Kit” (hereafter the “Clarke Published Patent Application”). 
     The Dudley Patent is a portable exercise device. Specifically, there is a take up reel  14  which has a spring mechanism which causes it to unrewind in the counterclockwise direction and there is a cord  18  which is wound on the reel and extends through a pair of wedges  22  and  23  and out of the wedges so that the cord can be attached to an exercise mechanism such as a bar  36  or a leg strap  37 . The resistance is changed by having a frictional engagement between the two wedges  22  and  23  adjusted so that they can more tightly compress the cord to cause the resistance to be greater. 
     The Wilson Patent is described as an isometric exerciser but it is a design patent. There appears to be some resistance mechanism within the housing from which two straps extend to special hand grips. 
     The Smith Patent discloses a concept of having an adjustable exercise apparatus wherein the amount of resistance is varied by rotating a dial  54  which has an annular opening  55 . Teeth  56  are disposed around the annular opening  55 . The teeth mesh with teeth on the outer periphery of a collar  60 . The collar  60  is provided with a threaded opening  62  which meshes with the threaded periphery  64  of the shaft  66 . The shaft  66  extends through an opening in the bearing  44  to the opposite surface of the casing  12 . The shaft  66  has a head  70  at its opposite end with the head resting against the flange  72  on the bearing. The Patent further discloses “When an individual desires to use the exercise apparatus  10 , such individual disposes the loop  28  around the post  29  ( FIG. 1 ) and disposes his or her hand or foot in the loop  36  in the cable  32 . The individual then pulls the cable  32  outwardly from the casing. This causes the fan blades  39  to rotate and the helical spring  38  to become constrained. The one-way clutch  42  rotates with the fan blades  39  and drives the disc  46  against the friction force imposed by the bearing liners  52 . The force imposed by the bearing liners  52  against the disc  46  remains substantially constant throughout the rotation of the disc. When the cable  32  is released, the constraint of the spring  38  produces a rotation of the one-way clutch  42  and the fan blades  39  and the sleeve  34  in a direction to release the constraint on the spring. However, the clutch  42  is decoupled from the bearing  44  so that the bearing and the disc  46  do not rotate. The cable  32  becomes wound uniformly on the periphery of the sleeve  34  as the sleeve rotates, as indicated schematically in  FIG. 8 . Successive loops are then provided in a successive layer in the space between successive pairs of the first loops”. “The magnitude of the friction force imposed by the bearing liners  52  against the disc  46  during the rotation of the disc may be adjusted by rotating the dial  54  ( FIGS. 3 ,  4  and  7 ). This rotation causes the shaft  66  to rotate so as to vary the force imposed by the head  70  on the shaft against the flange  72  on the bearing  44 . Since the bearing  44  is coupled to the disc  46 , the force exerted by the disc against the bearing liners  52  is correspondingly varied.” Therefore, this device shows a means for varying the resistance. 
     The Robles Patent is an exercise device for the foot and discloses a harness  12  placed about a foot and a second harness  18  placed about the thigh so that the lower calf muscles can be exercised. The adjustment mechanism to adjust the tension is illustrated in  FIG. 4 . The tension mechanism consists of a spring  58  which is retained between end spring plate  62  and movable plate  64  which is attached to an adjustable rotating rod  72  which can be rotated by a handle. As the rod is rotated in one direction, the plate causes the spring to compress greater and as the rod is rotated in the other direction, the plate  64  moves away from plate  62  to extend the spring to a larger amount of spring force to increase the compression force of the spring. Therefore, this patent discloses the concept of having the spring mechanism adjusted by an adjusting mechanism such as a rotating rod that increases the length or the length of the spring to increase or decrease the compression force of the spring. 
     The Perleberg-Kolbel Patent embodies the concept of having three springs within bores in the housing and a lever mechanism which can move within a slot  15  within the housing so that the spring force can be varied as the pulling mechanism on the housing is causing a resistance force for exercise. Specifically, as disclosed in the patent, “turning now in detail to the drawings,  FIG. 1  shows an upper portion  2  of the housing  2   a  of the apparatus  1 . This has a maximum force indicator element  3  which is contacted by outermost end  4   c  bent through approximately 90°, of a lever  4 , shown in  FIG. 2 . End  4   c  is at the power arm end  4   e  which is displaced when a pulling force is exerted around the power arm end  4   e  of the one-armed lever. The pulling or holding loop  6  is retained in a groove  8  in the lower portion  9  of the housing by means of a cross member  7 . A longitudinal central plane divides the housing into portions  2  and  9 .  FIG. 2  and  FIG. 4  show the lever  4  as being a rod profile of one continuous arm with narrow cross section and being bent into U-shape with a small radius of curvature. Thus, the arms  4   a  and  4   b  bear against one another and are jointly engaged by the pulling loop  5 . As a result, although the rod profile used has a narrow cross section, the force of resistance of the lever is high enough for the transmission of the exerted pulling forces onto the helical compression springs  10 ,  11  and  12 . This occurs at the working arm end  4   d  of the lever. The springs are disposed in bores  13  of a block-shaped spring housing  14  and can be loaded in the downward compression direction by the lever  4 . This downward direction is the same as that shown by the arrow of force K. The lever bears via its work arm  4   d  against the free ends  10   a ,  11   a ,  12   a  of the helical springs extending out of the bores  13 . A slot-shaped grove  15  of the spring housing acts as a space for the guidance and movement of the lever when a force K is exerted onto the power arm end  4   e  of the lever.” 
     The Mackey Patent is a variable resistance exercise device which basically has a mechanism by which the string which is attached to a flexible reel can be incorporated into a strap that is worn around the waist or a leg as shown in the figures so that the resistance can be pulled with the leg or the arm with the mechanism attached to a wall as shown in  FIG. 6 . With respect to the variable resistance mechanism of this invention, referring to  FIG. 8 , a spring wheel  14  causes cable  4  to retract onto spool  16  and  18 . A flexible spring plate  28  is pushed on by the threaded knob  20  so that the further the knob is turned clockwise, the more resistance is put on the top surface  26  of spool  16  and  18  thereby making it harder for the user to pull on. Therefore, the resistance mechanism in this case is varied by having the plate  28  compress further against the spring assembly to therefore cause the spring to be more compressed and therefore, cause the resistance to increase. 
     The MacMillan Patent is an elastic exerciser system, which consists of a multiplicity of elastic loads such as  10 ,  11 ,  12  and  13  shown in  FIG. 2  which can be coupled together and each having a ring extending therefrom to which handles  25  and  27  can be attached so that the loads can be used to pull on either by having a pair of hands extending through the rings or a pair of feet or ankles extending through the rings to create a tension. 
     The Wilkinson Published Patent Application discloses a retraction wheel mechanism as shown in  FIGS. 2   a  and  2   b  attached to the cord  217  which is in turn attached to the mechanism  219  which can be wrapped around an arm or a leg. The retraction mechanism on the cable  217  is illustrated in  FIG. 2   a  consists of a spring  206  which causes the reel to automatically rewind back onto the spool. Other resistance in addition to the spring is such as caliper arms  211  and  212  which increase the resistance. 
     The Wu Published Patent Application is also a portable exercise machine. It contains a cable or rope assembly which is rewound into the housing by a spring mechanism  23 . In this case, it is a spiral spring that causes the rope to rewind back into the casing after it is extended out by a pulling action by an arm or a leg pulling on the handle assembly  611 . In this case for purposes of the retraction mechanism on one side of the wheel  20 , there is a spiral spring  23  which is installed with a unidirectional bearing  24 . The unidirectional bearing  24  is installed with a friction means. In this embodiment, the friction means is a friction wheel  30 . An outer periphery of the friction wheel  30  is enclosed by a friction strip  31 . The contact between the friction strip  31  and the friction wheel  30  is controlled by an adjust device  40 . On this embodiment, the adjust device  40  if fixed to the body  10  by a fixing frame  41 . The fixing frame  41  is an approximate U shaped plate. The fixing frame  41  has a penetrated hole through hole  411 . An approximate rectangular adjust block  42  is installed in the fixing frame  41 . The adjust block  42  has a threaded hole  421 . The through hole  411  of the fixing frame  41  is passed through by a stud  43 . The stud  43  is received in the long groove  105  of the body  10 . One end of the stud  43  is installed with a button  431 . Another end of the stud  43  has a threaded section  432 . The threaded section  432  is screwed to a screw hole  421  for the fixing frame  41 . One end of the friction strip  31  is firmly secured to the adjust block  42 . By rotating the button  431  to rotate the stud  43 , the adjust block  42  may move upwards or downwards in the fixing frame  41  so as not to rotate. Therefore, the friction force between the friction strip  31  and the friction wheel  30  is adjusted. 
     Finally, the Clarke Published Patent Application is a portable exercise gym. Within the device, a resistance means consists of a flexible fabric with a generally rectangular portion as shown in  FIG. 20  with a multiplicity of apertures  30 . It consists of a bunch of retainers that extend through the flexible fabric that creates the resistance. 
     There is a significant need for an improved isometric exercise device which is simple, portable and provides features not found in prior art exercise devices which provide an isometric exercise. 
     SUMMARY OF THE INVENTION 
     The present invention is a portable isometric exercise device with resistance generated by a spring force including an electronic light or sound indicator to signal that a constant force level is being maintained, comprising a device body and other necessary peripheral parts such as a first and second upper grips linked with a cable or string, and a lower grip. The device body is comprised of an isometric spring force selector incorporated with an electronic light or sound indicator with two electrodes, an interior elongated coil spring which is incorporated with a “U” shaped spring force selection member having top transverse sections which are placed on a top end of the spring wherein one transverse section is further extended to be placed inside of a middle channel of the isometric spring force selector. The device further includes a top cover and a device body bottom cover which is installed with a pulley, wherein the isometric spring force selector and the coil spring are placed inside of the device body. 
     The device body is connected to the peripheral parts, with the cable or string at the middle position slidably connected into an interior channel of the pulley, and the lower grip is looped or chained onto a bottom end of the “U” shaped force selection member. The device works in such way that a user first selects a level of the spring force for the isometric exercise through plugging the electronic light or sound indicator having two electrodes into two paired openings in a row selected among a multiplicity of paired openings positioned in a pattern having two columns and multiple rows which transversely penetrate through the isometric spring force selector. The user then affixes the lower grip at a fixed position such as the ground by inserting the user&#39;s foot through the grip. The user starts to exercise by using his hands to pull on the first and second upper grips. This results in pulling the pulley as well as the device body upward. Therefore, the coil spring installed inside of the device body is compressed by a pulling force from the user. This makes one top transverse section of the “U” shaped force selection member which is placed into the middle channel of the isometric spring force selector slidably move downwardly to electrically contact both two electrodes of the electronic light or sound indicator which are plugged into the pair openings of the isometric force selector. The electrical contact activates an integrated electronic device placed inside of the indicator which drives its electronic light or sound component to send a visual or audible signal. Therefore the signal advises the user that a force output from the user&#39;s body muscles balance the level of the spring force which the user has chosen so that a given level of isometric resistance is maintained. If the resistance is lessened, then the contact is broken and the visual or audible signal terminated so the user knows that the isometric level of resistance has not been maintained. The user has multiple selections of the spring force levels for the isometric resistance since the isometric spring force selector is comprised of multiple paired openings which isometrically correspond to multiple force levels of the spring when it is compressed by the user in the exercise. 
     It has been discovered, according to the present invention, that if a portable isometric exercise device has a device body which is comprised of an isometric spring force selector having multiple paired openings positioned to align the longitudinal isometric spring force selector, wherein the multiplicity of paired openings correspond to a multiplicity of different isometric resistance forces created from a multiplicity of spring force levels of a coil spring when it is compressed by a user in the exercise, then the user can choose any paired openings on the isometric spring force selector to select a specific level of the isometric resistance spring forces for the user&#39;s exercise. 
     It has also been discovered, according to the present invention, that if a portable isometric exercise device has a body comprising an elongated coil spring which is inside the body and is incorporated with a “U” shaped spring force selection member having top transverse members which are placed on the top end of a coil spring, wherein one transverse top member is extended to be placed inside of a middle flat channel with opened sides so that the isometric spring force selector can be slidably moved downwardly aligning the longitudinal direction of the isometric spring force selector when the coil spring is compressed by a user in exercise, then the position of the top transverse member of the “U” shaped spring force selection member which is proportional to a particular force level of the coil spring can be used as an indication that the user outputs a muscle force which reaches the level of the spring force. 
     It has been further discovered, according to the present invention, that if a portable isometric exercise device has a body comprising an elongated coil spring which is inside the body and is incorporated with a “U” shaped spring force selection member having top transverse members which are placed on the top end of the spring, wherein one transverse top member is extended to be placed inside of a middle flat channel with opened sides of the isometric spring force selector so that it can be slidably moved downwardly when the coil spring is compressed by the user in exercise to electrically contact two electrodes of an electronic light or sound indicator which are plugged into two paired openings in a row of the isometric spring force selector, then an integrated electronic device placed inside of the indicator will be activated to drive its electronic light or sound component for outputting light or sound as a signal to advise the user that a given level of isometric resistance force is being maintained and if the force is reduced, the visual or audible signal will be terminated since the electrical contract is broken. 
     It has been additionally discovered, according to the present invention, that if an additional “U” shaped electrical contacting member comprising a bottom electrically conducting arm is used to embrace a transverse top member of the “U” shaped force selection member, then the bottom electrically conducting arm of the “U” shaped electrically contacting member will provide a better electrical contact to two electrodes of the electronic light or sound indicator for securely generating the alarm so that the user will be informed that his muscle outputs a force which reaches a level of the spring force which is chosen for his exercise. 
     It is therefore an object of the present invention to provide a portable isometric exercise device having a device body which is comprised of an isometric spring force selector having multiple paired openings positioned to align the longitudinal isometric spring force selector, wherein the multiple paired openings corresponding to multiple isometric resistance spring force levels of a coil spring when it is compressed by a user in the exercise, so that the user can choose any paired openings on the isometric spring force selector to select a specific level of the isometric resistance spring forces for the user&#39;s exercise. 
     It is also an object of the present invention to provide a portable isometric exercise device having a body comprising an elongated coil spring which is inside the body and is incorporated with a “U” shaped spring force selection member having top transverse members which are placed on the top end of the coil spring, wherein one transverse top member is extended to be placed inside of a middle flat channel with opened sides so that the isometric spring force selector can be slidably moved downwardly aligning the longitudinal direction of the isometric spring force selector when the coil spring is compressed by a user in exercise, so that the position of the top transverse member of the “U” shape spring force selection member which is proportional to a particular force level of the coil spring can be used as an indication that the user outputs a muscle force which reaches the level of the desired isometric resistance spring force. 
     It is an additional object of the present invention to provide a portable isometric exercise device having a body comprising an elongated coil spring which is inside of the body and is incorporated with a “U” shaped spring force selection member having top transverse members which are placed on the top end of the spring, wherein one transverse top member is extended to be placed inside of a middle flat channel with opened sides so that the isometric spring force selector can be slidably moved downwardly when the coil spring is compressed by the user in exercise to electrically contact two electrodes of an electronic light or sound indicator which are plugged into two paired openings in a row of the isometric spring force selector, so that an integrated electronic device placed inside of the indicator will be activated to drive its electronic light or sound component for outputting light or sound as a signal to advise the user that his muscle outputs a force to reach a level of the isometric resistance spring force which is chosen by the user for the user&#39;s body work out. 
     It is a further object of the present invention to provide an additional “U” shaped electrically contacting member comprising a bottom electrically conducting arm which is used to embrace a transverse top member of the “U” shaped force selection member, so that the bottom electrically conducting arm of the “U” shaped electrically contacting member will provide a better electrical contact to two electrodes of the electronic light or sound indicator for securely generating the alarm so that the user will be securely informed that his muscle outputs a force which reaches a level of the&#39;desired isometric resistance spring force which is chosen for the user&#39;s exercise. 
     Further novel features and other objects of the present invention will become apparent from the following detailed description, discussion and the appended claims, taken in conjunction with the drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Referring particularly to the drawings for the purpose of illustration only and not limitation, there is illustrated: 
         FIG. 1  is a perspective view of the present invention portable isometric exercise device to illustrate components of the device, including a body of the device incorporated with an electronic light or sound indicator, a first and second upper grip linked with a cable or string, and a lower grip, wherein the cable or string and lower grip are separately incorporated within the device body; 
         FIG. 2  is a cross-sectional view of the two halves of the device to illustrate the major parts installed inside of the device body including a coil resistance force spring inside incorporated with a “U” shaped spring force selection member, a pulley, and an isometric spring force selector; 
         FIG. 3  is a perspective exploded view of the present invention to illustrate the coil resistance force spring inside incorporated with the“U” shaped force selection member, isometric spring force selector, first and second upper grip which are connected to a cable or string, lower grip, and bottom cover incorporated with a pulley which links the cable or string; 
         FIG. 4  is a perspective view with a partial cut away view of the electronic light or/and sound indicator; 
         FIG. 5A  is a cross-sectional view of the device to illustrate how the present invention works through providing a first example where a pair of openings is selected which is at a higher position of the isometric spring force selector by plugging the electronic light or sound indicator into the openings, which higher position corresponds to a lower level of the spring resistance force. The device body is presented for a better illustration wherein the top cover of the device body is removed, the top flat section of the isometric spring force selector is cut away, all unused openings of the isometric spring force selector are in dotted lines as well as the body of the electronic light or sound indicator; and 
         FIG. 5B  is a cross-sectional view of the device to illustrate how the present invention works through providing a second example where a pair of openings is selected which is at a lower position of the isometric spring force selector by plugging the electronic light or sound indicator into the openings, which lower position corresponds to a higher level of the spring resistance force in comparison with the selected higher positioned of the openings illustrated in  FIG. 5A . The device body is presented for a better illustration wherein the top cover of the device body is removed, the top flat section of the isometric spring force selector is cut away, all unused openings of the isometric spring force selector are in dotted lines as well as the body of the electronic light or sound indicator. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Although specific embodiments of the present invention will now be described with reference to the drawings, it should be understood that such embodiments are by way of example only and merely illustrative of but a small number of the many possible specific embodiments which can represent applications of the principles of the present invention. Various changes and modifications obvious to one skilled in the art to which the present invention pertains are deemed to be within the spirit, scope and contemplation of the present invention as further defined in the appended claims. 
     The present invention is a portable isometric exercise device, comprising an elongated isometric spring force selector having multiple paired openings positioned along its longitudinal direction which are proportional to various isometric levels of spring forces of a coil spring compressed by a user in exercise, the coil spring inside is incorporated with a “U” shaped spring force selection member having a top transverse force selection member which is inserted into a middle flat channel with opened sides of the isometric spring force selector and further slidable inside of the channel, and an electronic light or sound indicator comprising an electronic light or sound component which is plugged into two paired openings in a row of the isometric spring force selector. The device will generate an alarm of light or sound from the indicator when the coil spring is compressed by the user to reduce its length which results in a downwardly sliding movement of the top transverse force selection member to electrically contact two electrodes of the indicator. Therefore the user will be aware that his muscle forces reaches a level of the spring forces that he has chosen through choosing the paired openings of the isometric spring force selector for his body work out. 
     Referring to  FIGS. 1 ,  2  and  3 , there are illustrated structural components of the present invention portable isometric exercise device  1 , comprising a first upper grip  10  and a second upper grip  16 , a cable or string  22 , a lower grip  30 , an electronic light or sound indicator  140  and a body  38  of the device which has its upper and lower sections fastened with multiple fasteners such as screws  41 ,  43 ,  47 ,  149  and  151 . 
     The first and second upper grips  10  and  16  are identical as further illustrated in  FIG. 3 . The first upper grip  10  is comprised of a retaining member  12  which at one end is connected to a first end  26  of a cable or string  22 , and at an opposite end is affixed to both ends of a strap  14  to form a loop having a looped end  15 . Similarly, the second upper grip  16  has a retaining member  18  which at one end is connected to the second end  28  of the cable or string  22  and at its opposite end is connected to both ends of strap  20  to form a loop having a looped end  19 . The cable or string  22  is illustrated at its middle portion  24  to slidably retained in an interior channel  106  of a pulley  102  which is installed onto a bottom cover  108  of the device body  38 . Therefore, the cable or string  22  can be rotatably moved along with a rotation of the pulley  102  if the first or second upper grip  10  and  16  is pulled. 
     The exercise device body  38  as illustrated in  FIGS. 1 through 3  comprises a top cover  40  and a bottom cover  108 , an isometric spring force selector  52 , a coil resistance force spring  84  positioned between top cover  40  and bottom cover  108 , and a “U” shaped spring force selection member  90 , extending within the coil resistance force spring  84 . Also included is a separate electronic light or sound indicator  140 . 
     The resistance force spring  84  is an elongated coil having a top end  86  and a bottom end  88 . The majority of the “U” shaped spring force selection member  90  is positioned inside coil force spring  84 . The “U” shaped spring force selection member  90  as illustrated in  FIG. 3  comprises a “U” shaped bottom connecting member  100  connected to a left longitudinal bar  91  terminating in a left top short transverse end  92  and a right longitudinal bar  93  having a transverse right top end  94  which continues to a transverse force selection member  96 . In a preferred embodiment, the force selection member  96  is a short section of the spring rod having a wavy shape. It will be appreciated that the left short transverse top end  92  and the transverse force selection member  96  at the right top end  94  lock the “U” shaped spring force selection member  90  into the coil spring  84  at its top end  86 . 
     As further illustrated in  FIG. 3 , an additional “U” shaped electrical contacting member  98  is used to embrace the transverse force selection member  96 . The electrical contacting member  98  comprises a top horizontal arm  98   a  connected to a connecting portion  98   c  which in turn is connected to a bottom horizontal arm  98   b . Top horizontal arm  98   a  is parallel to bottom horizontal arm  98   b  and are aligned with transverse force selection member  96 . The “U” shaped spring force selection member  90  is installed into to the coil spring  84 , wherein the right and left longitudinal bars  91  and  93  are retained inside of the spring, and the right top end  94  is connected with the transverse force selection member  96  with the left transverse top end  92  and right transverse top end  94  placed on the spring top end  86 . The “U” shaped bottom connecting member  100  extends out of the bottom end  88  of the coil spring  84 . 
     The isometric spring force selector  52  is an elongated rectangular piece having a top end  68  and a bottom end  70 , and a right side  72  and a left side  74 . Referring to  FIG. 3 , the isometric force selector  52  is illustrated in detail to comprise a top flat member  78  and a bottom flat member  80 , which surround a middle flat channel  82  between the top and bottom flat members. The middle channel  82  has an opened left side  82   a , an open bottom end  82   b  and a open top end  82   c . The transverse force selection member  96  and the electrical contacting member  98  are inserted into the channel  82  and further slidably retained within the channel  82 , the transverse force selection member being inserted through the open left side  82   a  of channel  82 . 
     The isometric spring force selector  52  is further comprised of a plurality of paired openings  54   a  and  54   b ,  56   a  and  56   b ,  58   a  and  58   b ,  60   a  and  60   b ,  62   a  and  62   b ,  64   a  and  64   b , and  66   a  and  66   b , which are designed to vertically penetrate through the transverse top and bottom flat members  78  and  80 , wherein allocation of the openings is followed with a pattern of two columns and seven rows. Two paired openings  54   a  and  54   b  in the first row are placed closest to the top end side  68  of the isometric spring force selector  52 . The next two paired openings  56   a  and  56   b  in the second row are placed lower than the openings  54   a  and  54   b  in the first row. Following this order, all fourteen openings are arranged which openings  54   a ,  56   a ,  58   a ,  60   a ,  62   a ,  64   a  and  66   a  are in the left column, and the openings  54   b ,  56   b ,  58   b ,  60   b ,  62   b ,  64   b  and  66   b  are in the right column. In addition, a top and bottom screw hole  49  and  51  are placed adjacent to the respective top and bottom end side  68  and  70  for fastening the isometric spring force selector  52  through using the fasteners such as screws  149  and  151  shown in  FIG. 2 . The top cover  40  is a generally a rectangular shape having respectively a top, bottom, right and left side rim  42 ,  44 ,  46  and  48 , comprising an elongated concave left portion  130  and elongated flat right portion  132  attached with a generally rectangular concave small portion  134 . The top rim  44  is further comprised of a left round portion and a right straight portion. A round concave addition  50  is coaxially attached to the top side of the concave left portion  130 . 
     As illustrated in  FIGS. 1 and 2 , the left curved portion  130  of the top cover  40  functions as a half of a housing for the resistance force spring  84  and incorporated “U” shaped spring force selection member  90 , when the left curved portion  130  is combined with a counterpart of the bottom cover  108 . Therefore, two half round opening  45   a  and  45   b  are arranged on the bottom rim  44  and are symmetrically aligned with the longitudinal axis of the left concave portion  130 , which serve as half of the opening for retaining the respective right and left longitudinal bars  93  and  91 . As further illustrated, the top round addition  50  is used as a part of a housing for the pulley  102 , and the elongated flat right portion  132  is used to partially house the isometric spring force selector  52 . It will be appreciated that the bottom concave small rectangular portion  134  also serves as a half housing for the electronic light or sound indicator  140  which can be placed inside of the housing when the present invention exercise device  1  is not in use. In a preferred embodiment, a “U” shaped opening  135  is cut on the half housing  134  for convenience to house the electronic light and/or sound indicator  140 . 
     The top cover  40  on its inner side  40   b  close to the left rim  46  contains a top and bottom cylindrical post  49   a  and  51   a  having a central female threaded hole to match the respective top and bottom opening  49  and  51  of the isometric spring force selector  52  for fastening the device body  38 . In addition, there are three additional cylindrical posts on the inner side of the top cover  40 , which includes a top one  41   a  and two bottom ones are  43   a  and  47   a  for also for fastening the device body  38 . 
     The top cover  40  is further comprised of a multiplicity of paired openings  154   a  and  154   b ,  156   a  and  156   b ,  158   a  and  158   b ,  160   a  and  160   b ,  162   a  and  162   b ,  164   a  and  164   b , and  166   a  and  166   b , which are placed on the right flat portion  132  of the top cover  40 , as illustrated in  FIG. 2  when viewed from the inner side  40   b  of the top cover. The multiple paired openings are arranged in the same format of two columns and seven rows as the format of the openings on the isometric spring force selector  52 , wherein the paired openings  154   a  and  154   b  in the first row which are closest to the top end side rim  42  match the respective paired openings  54   a  and  54   b  on the isometric spring force selector  52 . Similarly, each opening on the top cover  40  matches the respective opening on the isometric spring force selector  52 . It will be appreciated that the electronic light or sound indicator  140  having two electrodes  150   a  and  150   b  can be plugged into any two paired openings in a row on the isometric spring force selector  52  through the corresponding two paired openings of the top cover  40 . In a preferred embodiment, each round opening  54   a  of the isometric spring force selector  52  has an annular rim  55   a  to surround the opening  54   a  shown in  FIG. 3 , and each round opening  154   a  on the top cover  40  matches the size of the annular rim  55   a . Therefore, the annular rim  55   a  will be placed to extend through the opening  154   a  when the top cover  40  is placed on the top of the isometric spring force selector  52  for assembling the device body  38 . 
     The bottom cover  108  is generally a mirror image of the top cover  40 , which is illustrated through its inner side shown in  FIG. 3 , having a top, bottom, right and left side rim  110 ,  114 ,  116  and  118 . It will be appreciated that each of the bottom cover rims matches the respective rim of the top cover, so that the top and bottom cover  40  and  108  can be perfectly combined together. The bottom cover  108  is illustrated to further comprise an elongated convex left portion  120  and elongated flat right portion  122  attached with a generally rectangular convex small portion  123 . A round convex addition (not shown) is coaxially attached to the top of the elongated convex left portion  120 , wherein a rotation axle  125  is vertically placed at the center of the round convex addition for installation of the pulley  102 .  FIG. 3  also shows a plurality of the screw holes  41   b ,  43   b ,  47   b ,  49   b  and  51   b  on the bottom cover  108 , which matches the respective cylindrical posts  41   a ,  43   a ,  47   a ,  49   a  and  51   a  on the inner side of the top cover  40 . It will be appreciated that as illustrated in  FIGS. 1 to 3 , the left convex portion  120  of the bottom cover  108  provides the other half of the housing for the resistance force spring  84  incorporated with the “U” shaped spring force selection member  90 . Therefore two half round openings  115   a  and  115   b  are arranged on the bottom rim  114  symmetrically along with a longitudinal axis of the left convex portion  120 . Two half round openings  115   a  and  115   b  functioned as a respective opposite half of the respective round opening for retaining the respective left and right longitudinal bars  93  and  91  of the “U” shaped spring force selection member  90 . It will be further appreciated that the top round addition is part of the housing for the pulley  102 , and the bottom convex small rectangular portion  123  with a preferred “U” shaped opening  126  also forms a half of the housing for the electronic light or/and sound indicator  140 , wherein the above mentioned respective housings are completed when the top and bottom cover  40  and  108  are assembled together with the fastener means such as screws  41 ,  43 ,  47 ,  149  and  151  through the respective screw holes  41   b ,  43   b ,  47   b ,  49   b  and  51   b  of the bottom cover  108  to threadedly connect the respective cylindrical posts  41   a ,  43   a ,  47   a ,  49   a  and  51   a  of the top cover  40 . 
     Referring to  FIGS. 1 and 3 , there is illustrated lower grip  30  having a strap comprising a first end  34  and a second end  36 , and a middle section  32 , wherein the first and second ends  34  and  36  of the strap are both looped/chained onto the “U” shaped bottom connecting member  100  of the “U” shaped force selection member  90  to form a loop having a loop end at middle section  32 . 
     The electronic light or sound indicator  19  shown in  FIG. 4  is comprised of a body  142  with an outer cover. Inside of the body is included a disc battery  146  attached onto an integrated electronic device  144  containing an electronic light component such as an LED, or a standard electronic sound component. The integrated electronic device  144  is electrically connected to a first and second electrode  150   a  and  150   b  through a respective first and second wire  148   a  and  148   b . It will be appreciated that the integrated electronic device  144  works in such way so that it is in a standby state when the two electrode  150   a  and  150   b  are electrically open. At the standby state, only finite electric current is needed for the electronic integrated device  144  so that the disc battery  146  can work for a long period of time. Once two electrodes  150   a  and  150   b  are changed to an electrically completed circuit state, the integrated electronic device  144  will be activated so that it drives the electronic light or sound component to produce a visual light signal and/or an audible sound which serves as an indicator. However even in the activated state, only a very limited current is needed for the integrated electronic device  144 , which makes the battery  146  have a long usable life time. 
     The device body  38  is assembled in accordance with the illustration of  FIGS. 1 to 3 . The spring  84  incorporated with the “U” shaped spring force selection member  90  is placed into the housing which is comprised of the concave section  130  of the top cover  40  and convex portion  120  of the bottom cover  108  when the top and bottom covers  40  and  108  are combined together, wherein the top end  86  of the resistance force spring  84  is placed behind but immediately to contact a top inner side of the housing including a part of the top rim  110  and  42  of the respective bottom and top covers  108  and  40 . Similarly the bottom end  88  of the force spring  84  is placed above but immediately to contact a bottom inner side of the housing including a part of the bottom rim  44  and  114  of the respective bottom and top covers  108  and  40 . The bottom “U” shaped connecting member  100  of the “U” shaped force selection member  90  is placed outside of the spring housing of the device body  38  through two openings, of which one is combined with the respective half round openings  45   a  and  115   a  of the respective top and bottom cover  40  and  108 , and the other one is formed from combining the half round openings  45   b  and  115   b . The isometric spring force selector  52  is placed between the flat longitudinal portions  132  and  122  of the respective top and bottom covers  40  and  108 , wherein each opening  54   a  and  54   b  on the isometric spring force selector  52  matches each corresponding opening  154   a  and  154   b  on the top cover  40 , and the transverse force selection member  96  of the “U” shaped force selection member  90  is embraced by the “U” shaped electrical contacting member  98  placed inside of the middle flat channel  82  of the isometric spring force selector  52 . The body  38  of the device  1  is completely assembled after all the fasteners shown in  FIG. 2  are affixed, so that the “U” shaped force selection member  90  is movable along the longitudinal direction of the device body  38 . 
     Referring to  FIGS. 5A and 5B  now, there is illustrated application of the present invention  1  isometric exercise device, wherein both  FIGS. 5A and 5B  are perspective cross-sectional views to show part of the invention  1  including a part of the cable or string  22  and lower grip  30 , wherein the top cover  40  is removed from the device body  38 , and the top flat section  78  of the isometric spring force selector  52  is cut off to better illustrate how the present invention  1  works. 
     When in use, a user first has to choose a spring force level from which the user prefers to exercise his body muscles for an isometric resistance. To do that the user simply needs to remove the electronic light or/sound indicator  140  stored inside of the housing which is formed from combining the small rectangular curved portions  134  and  123  of the respective top and bottom coves  40  and  108 , and insert two electrodes  150   a  and  150   b  of the indicator  140  into two openings in the same row on the isometric spring force selector  52 . For example as illustrated in  FIG. 5A , the user first chooses a lower level of the spring force and inserts two electrodes  150   a  and  150   b  of the indicator  140  into the paired openings  56   a  and  56   b  which are placed at a higher position of the isometric spring force selector  52 . Then the user uses his right and left hand to grip the respective loop ends  15  and  19  of the first and second upper grip  10  and  16 . Meanwhile the user uses his foot to stand on the loop end  32  of the lower grip  30  which is affixed to the bottom end  100  of the “U” shaped force selection member  90 . The user then can start to exercise his body muscles by pulling two upper grips  10  and  16  upward into a higher vertical position, wherein the grips are linked to the cable or string  22  which is connected to the pulley  102 . This results in raising a vertical position of the exercise device body  38  by the user to raising the position of the pulley  102 , so as to raise the vertical position of the bottom rim  44  and  114  of the respective top and bottom cover  40  and  108 . In accordance with these physical conditions, the coil resistance spring  84  inside of the device body  38  is compressed to have a reduced length due to the upward pulling force from the user which is applied to the bottom end  88  of the coil resistance spring  84 , through the bottom side of the coil spring housing including part of the bottom rims  44  and  114  of the respective top and bottom covers  40  and  108 , wherein the physical conditions also require that the bottom end  100  of the “U” shaped force selection member  90  is placed at a fixed position, and the top end  86  of the coil spring  84  is locked by the top short transverse left end  92  and transverse right member  96 . Therefore the transverse force selection member  96  embraced with the “U” shaped electrical contacting member  98  is relatively slid downwardly inside of the middle flat channel  82  of the isometric spring force selector  52 , in accordance with the reduction of the coil spring length. The user will continuously pull the device body  38  upwardly until the bottom arm  98   b  of the electrical contracting member  98  contacts both the first and second electrodes  150   a  and  150   b  of the electronic light or sound indicator  140  which competes the electronic circuit so that a visual or audible signal is generated. At this moment, the integrated electronic device  144  is activated so that it drives the electronic light component to emit a light or the electronic sound component to emit a sound, so that the user is informed from the signal of the light or sound that his muscles are exerting the desired isometric force to reach the level of the spring force which the user has chosen. In accordance with the above illustrated physical conditions, the “U” shaped bottom connecting member  100  of the spring force selection member  90  incorporated with the resistance force spring  84  is at a vertical position “A”, while the bottom end side rim  114  of the device body bottom cover  108  is raised to a position “B”, and the reduction of the spring length is indicated as “H 1 ” in  FIG. 5A . 
     It will be appreciated that in this situation the user can choose to maintain the positions for continuously isometrically exercising the user&#39;s muscles to exert forces to balance the resistance force of the spring so that a continuous visual or audible signal is emitted from the indicator  140  to advise the user that the user is maintaining the desired isometric tension force. If the user lessens his force so that the desired isometric force is not applied by the user, the electrical contacting member  98  moves away form the electrodes  150   a  and  150   b  and thereby breaks the circuit and the visual or audible signal is terminated. The user then knows that the user is not applying the required isometric force to exercise the user&#39;s muscles at the desired level. Therefore, the present invention assures that the user will always maintain the desired isometric force over the desired time and will not inadvertently lessen the force and not receive the full benefit of the isometric exercise. If the force is reduced, then the resistance force spring  84  will expend back to its original position inside of the device body  38 , which results in a corresponding downward movement of the device body  38  including the isometric spring force selector  52 . It will be further appreciated that the downward movement of the isometric spring force selector  38  is equivalent to an upward movement of the “U” shaped spring force selection member  90  including the transverse force selection member  96  embraced with the electrical contacting member  98 . Therefore the electrical contact will be lost on the two electrodes  150   a  and  150   b  which makes them at the electrically open state, so that the integrated electronic device  144  will be returned to its standby state. Therefore, the signal of the light or sound of the electronic device  140  will be terminated immediately as soon as the loss of the electrical contact of two electrode  150   a  and  150   b.    
       FIG. 5B  illustrates another situation wherein the user chooses a higher level of the spring resistance force for the user&#39;s exercise so that the user inserts the indicator  140  into the paired openings  60   a  and  60   b  which are located at a lower position on the isometric spring force selector  52 , in comparison with the higher position of the paired openings  56   a  and  56   b  shown in  FIG. 5A . It will be appreciated that after this selection of the force level, the user will perform the same actions as those illustrated in  FIG. 5A , wherein the exercise device  1  will respond accordingly. The user will get an indication of the signal from either the light or sound which makes the user know that his muscles are generating the required isometric resistance force to balance the greater resistance spring force at the level the user has chosen. In that situation, the “U” shaped bottom end  100  is still at the vertical position “A”, while the bottom side rim  114  of the device body bottom cover  108  is raised to a higher position “B′”, and a reduction of the spring length is indicated as “H 2 ” in  FIG. 5B . The length “H 2 ” is longer than the length “H 1 ” in  FIG. 5A . Therefore, the longer distance “H 2 ” corresponds a larger reduction of the coil spring length, which corresponds to a greater resistance force from the coil spring which needs a greater muscle force to balance it. 
     From the above two examples, it will be appreciated that the present invention  1  brings significant advantages through significant improvement to the conventional coil resistance force spring based exercise devices. The significant advantage as well as improvement of the present invention is to provide a device which the user will have a freedom to precisely choose a level of the force load in the user&#39;s exercise for his particular needs, since the present invention which employs the isometric spring force selector  52  incorporated with the “U” shaped spring force selection member  90  fully applies the principle of the coil resistance force spring wherein the output force of the coil spring is proportional to a change of the spring length. Therefore, the user can quantitatively choose the level of spring force load in his exercise through simply choosing a position of two openings in the same row on the isometric spring force selector  52 . 
     The significant advantage as well as improvement of the present invention is also from providing the electronic light or sound indicator  140  which serves to assist the user to achieve the user&#39;s objective of maintaining a desired isometric pulling force for a given period of time through the indicator providing the signal of the light or sound as the indication that the chosen force level is reached and maintained so that the user can objectively control intensity and total amount of his work out. 
     It will be appreciated that although the above disclosure of the present invention portable isometric exercise device  1  is comprised of the coil spring  84 , it is within the spirit and scope of the present invention to encompass other spring force devices such as an air spring as long as the level of resistance can be adjusted and the signal produced to advise the user that the isometric force is being maintained. 
     It will also be appreciated that the above examples illustrate applications of the present invention portable isometric exercise device  1  wherein the device body  38  is positioned in a vertical orientation. It is within the spirit and scope of the present invention for the device body  38  to be orientated in any direction when the exercise device  1  is used. For example, the device body  38  can be positioned in a horizontal orientation. In accordance with the position, the user can use one hand to grasp both upper grips and another hand to grasp the lower grip, therefore the user can use the present invention portable isometric exercise device  1  to mainly exercise his arm and chest muscles. 
     Defined in detail, the present invention is a portable isometric exercise device, comprising: (a) a body having a top cover and a mating bottom cover which define a generally cylindrical interior chamber in one area and a generally rectangular interior chamber in an adjacent area; (b) a coil resistance spring having a top end and bottom end housed in the cylindrical chamber and retaining a “U” shaped spring force selection member having an arcuate lower section which extends below the bottom end of the coil spring and out of the body and a first longitudinal bar adjacent the top of the coil spring and terminating in a first transverse retaining member and a second longitudinal bar terminating in a transverse force selection member adjacent the top of the coil spring and extending in a direction opposite to the first transverse member; (c) an isometric spring force selector being a generally rectangular structure retained within the generally rectangular chamber of the housing and having an interior slot extending through a longitudinal opening in a wall facing the coil spring, a multiplicity of paired force selection resistance level openings positioned in an aligned column on the spring force selector, the top cover having aligned matching openings; (d) the transverse force selection member partially surrounded by a “U” shaped metal connection member, the force selection member and “U” shaped metal connection member positioned within the slot of the isometric spring force selector so that after the top and bottom covers are joined together, the bottom of the “U” shaped spring force selection member can be pulled to cause the transverse force selection member and “U” shaped metal connection member to be aligned with a given pair of openings; (e) an electronic signal indicator having two metal prongs which extend from a body of the indicator which contains an electronic signal means therein, so that when the two metal prongs are inserted into a respective one of the pair of openings, the prongs come in contact with the “U” shaped metal connection member to close an electric circuit and cause a signal to be continuously emitted and when the “U” shaped metal connection member moves away from the area into which the two metal prongs have been inserted, the signal is terminated; and (f) a first gripping means looped/chained to the arcuate lower section of the “U” shaped spring force selection member and a second gripping means affixed to the body at a location remote from the first gripping means, body parts used to pull the two gripping means apart so that the transverse force selection member and “U” shaped metal connection member come in contact with the selected location where the two metal prongs are located and a continuous signal is emitted to advise that the given level of isometric resistance force is achieved and maintained and if the force is reduced, the transverse force selection member and “U” shaped metal connection member move away from the prongs and the signal is terminated. 
     Defined more broadly, the present invention is a portable isometric exercise device, comprising: (a) a body having a top cover and a mating bottom cover which define a generally cylindrical interior chamber in one area and an adjacent chamber in an adjacent area; (b) a coil resistance spring having a top end and bottom end housed in the cylindrical chamber and retaining a spring force selection member having an arcuate lower section which extends below the bottom end of the coil spring and out of the body and means to retain the spring force selection member within the coil spring, the spring force selection member having a transverse force selection member adjacent the top of the coil spring and extending in a direction transverse to the length of the coil spring; (c) an isometric spring force selector having a housing retained within the adjacent interior chamber of the body and having an interior slot extending through a longitudinal opening in a wall facing the coil spring, a multiplicity of force selection resistance level openings positioned with at least one opening in a row and the openings positioned in an aligned column on the spring force selector, the top cover having aligned matching openings; (d) the transverse force selection member partially surrounded by a metal connection member, the force selection member and metal connection member positioned within the slot of the isometric spring force selector so that after the top and bottom covers are joined together, the lower arcuate surface of the spring force selection member can be pulled to cause the transverse force selection member and metal connection member to be aligned with a selected opening; (e) an electronic signal indicator having at least one metal prong which extends from a body of the indicator which contains an electronic signal means therein, so that when the at least one metal prong is inserted into a respective one of the aligned openings, the prong comes in contact with the metal connection member to close an electric circuit and cause a signal to be continuously emitted and when the metal connection member moves away from the area into which the at least one metal prong was inserted, the signal is terminated; and (f) a first gripping means looped/chained to the arcuate lower section of the spring force selection member and a second gripping means affixed to the body at a location remote from the first gripping means, body parts used to pull the two gripping means apart so that the transverse force selection member and metal connector come in contact with the selected location where the at least one metal prong is located and a continuous signal is emitted to advise that the given level of isometric resistance force is achieved and maintained and if the force is reduced, the transverse force selection member and metal connector move away from the at least one prong and the signal is terminated. 
     Defined even more broadly, the present invention is a portable isometric exercise device, comprising: (a) a body having a top cover and a mating bottom cover which define a generally cylindrical interior chamber in one area and an adjacent chamber in an adjacent area; (b) a coil resistance spring having a top end and bottom end housed in the cylindrical chamber and retaining a spring force selection member having a lower section which extends below the bottom end of the coil spring and out of the body and means to retain the spring force selection member within the coil spring, the spring force selection member having a transverse force selection member adjacent the top of the coil spring and extending in a direction transverse to the length of the coil spring; (c) an isometric spring force selector retained within the adjacent interior chamber of the body and having means to slidably retain the transverse force selection member, a multiplicity of force selection resistance level openings positioned with at least one opening in a row and the openings positioned in an aligned column on the spring force selector, the top cover having aligned matching openings; (d) the transverse force selection member partially surrounded by a metal connection member, the force selection member and metal connection member slidably positioned within the isometric spring force selector so that after the top and bottom covers are joined together, the lower section of the spring force selection member can be pulled to cause the transverse force selection member and metal connection member to be aligned with a selected opening; (e) an electronic signal indicator having at least one metal prong which extends from a body of the indicator which contains an electronic signal means therein, so that when the at least one metal prong is inserted into a respective one of the aligned openings, the prong comes in contact with the metal connection member to close an electric circuit and cause a signal to be continuously emitted and when the metal connection member moves away from the area into which the at least one metal prong was inserted, the signal is terminated; and (f) a first gripping means affixed to the arcuate lower section of the spring force selection member and a second gripping means looped/chained to the body at a location remote from the first gripping means, body parts used to pull the two gripping means apart so that the transverse force selection member and metal connector come in contact with the selected location where the at least one metal prong is located and a continuous signal is emitted to advise that the given level of isometric resistance force is achieved and maintained and if the force is reduced, the transverse force selection member and metal connector move away from the at least one prong and the signal is terminated. 
     Defined most broadly, the present invention is a portable isometric exercise device, comprising: (a) a body having a top cover and a mating bottom cover which define a first interior chamber in one area and a second adjacent chamber in an adjacent area; (b) a coil resistance force means having a top end and bottom end housed in the first interior chamber and retaining a force selection member having a lower section which extends below the bottom end of the resistance force means and out of the body and means to retain the force selection member within the resistance force means, the force selection member having a transverse force selection member adjacent the top of the resistance force means and extending in a direction transverse to the length of the resistance force means; (c) an isometric force selector retained within the second adjacent interior chamber of the body and having means to slidably retain the transverse force selection member, a multiplicity of force selection resistance level openings positioned with at least one opening in a row and the openings positioned in an aligned column on the force selector, the top cover having aligned matching openings; (d) the transverse force selection member partially surrounded by an electrical connection member, the force selection member and electrical connection member slidably positioned within the isometric force selector so that after the top and bottom covers are joined together, the lower section of the force selection member can be pulled to cause the transverse force selection member and electrical connection member to be aligned with a selected opening; (e) an electronic signal indicator having at least one electrical connector which extends from a body of the indicator which contains an electronic signal means therein, so that when the at least one electrical connector is inserted into a respective one of the aligned openings, the electrical connector comes in contact with the electrical connection member to close an electric circuit and cause a signal to be continuously emitted and when the electrical connection member moves away from the area into which the at least one electrical connector was inserted, the signal is terminated; and (f) a first gripping means looped/chained to the lower section of the force selection member and a second gripping means affixed to the body at a location remote from the first gripping means, body parts used to pull the two gripping means apart so that the transverse force selection member and electrical connection member come in contact with the selected location where the at least one electrical connector is located and a continuous signal is emitted to advise that the given level of isometric resistance force is achieved and maintained and if the force is reduced, the transverse force selection member and electrical connection member move away from the at least one electrical connector and the signal is terminated. 
     Of course the present invention is not intended to be restricted to any particular form or arrangement, or any specific embodiment, or any specific use, disclosed herein, since the same may be modified in various particulars or relations without departing from the spirit or scope of the claimed invention hereinabove shown and described of which the apparatus or method shown is intended only for illustration and disclosure of an operative embodiment and not to show all of the various forms or modifications in which this invention might be embodied or operated.