Patent Publication Number: US-2016236032-A1

Title: Stowable lower body fitness apparatus providing enhanced muscle engagement, body stability and range of motion

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 62/060,556, filed Oct. 6, 2014. This application is also related to co-pending applications which also claim benefit of the above-named provisional application, the co-pending applications having the docket numbers KAMINS-002 and KAMINS-004, filed on behalf of the same inventor: Paul Kamins. 
    
    
     FIELD 
     This invention relates generally to fitness equipment, and more particularly to lower body fitness equipment. 
     BACKGROUND 
     In addition to being an integral part of an individual&#39;s overall fitness, toned and shapely buttocks and legs have also become desirable due to their perceived physical attractiveness. As a result, the market for lower body exercise machines and devices has grown in recent years, especially among women. Many such machines and devices are known in the art. 
     One class of exercise machine for the buttocks involves a resistance-transmitting line, such as a weight machine cable, coupled at a pullable end with a user&#39;s leg. Lower body fitness machines that are designed as cable machines can continuously transmit resistance during extension and/or abduction of the user&#39;s hip, which in turn can work the gluteal muscles and enhance sculpting of the buttocks. 
     But such machines can pose problems. In particular, it can be difficult for the user of a machine to fully engage all of their gluteal muscles. Furthermore, attempts to do so can compromise their posture, potentially leading to discomfort or even injury. Meanwhile, many fitness enthusiasts desire to exercise their buttocks at home, but they may prefer not to have to purchase expensive, bulky machinery for this purpose. 
     SUMMARY 
     Various embodiments of an improved stowable lower body fitness apparatus are disclosed, which provide enhanced gluteal muscle engagement, body stability and range of motion. Unlike other known machines for lower body exercise, the present invention safely and efficiently provides maximal engagement of all gluteal muscles, sparing the user from undue discomfort and/or wasted effort in the process. 
     The improved performance of the present invention is facilitated by the strategic placement of a compact cable-swiveling assembly that enables a resistance-transmitting line to swivel about a vertical swivel axis. A gripping device is positioned relative to the swivel axis to allow for effective and even exercise of the entire buttocks, along with increased range of motion and continuous proper stability and body alignment. 
     By positioning the grip locus relative to the swivel axis in accordance with embodiments disclosed below, a new unanticipated synergistic effect is created which leads to optimal gluteal muscle exercise. From a single stance, the user can perform the full range of any combination of hip extension and/or hip abduction under resistance with either leg, easily switching from side to side, all while constantly stabilizing themselves in a balanced tripod posture. 
     Furthermore, the frame of this apparatus is capable of folding down into a state that is substantially parallel with and adjacent to the base, such that the apparatus can be stowed away to avoid wasting space when it is not in use. This enables home users to exercise their gluteal muscles with the highest efficiency possible, but without the need for large and costly equipment continuously taking up room in their home. 
     In one general aspect, the invention is a stowable lower body fitness apparatus, comprising: a base; a frame coupled to and supported by the base, the frame being capable of collapsing into a stowable position that is substantially adjacent to and substantially parallel with the base; a cable-swiveling assembly coupled with the base, the cable-swiveling assembly being configured to engage with a resistance-transmitting cable, to enable a pullable end of the cable to swivel about a vertical swivel axis to allow a user to pull the pullable end with an exercising leg to perform any combination of hip extension and hip abduction from a single standing position; a gripping device connected to the frame, the gripping device including a plurality of grippable areas positioned along a substantially horizontal grip locus, the grip locus being sufficiently positioned relative to the swivel axis to allow the user to stabilize themselves in a tripod posture formed by both arms and a standing leg during the any combination of hip extension and hip abduction; and a leaning space passing through the swivel axis, the leaning space having sufficient volume to allow the user to lean their upper body to achieve full range of exercise motion during the any combination of hip extension and hip abduction. 
     In some embodiments, the cable-swiveling assembly and the frame are configured to enable a user to pull the pullable end of the cable with an exercising leg to perform hip flexion. In some embodiments, the apparatus further comprises a resistance adjustment system. In some embodiments, the cable-swiveling assembly includes a swiveling pulley coupled with the resistance-transmitting cable, the swiveling pulley being free to swivel about the swivel axis. 
     In some embodiments, the apparatus further comprises an intermediate guiding pulley positioned no higher than substantially hip height. In some embodiments, the apparatus further comprises a resistance-activating pulley assembly coupled with the frame, the resistance-activating pulley assembly being configured to engage with the resistance-transmitting cable to facilitate activation of a resistance-generating element. 
     In some embodiments, resistance transmitted by the resistance-transmitting cable is generated by lifting of an exercise weight that is connected to a resistance-bearing end of the resistance-transmitting cable. In some embodiments, the resistance transmitted by the resistance-transmitting cable is generated by stretching of an elastic resistance band that is connected to a resistance-bearing end of the resistance-transmitting cable. 
     In some embodiments, the resistance transmitted by the resistance-transmitting cable is generated by bending of a flexible resistance rod that is connected to a resistance-bearing end of the resistance-transmitting cable. In some embodiments, the resistance transmitted by the resistance-transmitting cable is generated by twisting of a torsional resistance disc that is connected to a resistance-bearing end of the resistance-transmitting cable. 
     In some embodiments, the pullable end of the resistance-transmitting cable is connected to a lower extremity receiving device, the lower extremity receiving device being configured to receive the user&#39;s lower extremity and thereby engage with the user&#39;s leg. 
     In some embodiments, the gripping device is configured to support a user during hip adduction. In some embodiments, the gripping device includes a straight bar positioned along a horizontal grip axis. In some embodiments, the gripping device includes a plurality of handlebars positioned along the grip locus. In some embodiments, the gripping device includes two grippable areas positioned substantially at least shoulders width apart along the grip locus. 
     In some embodiments, the grip locus is substantially at least forearm length from the swivel axis. In some embodiments, the gripping device is height-adjustable. In some embodiments, the apparatus further comprises a swivel-grip displacement adjustment system, the swivel-grip adjustment system being configured to enable adjustment of displacement between the swivel axis and the grip locus. 
     In another general aspect, the invention is a stowable lower body fitness apparatus, comprising: a base; a frame coupled to and supported by the base, the frame being capable of collapsing into a stowable position that is substantially parallel with and adjacent to the base; a swiveling pulley coupled with the base, the swiveling pulley being configured to engage with a resistance-transmitting cable, to enable a pullable end of the cable to swivel about a vertical swivel axis to allow a user to pull the pullable end with an exercising leg to perform full range of motion for any combination of hip extension and hip abduction under resistance from a single standing position that substantially straddles the swivel axis; a weightlifting pulley assembly coupled with the frame, the weightlifting pulley assembly being configured to engage with the cable to facilitate lifting of a liftable exercise weight when the pullable end is pulled with sufficient force; a gripping device connected to the frame, the gripping device including a plurality of grippable areas positioned along a substantially horizontal grip locus, the grip locus being sufficiently positioned relative to the swivel axis to allow the user to stabilize themselves in a tripod posture formed by both arms and a standing leg during the any combination of hip extension and hip abduction; and a leaning space passing through the swivel axis, the leaning space having sufficient volume to allow the user to lean their upper body to achieve full range of exercise motion during the any combination of hip extension and hip abduction. 
     In another general aspect, the invention is a stowable lower body fitness apparatus, comprising: a base; a frame coupled to and supported by the base, the frame being capable of collapsing into a stowable position that is substantially parallel with and adjacent to the base; a swiveling pulley coupled with the base, the swiveling pulley being configured to engage with an resistance-transmitting cable, to enable a pullable end of the cable to swivel about a vertical swivel axis to allow a user to pull the pullable end with an exercising leg to perform full range of motion for any combination of hip extension and hip abduction under resistance from a single standing position that substantially straddles the swivel axis; a band-stretching pulley assembly coupled with the frame, the band-stretching pulley assembly being configured to engage with the cable to facilitate stretching of an elastic resistance band when the pullable end is pulled with sufficient force; a gripping device connected to the frame, the gripping device including a plurality of grippable areas positioned along a substantially horizontal grip locus, the grip locus being sufficiently positioned relative to the swivel axis to allow the user to stabilize themselves in a tripod posture formed by both arms and a standing leg during the any combination of hip extension and hip abduction; and a leaning space passing through the swivel axis, the leaning space having sufficient volume to allow the user to lean their upper body to achieve full range of exercise motion during the any combination of hip extension and hip abduction. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will be more fully understood by reference to the detailed description, in conjunction with the following figures, wherein: 
         FIGS. 1-2  introduce an illustrative embodiment and basic functional framework of the invention, specifically: 
         FIG. 1  is a front oblique view of an illustrative embodiment of the use-for-exercise aspect of the present invention; 
         FIG. 2  is a perspective view of a functional framework of the illustrative embodiment; and 
         FIGS. 3-12  introduce exemplary machine embodiments of the invention, specifically: 
         FIG. 3  is a front oblique view of a possible commercial embodiment of the invention with a hinged mono-tube design; 
         FIG. 4  is a profile view of the embodiment of  FIG. 3  being used to fully perform hip flexion; 
         FIG. 5A  depicts a user  500  using the previous embodiment  300  to perform hip extension; 
         FIG. 5B  is a top view of the embodiment of  FIG. 3  being used to perform simultaneous hip extension and abduction; 
         FIG. 5C  is a top view of the embodiment of  FIG. 3  being used to perform hip abduction; 
         FIG. 5D  is a top view of the embodiment of  FIG. 3  being used to perform hip adduction; 
         FIG. 6  is a front oblique view of the embodiment of  FIG. 3  with its frame fully collapsed into a stowable position; 
         FIG. 7  is a front oblique view of an embodiment of the invention with a three legged frame; 
         FIG. 8A  is a front oblique view of the embodiment of  FIG. 7  being used to perform hip extension; 
         FIG. 8B  is a front oblique view of the embodiment of  FIG. 7  being used to perform hip abduction; 
         FIG. 9A  is a front oblique view of the embodiment of  FIG. 7  with its frame being collapsed down into a stowable position; 
         FIG. 9B  is a front oblique view of the embodiment of  FIG. 7  with its frame fully collapsed into the stowable position; 
         FIG. 9C  is a perspective view of the embodiment of  FIG. 7  having been stowed against a wall; 
         FIG. 10A  is a front oblique view of an embodiment of the invention including an elastic band whose length and tension can be adjusted along a telescoping arm; 
         FIG. 10B  is a profile view of the embodiment of  FIG. 10A ; 
         FIG. 10C  is a front oblique view of the embodiment of  FIG. 10A  with its frame fully collapsed into a stowable position; 
         FIG. 11A  is a front oblique view of an embodiment of the invention including a horizontally compounded elastic band whose tension can be adjusted by a hand crank; 
         FIG. 11B  is a rear view of the embodiment of  FIG. 11A ; 
         FIG. 11C  is a front oblique view of the embodiment of  FIG. 11A  with its frame fully collapsed in the stowable position; 
         FIG. 12A  is a front oblique view of an embodiment of the invention that can use the resistance of a general purpose exercise machine; and 
         FIG. 12B  is a front oblique view of the embodiment of  FIG. 12A  with its frame fully collapsed into a stowable position. 
     
    
    
     DETAILED DESCRIPTION 
     The gluteal muscles are often considered the powerhouse of the body and an essential part of the body&#39;s “core,” and as such, they are of central focus in strength training and physical fitness. Toning of the gluteal muscles also holds substantial aesthetic appeal, particularly for female physiques. However, traditional exercises for targeting the gluteal muscles require weightlifting in a variety of difficult and/or uncomfortable postures. 
     Given the growing desire among women to build their gluteal muscles, the demand for more ergonomic exercise equipment that can effectively target this area of the body has increased substantially. While some resistance-transmitting line machines seemingly offer comparatively comfortable gluteal workout routines, their perceived comfort actually comes at the expense of optimal gluteal muscle engagement. 
     The following detailed description corresponds with the accompanying drawings. First, the current inventive concept is explained by reference to a functional framework, and then various possible embodiments are taught and described. Of central importance is the ability of these embodiments to be collapsed into an easily stowable and portable state, by the folding of their frame down to be substantially parallel to and adjacent to their base. 
     Basic Functional Framework 
       FIGS. 1-2  introduce an illustrative embodiment and basic functional framework of the invention, specifically:  FIG. 1  is a front oblique view of an illustrative embodiment of the use-for-exercise aspect of the present invention; and  FIG. 2  is a perspective view of a functional framework of the illustrative embodiment. These diagrammatic illustrations and explanations help lay groundwork for understanding the benefits of use of commercial embodiments taught here. 
     1 
       FIG. 1  is a front oblique view of an illustrative embodiment of the use-for-exercise aspect of the present invention. The embodiment shown  100  includes a base  102 , a frame  104  attached to and supported by the base  102 , a line-swiveling assembly  106  coupled with the base  102 , a gripping device  108  connected to the frame  104 , and a leaning space  110  that allows a user to lean their upper body for full range of exercise motion during any combination of hip extension and hip abduction, while under continuous resistance. 
     Important features of the present invention during use for exercise are highlighted in this graphically illustrative design  100 . The combination of key structural elements and spatial relationships shown here can be rendered in many different possible embodiments. This embodiment  100  is shown mainly for illustrative purposes. It is a simple abstract representation of one of the most basic structurally feasible embodiments that supports a core functional objective of the invention. A “functional framework” for enabling this core objective is explicated further in connection with  FIG. 2 , below. 
     The functional framework is a functional arrangement of key elements which enable a user to achieve full range of motion for any combination of hip extension and hip abduction, all from a single stance. The key elements and their relative position to each other make up the functional framework, which is present in this illustrative embodiment  100  and is analyzed in isolation in  FIG. 2 . The functional framework can be manifest in many different structural designs, of which the embodiments shown, taught and described in relation to  FIGS. 3-12  are but a few possibilities. 
     The single stance from which a user can perform all manner of hip extension and hip abduction exercises is a central stance that substantially straddles the swivel axis  116 . For the purposes of discussion of the present invention, a user can be said to be substantially “straddling” the swivel axis  116  if they are standing with substantially one leg on either side of the swivel axis  116 . From this single stance, any combination of hip extension and hip abduction can be properly performed, with full range of motion of either leg. 
     In this embodiment, the gripping device  108  includes a plurality of grippable areas positioned along a substantially horizontal grip locus  112 , extended here for illustrative purposes. The grip locus  112  is the locus passing through all grippable areas, terminating at the outermost grippable areas. It is shown here as a grip axis, positioned relative to the line-swiveling assembly  106  to allow a user to lean forward during exercise to properly stabilize themselves through any combination of hip extension and hip abduction movements. In other embodiments, the grip locus  112  can be angled or curved instead of a straight axis. 
     The line-swiveling assembly  106  is configured to engage with a resistance-transmitting line  114  to enable a pullable end of the line to swivel about a vertical swivel axis  116 , allowing a user to pull the pullable end with an exercising leg to perform full range of motion for any combination of hip extension and hip abduction under resistance, from a single standing position that substantially straddles the swivel axis  116 . In this embodiment, an inelastic weight-bearing resistance cable is being used. 
     In this embodiment, the line-swiveling assembly  106  comprises a swiveling pulley that is free to swivel about a vertical swivel axis  116 . Here the pulley  106  is attached directly to the base  102 , but can also be attached to the frame  104  or other connecting structure. The line  114  is fed into the swiveling pulley  106  substantially vertically and perpendicular to the initial direction of pulling, which is what enables its pullable end to swivel freely about the swivel axis  116 . 
     The swiveling pulley shown  106  is able to swivel in a full circle about the swivel axis  116 , thereby allowing the pullable end of the line  114  to swivel along a swivel arc  118  about the swivel axis  116 . The unobtrusive pulley  106  guides the pullable end in a swivel arc  118  of considerably tight radius, ensuring that a user can accomplish all hip motions from a single stance that substantially straddles the swivel axis  116 , and under continued resistance through their entire range of motion. 
     From the line-swiveling assembly  106 , the resistance-transmitting line  114  is then guided across the frame  104 . In the embodiment shown, the frame  104  includes a vertical support post  120  attached to the base  102 , and a diagonal boom  122  attached to and supported by the support post  120 . The line  114  is guided along the inside of the boom  122  by a resistance-activating pulley assembly, which in this case is a “weightlifting” pulley assembly comprised of a lower boom pulley  124  and an upper boom pulley  126 , after which the cable  114  then connects to weight  128 . 
     In this embodiment, the resistance-transmitting line  114  is a weight machine cable configured to lift weight  128  in cooperation with a weightlifting pulley assembly  124 ,  126  coupled with the frame  104 . In other embodiments, the line  114  can transmit resistance generated by other means, such as: via the stretching of an elastic band; or by the bending of a resistance rod (also known as a tension rod), for example. Still other resistance-generating elements may occur to one of ordinary skill in the art. 
     The weight  128  can be held steady by a stabilizing cable  130  that runs adjacent to the weightlifting cable&#39;s weighted portion  132  (the portion dropping vertically from the upper boom pulley  126  to the weight  128 ). As shown, the stabilizing cable  130  can be anchored at its top end to the upper end of the diagonal boom  122 , and at its bottom end to the base  102 . This stabilizing cable  130  prevents the weight  128  from swaying off its vertical axis, and thereby becoming destabilized. In designs without the stabilizing cable, the user&#39;s form has to be more precise to prevent sway of the weight suspended freely from the cable. 
     In embodiments where the resistance-transmitting cable  114  transmits resistance that is generated by an elastic resistance band or a flexible resistance rod, the elastic resistance band can provide linear variable resistance, engaging the muscles with greater resistance as the muscle&#39;s own strength capacity increases. This can lead to increased benefits during gluteal exercise. Inclusion of elastic band is taught and described in greater detail below, in connection with  FIGS. 10 and 11 . 
     The swiveling pulley  106  of this embodiment is free to fully rotate in its horizontal plane, and also to tilt in its orientation. It is unobtrusive enough to enable a user to stand in close proximity to and straddle the swivel axis  116 . While not exercising, the user can stand in a single neutral stance with no resistance applied. However, even a small displacement of the exercising leg for hip extension and/or abduction can generate resistance. 
     To emphasize, this versatile swiveling pulley  106  functions as an enhanced line-swiveling assembly, whereby the user is able to perform the full range of any combination of hip extension and hip abduction under continued resistance, while also returning to the same neutral stance at the end of a given set of leg motions. Such convenience is not made available by line-swiveling assemblies typically found in the art of lower body fitness machines. 
     In addition to enabling hip extension and hip abduction, the line-swiveling assembly  106  also can allow for nearly all degrees of flexion for anterior musculature strengthening that goes beyond enhancement of the gluteal muscles. And with every available motion, the neutral standing position itself encounters no resistance, yet a slight displacement in any direction immediately does yield resistance. This feature is optimal for exercise yet not available in conventional gluteal exercise machines. 
     Ease of exercise can be further enhanced by a lower extremity receiving device (hereinafter referred to as “LERD”)  134  attached to the line&#39;s pullable end. In this embodiment, the LERD  134  includes a loop which can receive a user&#39;s foot during exercise. A horizontal opening along a distal portion of the loop can be secured around the user&#39;s heel during hip extension, while the loop in its entirety can wrap around the side of the user&#39;s foot during hip abduction. More highly designed LERDs are described in an accompanying app, and pictured later in this document. 
     Unlike the bulky pulley assembly of many prior art exercise pulleys, the customized pulley  106  of  FIG. 1  can enable the LERD  134  to rest on the floor. The LERD  134  can include structural support that keeps it erect and poised to receive a user&#39;s foot, as shown, so that the user can step in and out with ease. This relieves the user from the need to manually engage or disengage the device with their foot, or to change their foot&#39;s orientation in the device by hand when changing up sets. 
     This illustrative embodiment  100  also includes a boom hinge  138  which enables the distal upper end of the diagonal boom  122  to be folded downwards so the boom collapses adjacent to and parallel with the vertical support post  120 ; as well as a post hinge  140 , which enables the vertical support post  120  to be folded downwards to lie adjacent to and parallel with the base  102 . The hinges  138 ,  140  can be locked into the closed or open state, to securely fasten the frame in the desired state. 
     2 
       FIG. 2  is a perspective view of a functional framework of the illustrative embodiment. The functional framework  200  is an isolated grouping of key elements of the illustrative embodiment, which together are responsible for enabling a core functional objective of the present invention. Specifically, the geometrical alignment, spatial relationship, and relative positioning of these elements enable a user to perform the full range of motion for any combination of hip extension and hip abduction, all while under continuous resistance, from a single standing location and with ideal posture. 
     The line-swiveling assembly  106  in this case is a swiveling pulley. It is configured to engage with the resistance-transmitting line  114  to enable its pullable end to swivel about the swivel axis  116 . The swiveling pulley  106  itself is capable of swiveling in a full swivel circle  202 . However, a user need not cross their leg in front of them to extend or abduct their hip. Therefore, the line  114  itself swivels through a swivel arc (see  FIG. 1 ) that is bounded at the user&#39;s “12-o′-clock” position, where the frame (not shown) itself extends to guide the line  114 . 
     The gripping device  108  includes a plurality of grippable areas positioned along a substantially horizontal grip locus  112 , where the grip locus  112  is positioned relative to the swivel axis  116  in a manner that allows a user to stabilize themselves in a “tripod posture” (formed by both arms and a standing leg) during any combination of hip extension and abduction, even when under considerable exercise resistance. In the embodiment shown, the grip locus  112  is a horizontal grip axis. 
     The grip locus  112  is the locus of points along which all grippable areas lie. It does not actually extend beyond the outermost grippable areas of the gripping device  108 , but as it is depicted and labeled in  FIGS. 1 and 2 , it is shown extending beyond the gripping device  108  solely for illustrative purposes. The grip locus  112  need not be a straight axis; it may be curved or bent. It can take any shape that would enable a user to perform full range of motion for any combination of hip extension and hip abduction with proper form. 
     In this embodiment, the gripping device  108  is a grippable bar positioned along a grip axis  112 . This design enables a user to engage the gripping device  108  in a manner similar to a ballet bar. All hip and other lower body exercises that a ballet dancer might practice with such a bar would also be available to a user of this embodiment, with the extra benefit of added resistance for more intensely engaging gluteal and/or other lower body muscles. 
     The ballet bar  108  is one possible embodiment of the gripping device. In some embodiments, the gripping device may be a curved rail or a bent rail, while in other embodiments it may include a set of horizontal handlebars, or even a set of vertically oriented handles, for example. In each instance, the gripping device  108  is designed and positioned to allow a user to maintain tripod posture all throughout their exercise. 
     As defined herein, the user can be said to be in “tripod posture” if their standing leg adjacent to the swivel pulley and their hands spread sufficiently wide on the grip axis to allow their torso to lean slightly opposite their lifting leg. 
     This positioning requires anterior-posterior separation  136  of the grip locus  112  from the swivel axis  116 , allowing their torso to lean slightly opposite their lifting leg. This positioning requires anterior-posterior separation  336  of the grip locus  312  from the swivel axis  316 , to allow the user&#39;s the three stationary limbs to be widely separated (a theoretical tripod configuration). This confers maximal torso stability to resist the torque of the resistance on the lifting leg. This is an important departure from other machines. 
     The swivel-grip separation  136  is made more clearly visible in  FIG. 2  by reference to a depth dimension indicator  204 , which indicates the spatial relationship between the swiveling pulley  106  and gripping device  108 . During exercise, a user must contribute a pulling force  206  that is equal and opposite to the force of resistance  208 . The forces on either side of the swivel axis  116  must effectively balance, and it is helpful for the user themselves to be balanced about the swivel axis  116 . Since their lower body is posterior to the swivel axis  116 , it can be advantageous for their upper body to be anterior. Similarly, if the lower body moves laterally to one side, the torso can lean slightly to the opposite lateral side as a counterbalance. 
     The key functional aspect of the gripping device  108  which allows the user to maintain tripod posture during any combination of hip extension and hip abduction under exercise resistance is its position relative to the cable-swiveling assembly  106 : the grip locus  112  is set apart  136  from the swivel axis  116 . Decoupling  136  these two element alignments  112 , from  116  provides a far more efficient spatial arrangement for the exercise enthusiast than the prior art under consideration. 
     While on the one hand, the grip  112  must be in front of the user, on the other hand, the swivel  106  needs to be positioned at the user&#39;s feet, so that the force of resistance is perfectly opposite to and in line with the exercising leg&#39;s movement. If the swivel  106  was not placed at the feet but further forward instead, then leg movement during abduction would be complicated by a forward force vector of resistance. This would yield especial difficulty at the beginning of leg movement, when the proportion of the forward vector would be largest. 
     The horizontal displacement  136  of the grip locus  112  from the swivel axis  106  is made possible in part by an intermediate guiding pulley  124 , which in  FIG. 1  was referred to as a “lower boom pulley.” This intermediate guiding pulley  124  occurs in other embodiments shown and discussed herein. This pulley  124  is integral to the functional framework  200 . It enables the swiveling pulley  106  to swivel freely by guiding the cable  114  on an acute angle pathway about the swiveling pulley  106 ; but by also guiding the cable  114  into an obtuse angle about itself  124 , it prevents the cable  114  from obstructing the leaning space  110 . 
     The intermediate guiding pulley as shown  124  is strategic in its position, being located above the line-swiveling assembly, but no higher than substantially the hip height of a user. But the intermediate guiding pulley  124  need not be located above the swiveling pulley  106  in order to accomplish its key functional objective. For example, in functional frameworks of alternative embodiments, it is possible for an intermediate guiding pulley to be located below the swiveling pulley  106 , such as in the instance of a base thick enough to house a pulley. Such a pulley would still guide the line  114  on a right angle path about the swiveling pulley  106 , but in that case, the line  114  would be directed downward, instead of upward (as shown here). 
     The intermediate guiding pulley  124  positioned at or below the user&#39;s hip height is a key feature of the functional framework  200  that sets it apart from much of the prior art. For example, in known machine embodiments (common cable machine) where a user stands near a swiveling pulley, the design does not introduce an intermediate guiding pulley  124  at or below hip height, because such designs do not prioritize the goal of providing a user with optimal gluteal muscle targeting. Instead, they include a guiding pulley that is fixed at the top of a long vertical track, which enables the swiveling pulley itself to slide up or down the vertical track and be repositioned at will, depending on the desired exercise (ranging anywhere from shoulder to arm to leg exercise). 
     In the embodiment shown, the grip locus  112  is substantially at least forearm length  136  from the swivel axis  116 , thereby enabling strong tripod posture. In other embodiments, the grip locus  112  can be closer to the swivel axis  116 , such as hand length, for example. Also, in some preferred embodiments, the gripping device  108  can be substantially at least hip height above the floor and/or its grippable areas span substantially at least shoulders width, as is the case in  FIG. 2 . 
     The grip locus  112  must span the proper width. The grip locus  112  is defined herein as the locus of points along which all grippable areas lie, and as such, it does not actually extend beyond the outermost grippable areas of the gripping device  108 . To be sure, the grip locus  112  as depicted and labeled in  FIGS. 1 and 2  is shown extending beyond the gripping device  108  for illustrative purposes; however, the true grip locus  112  is coextensive with the gripping device  108 , and it terminates where the gripping device  108  itself terminates. 
     Proper positioning and extension of the grip locus  112  requires that its extent be wide enough to allow a user to properly perform full range of motion during hip extension and/or abduction. Therefore, in addition to the gripping device  108  being separated from the swivel axis  116 , the span of the gripping device  108  must extend away from the swivel axis  116  far enough in both directions as to enable a user to comfortably and effectively stabilize themselves throughout the full motion of these hip exercises. Abduction requires even more width of the grip axis. 
     Part and parcel to the benefit conferred by the swivel-grip separation  136  is the presence of the leaning space  110  that allows a user to lean their upper body forward and take full advantage of the swivel-grip separation  136 , as well as the enhanced stability it affords. As the user lifts their exercising leg, it is natural for the user to wish to lean forward to help them balance their lower body&#39;s movement with a counter-force from their upper body. When the user leans forward, the pelvis tilts forward, and increases the available range of hip range of motion by 200%, allowing more gluteal work with each set. This ideal posture is made possible by the synergistic effect of the combination of the leaning space  110  and swivel-grip separation  136 . 
     Due to the harmony of these relationships, a user is able to comfortably perform any combination of hip extension and abduction from a central standing position that substantially straddles the swivel axis  116 . The strategically small swiveling pulley  106 , with its tight swivel radius, provides the clearance to enable the user to stand in this central position. By straddling the swivel axis  116 , the user is able to overcome the tension of the line  114  with a perfectly opposing force from their exercising leg, as well as deftly balance their upper body by leaning in the direction perfectly opposite their exercising leg. 
     Such a precise counterpoise of force vectors, with no tangential forces disrupting any of the user&#39;s exercise movements, is only possible when the user avails themselves of this special “swivel straddle” stance. If the user were not straddling the swivel axis  116 , they would experience at least some orthogonal force vector disturbing the arc of their leg&#39;s movement, and/or they would be compelled to supply at least some twisting and/or torsion of their body to maintain balance. Furthermore, they would have to shuffle their feet to change direction of leg movement and/or to abduct their opposite leg. 
     All benefits of the swivel straddle stance converge on a common theme: unparalleled efficiency in isolating one&#39;s gluteal musculature. From this stance, a user is able to lean into tripod posture and focus the full force of resistance  208  on their gluteal muscles without having to apply torque from any part of their body. The stance also relieves the user of the need to reposition their footing or change their body&#39;s orientation for different leg motions, or when switching their exercising leg. And when the user returns their leg to the upright standing position between sets, the line  114  returns to its neutral resting state: thus, freed from any persistent force of resistance  208 , their leg can also come to rest. 
     By enabling this swivel straddle stance, the swivel-grip separation  136  and leaning space  110  work naturally together to promote the user&#39;s best posture during gluteal exercise. This enables the user to exercise their gluteal muscles in an efficient and comfortable manner, making the process safer, healthier and more enjoyable. It also promotes superior gluteal muscle building due not only to a greater range of motion, but also to a greater strength capacity of the body when exercising in its normal, healthy and anatomically preferable bearing. 
     The embodiment shown offers superior gluteal muscle targeting by enabling a user to execute various leg motions that simultaneously comprise both partial hip extension and partial hip abduction. As just one example, studies indicate that a 45 degree lateral leg movement comprised of half hip extension, half hip abduction, which works the gluteus maximus along the orientation of its fibers, yields optimal results. 
     This embodiment and other embodiments discussed below can also enable a user to perform hip rotation, adduction, and even flexion, enhancing their lower body workout even further. In addition to allowing more leg movement options with better form, it also allows for change in the trajectory and/or orientation of the leg within a given repetition, even enabling such movements as kicks or sweeps. All this can be achieved from a single convenient standing position. 
     Exemplary Machine Embodiments 
       FIGS. 3-12  show exemplary machine embodiments of the invention and its central collapsible and stowable functionalities, specifically:  FIGS. 3-6  include views of a streamlined design embodiment, its use and collapsibility;  FIGS. 7-9  include views of a three-legged embodiment, its use and collapsibility;  FIGS. 10-11  include views of embodiments incorporating an elastic band, their use and collapsibility, and  FIG. 12  shows views of an embodiment that cooperates with a general purpose machine. 
     3 
       FIG. 3  is a front oblique view of a possible commercial embodiment of the invention with a hinged, mon-tube design. This embodiment  300  is unique in providing a design that is both robust and streamlined. The embodiment  300  includes a base  302 , a frame  304  attached to and supported by the base  302 , a line-swiveling assembly  306  coupled with the base  302 , a gripping device  308  connected to the frame  304 , and a leaning space  310  that allows a user to lean their upper body for full range of hip extension and/or abduction. 
     While certain elements shown here (such as the frame  304 , for example) are unique to this embodiment  300 , the same functional framework of  FIG. 2  is present, and achieving the same benefits here as previously discussed. The structural variations of this embodiment  300  therefore do not depart from the essence of the inventive concept. Instead, those variations commingle with and enhance the effectiveness of the functional framework, thereby asserting and demonstrating its value even more clearly. 
     In this embodiment  300  the line-swiveling assembly  306  is a swiveling pulley configured to engage with a resistance-transmitting line  312  to enable a pullable end of the cable  312  to swivel about a vertical swivel axis, thereby allowing a user to pull the pullable end with an exercising leg (via the lower extremity receiving device  314  or “LERD”), to perform full range of motion for any combination of hip extension and hip abduction under resistance, from a single standing position that substantially straddles the swivel axis of the line-swiveling assembly  306 . Here, a weight machine cable  312  is being used as a resistance-transmitting line. 
     From the line-swiveling assembly  306 , the line  312  is guided across the frame  304  along a pathway laid out by a series of pulleys, discussed below. The frame  304  itself includes two angled segments supported and locked into their use-ready relative positions by an elbow buttress hinge  316 . The elbow buttress hinge  316  holds together a diagonal boom  318 , and a lower support post  320  to which the boom  318  is hingedly connected. The lower support post  320  is in turn supported by a base buttress hinge  322 , and hingedly connected to a baseplate  324  attached to the base  302 . 
     The gripping device  308  is mounted to the diagonal boom  318  via a gripping mount  326  which, in this embodiment, includes adjustment features. The gripping mount  326  includes a grip-elevation adjustment mechanism  328 , which enables the mount to be positioned at any elevation along the diagonal boom  318  via loosening and retightening of a knurled knob. Adjusting the elevation of the gripping mount  330  along the diagonal boom  318  effectively adjusts the position of the gripping device  308  relative to the user. 
     The gripping mount  326  also includes a grip-depth adjustment mechanism  330 , which adjusts the position of the gripping device relative to the axis of the diagonal boom. In this embodiment, the gripping device  308  is positioned opposite the diagonal boom  318  from the user&#39;s perspective. The gripping device  308  can be adjusted closer or farther from the diagonal boom  318 , by loosening and retightening a knurled knob against a slidable adjustment fork. Grip depth adjustment can be useful for positioning the gripping device  308  for hip flexion exercise, for example. 
     To position the gripping device  308  in front of the diagonal boom  318  from the user perspective, the slidable adjustment fork  330  can be fully removed from its sleeve, then inserted back into the sleeve from the opposite (user) side of the boom. Both the grip-elevation adjustment mechanism  328  and the grip-depth adjustment mechanism  330  that are located on the gripping mount  326  combine to yield a comprehensive swivel-grip displacement adjustment system, providing the user substantial control over the position of the gripping device  308  including its position relative to the swivel axis, and thus relative to the user. 
     The line  312  is a weightlifting cable configured to lift weight when pulled with sufficient force. The weightlifting cable  312  is guided across the frame  304  via pulleys. First, it is guided vertically upward from the swiveling pulley  306  to a strategically placed elbow pulley  332  inside the elbow of the frame  304 , acting as an intermediate guiding pulley  332 . It is then guided along the inside of the diagonal boom  318 , where it then encounters a boom pulley  334  at the top of the boom  318 . The elbow pulley  332  and boom pulley  334  function together as a weightlifting pulley assembly. 
     A stabilizing cable  336  drops down from the top edge of the diagonal boom  318 , running adjacent to the weightlifting cable&#39;s weighted portion  338 . The weightlifting cable  312  itself drops vertically down from the boom pulley  334 , connecting at its weighted end to liftable weight  340 . The stabilizing cable  336  is connected at its top end to the boom  318  and at its bottom end to the base  302 , and is held taut between those anchor points to keep the liftable weight  340  from swinging. The liftable weight  340  rests on the weight base  302  when it is not being lifted. 
     The embodiment shown  300  achieves a robust but streamlined design. With a frame  304  that is strong but minimal in its mass, this embodiment  300  can function as a weight machine in a home setting, and may be erected and collapsed at will for easy transport, storage and/or setup and use. Such a system of buttress hinges  316 ,  322  as shown here allows for collapsing of the frame  304  down to a stowable state that is substantially adjacent with and parallel to the base  302 . 
     4 
       FIG. 4  is a profile view of the embodiment of  FIG. 3  being used to fully perform hip flexion. Relative to gluteal development, flexion exercise capability is different focus, yet an added bonus. The narrow width of the frame  304  from the perspective of a user  400  facilitates the performance of any desired hip flexion exercises, as shown. Given that no frame elements extend outside of the narrow profile that is occupied by the lower support post  320  and the diagonal boom  318 , a user&#39;s exercising leg can be flexed directly outward and upward, encountering no obstructions along the way. 
     In this figure, a user  400  is using the embodiment of  FIG. 3  to perform hip flexion. This exercise can be used to target lower body muscles other than the gluteal muscles, such as the iliopsoas, rectus femoris, and tensor fascia latae, as well as the abdominal muscles. The user  400  may wish to raise their exercising leg straight in front of them. The narrow profile of the frame, and the height-adjustable grip, make the full range of such straight hip flexion motion possible. The thin width of the central components of the frame  318 ,  320  allows for full and unimpeded flexion of the hip-flexing leg. 
     As shown here, the user  400  can flex their hip under resistance from the line  312  by putting the front of their foot through the socket of the LERD  314 . Hip flexion can also be performed swiftly for practicing front kicks under force of resistance. This profile view illustrates the value of extending the height of the gripping device  308 , which can be achieved by sliding the gripping mount  326  upwards along the diagonal boom  318 . Due to the relative weakness of flexor muscles, the weight  340  can incrementally be calibrated down as appropriate. 
     The integral value of the central swivel straddle stance is apparent when considering the hip flexion exercise shown. As is the case with hip abduction, for example, hip flexion also can be considerably compromised by force vectors orthogonal to the direction of motion of the exercising leg. If the user  400  were not straddling the swivel axis during hip flexion, then the direction in which they pull the line  312  would not be directly away from the swiveling pulley  306 , and there would be a component vector of force that urges the user&#39;s exercising leg off course. 
     However, as depicted in  FIG. 4 , the user  400  is able to straddle the swivel axis due to the low profile design of the swiveling pulley  306  and the frame itself. While in this swivel straddle stance, the user  400  is able to sweep their leg forward with perfect form. The user  400  can also just as easily perform any desired combination of hip flexion and abduction, adding as much lateral movement to their exercising leg as they wish. In that sense, flexion extends the continuum of hip exercises that are allowed by the functional framework, to those anterior to abduction. Still no distracting force vectors will result, thanks once again to the unobtrusive design elements  318 ,  320  that enable continuous swivel straddle stance. 
     5 
       FIG. 5  is a top view of the embodiment of  FIG. 3  being used to perform a wide spectrum of angular hip exercises. However, this same set of exercises can apply to all embodiments.  FIG. 5A  depicts a user  500  using the previous embodiment  300  to perform hip extension. As discussed above, hip extension is a relatively effective exercise for engaging the gluteus maximus, which is the largest gluteal muscle. It is readily apparent from this view that the user  500  benefits from being able to lean over the swiveling pulley and the gripping device  308  to facilitate maximum extension of their exercising leg  502 . 
     An effective tripod posture can only be achieved if the user stands back from the gripping device. If the line-swiveling assembly ( 306 , obscured in  FIG. 5A ) was not set apart from the grip axis  308 , as it is here, then the user  500  would not be able to come to rest by bringing their exercising leg back to the standing position. Instead, the exercising leg  502  would have to be advanced farther forward than the standing leg to meet the cable-swiveling assembly  308 , before returning to a truly neutral position. By contrast, the swivel straddle stance shown allows for “resting neutral.” 
       FIG. 5B  is a top view of the embodiment of  FIG. 3  being used to perform simultaneous hip extension and abduction, specifically: half extension, half abduction. The hip has been rotated externally, and the exercising leg  502  brought 45 degrees laterally from the Sagittal plane. Because this movement follows the orientation of the gluteus maximus fibers (and thereby also avoids contraction of the hamstrings), it completely engages the gluteus maximus: even more so than with pure hip extension. 
     Hip rotation is made possible by the customized lower extremity device (LERD), described in greater detail above. External (or lateral) rotation of the hip during leg motions that involve some hip abduction activates the gluteus maximus more so than without rotation of the hip. The leg movement shown here is extremely effective in gluteal muscle exercise: in addition to fully engaging the gluteus maximus, the partial hip abduction also strongly engages the gluteus medius and minimus muscles. As discussed above, in contrast to the many other known machines, here the grip locus is offset from the swivel axis, enabling the user to lean forward to easily execute full range of motion and yielding far superior muscle activation. 
     This unique leg movement (called “the 45°” due to the angle of the trajectory of the exercising leg relative to the Sagittal plane) is the best combination of hip extension and hip abduction for maximally engaging the gluteus maximus, and is also of central importance in effectively engaging all gluteal muscles in general—especially when combined with external hip rotation, as shown. But in the absence of the displacement of the line-swiveling assembly  306  from the gripping device  308 , this key exercise would not be achievable with proper form. 
     If the swivel axis of the line-swiveling assembly  306  was not set apart from the grip axis of the grip bar  308 , the user  500  would be compelled to shift their standing position laterally, so that the cable&#39;s pathway from the cable-swiveling assembly  306  to the user&#39;s foot was in line with the movement of their exercising leg  502 . Otherwise, leg movement would be compromised and distracted by a forward-component to the force vector of resistance. Furthermore, the user  500  would not be able to come to rest at the end of each repetition, for the same reason as noted above in connection with  FIG. 5A . 
       FIG. 5C  is a top view of the embodiment of  FIG. 3  being used to perform hip abduction. Since hip abduction heavily engages the gluteus medius and minimus muscles, it is essential to a well-balanced treatment of gluteal muscle exercise. Proper form requires a wide grip, as shown. Moreover, separation of the grip locus from the swivel axis is absolutely essential for enabling the user to fully abduct their hip. 
     Straight hip abduction presents a classic case of the need for a stable tripod posture in achieving maximal gluteal muscle engagement. Without the user&#39;s arms functioning as widely spaced levers, allowing the upper torso to lean slightly away from the torque of the resisted lifting leg, the back might be strained, and form and range of motion would surely be compromised. 
     Tripod posture is indispensible to proper hip abduction, yet would not be possible without displacement of the swivel axis from the grip axis. On the other hand, with the swiveling pulley  306  displaced from the vertical plane of the gripping device  308  as in the present invention, the user  500  can fully abduct their exercising leg  502  with proper tripod posture, stabilizing themselves with their arms instead of their lower back. The customized LERD enables the user to perform hip abduction effectively, without any discomfort to the foot. 
     Finally,  FIG. 5D  is a top view of the embodiment of  FIG. 3  being used to perform hip adduction. This exercise actually can be used to better target the lowest portion of the gluteus maximus. Because a user  500  must stand to the side of the swivel axis when adducting the hip, in order to keep their exercising leg&#39;s  502  motion in line with the line&#39;s pathway, a gripping device  1108  of substantial width is advisable, to allow for tripod posture throughout. 
     When considering this motion, once again the advantage of a horizontal displacement between the gripping device  308  and the swiveling pulley  306  is clear. The user  500  is able to rest their exercising leg  502  before and/or after each repetition of the hip adduction movement. This is due to the fact that the pullable end of the resistance-transmitting line is returned to the position of the swiveling pulley  306  once the exercising leg  502  returns to the standing position. In this neutral state (“resting neutral”), no resistance is activated. 
     It should also be noted that each of the exercises shown (as well as still other exercises, such as hip flexion) can be achieved with perfect form from a single standing position that substantially straddles the swivel axis, with continual resistance applied during the entire duration of the exercise, and resistance is inactive upon cessation of the exercise. This convenience greatly enhances the qualitative experience of gluteal exercise and muscle development. 
     The critical importance of the highly versatile central “swivel straddle” stance, in enabling proper form for all manner of gluteal exercise with a resistance-transmitting line, is immediately apparent in  FIG. 5 , and most specifically,  FIGS. 5B and 5C . There, the user  500  is clearly able to perform any combination of hip extension and abduction without any distracting tangential force vectors compelling their exercising leg  502  to veer off its intended course. As noted above, this is also the case for any combination of hip abduction and hip flexion (see  FIG. 4 ) attempted. 
     To be sure, the swivel straddle stance may seem less important during straight hip extension (see  FIG. 5A ). Extension motions conceivably could be executed even if the swiveling pulley  306  were directly below the gripping device  308 , with the user  500  out of swivel straddle stance. But even in this narrow instance, the direction and intensity of the force of resistance is more likely to be discontinuous and disrupted if the user  300  is not straddling the swivel axis. 
     Nonetheless, the overwhelming majority of possible leg motions for well-rounded gluteal exercise with a cable involve at least some degree of (if not substantial) hip abduction. In all such cases, exercise is greatly compromised if the user  500  does not assume swivel straddle stance. This stance exclusively allows the user  500  to perform a wide variety of hip extension and hip abduction combinations with either leg, in full and proper form, without changing position. 
     6 
       FIG. 6  is a front oblique view of the embodiment of  FIG. 3  with its frame fully collapsed into a stowable position. The lower support post  320  has been folded down to be substantially adjacent to and parallel with the base  302 . It has been released from its locked position within the base buttress hinge  322  so that it may move freely into this collapsed position. Likewise, the diagonal boom  318  has been released from its position in the elbow buttress hinge  322  and folded down against the lower support post  320 . 
     The gripping mount  326  can be moved upward along the diagonal boom  318  so that the gripping device  308  is clear of the base buttress hinge  322 . This enables the diagonal boom  318  to fold down fully against the lower support post  320 . In this collapsed configuration, the entire embodiment is now in an easily stowable position. For example, it could be stowed in a closet, under a table or potentially even a bed. 
     7 
       FIG. 7  is a front oblique view of an embodiment of the invention with a three legged frame. The embodiment  700  shares many structural features of the previous embodiment  300  such as its base, swiveling pulley, adjustable gripping device, and some aspects of its frame. However, this frame is unique in its three-legged tripod weightlifting frame design. This design is particularly lightweight, and again is quite easily collapsible and transportable. 
     While certain elements shown here (such as the frame, for example) are unique to this embodiment  700 , the same functional framework of  FIG. 2  is present, and achieving the same benefits here as previously discussed. The structural variations of this embodiment  700  therefore do not depart from the essence of the inventive concept. Instead, those variations commingle with and enhance the effectiveness of the functional framework, thereby asserting and demonstrating its value even more clearly. 
     The embodiment shown  700  includes a base  702 , a tripod frame  704  hingedly attached to and supported by the base  702 , a line-swiveling assembly  706  coupled with the base  702 , a gripping device  708  connected to the frame  704 , and a leaning space  710  that allows a user to lean their upper body for full range of exercise motion during any combination of hip extension and hip abduction, while under continuous resistance. 
     As with the earlier embodiment  300 , the line-swiveling assembly  706  is a pulley configured to engage with a resistance-transmitting line  712  to enable a pullable end of the line  712  to swivel about a vertical swivel axis, thereby allowing a user to pull the pullable end with their leg via a lower extremity receiving device  714 , or “LERD,” to perform full range of motion for any combination of hip extension and abduction. 
     From the line-swiveling assembly  706 , the resistance-transmitting line  712  is guided across the frame  704  along a pathway that runs along a diagonal boom  716  that is defined by a series of pulleys. Supporting the diagonal boom  716  are two front legs  716 ,  718  and a central rear leg  720 , all attached to the base via hinges  717 ,  719 ,  721 . These legs converge to provide structural support to the diagonal boom  716 . 
     A trapezoidal support plate  722  is attached to an upper portion of the front of the two front legs  716 ,  718  and spans the space between them, and it also abuts the underside of the gripping device  708 , supporting it from below. This support plate  722  adds a critical element of structural integrity of the entirety of the frame  704 , in its erected-for-use state. A metal crossbar  724  extends from the rear leg  720 , through a hole in the plate  722 , and over to the proximal portion of the diagonal boom  716 , for still further frame support. 
     The diagonal boom  716  is attached to the front legs  716 ,  718  via a knurled knob connector set, which secures the boom  716  tightly in its diagonal position relative to the front legs  716 ,  718 , but may be loosened to act as a hinge, and facilitate collapse. The rear leg  720  is coupled to the diagonal boom via a sliding chamber  726 . During collapse, it can act as a hinge relative to the rear leg  720  and it can slide up the diagonal boom  716 . When set for use, it is locked securely to the position of the boom  716 , by way of a locking pin. 
     From the swiveling pulley  706 , the line  714  is guided across the frame  704 . The line  714  is guided vertically upward from the swiveling pulley  706  to an intermediate guiding pulley (not shown) located at the proximal end of the diagonal boom  716 , and then diagonally upward along the boom  716  to an upper pulley (not shown) at the boom&#39;s  716  distal end, after which the line drops to connect to liftable weight  728 . The pair of boom pulleys (not shown here) together comprise a weightlifting pulley assembly. 
     In this embodiment, the line  714  is a weight machine cable configured to lift weight  728  in cooperation with the weightlifting pulley assembly, and the weight  728  to be lifted is a container of water. This type of weight complements the portable design of the apparatus itself. The container can be emptied and easily stored with the apparatus. A metric on the container  728  can indicate weight according to volume of water filled. 
     8 
       FIGS. 8A and 8B  are front oblique views of the embodiment of  FIG. 7  being used to perform hip extension and hip abduction, respectively. This pair of images graphically illustrates the importance of hip abduction as a supplement to hip extension, for the purpose of attaining a fully sculpted and shapely buttock contour, as well as maximally strengthening the gluteal musculature and thereby also the body&#39;s core. 
       FIG. 8A  is a front oblique view of the embodiment of  FIG. 7  being used to perform hip extension. Hip extension is an efficient movement for exercising the largest gluteal muscle, the gluteus maximus. A user  800  leans to shift their weight forward and assume tripod posture with both arms  802  and their standing leg  804 , as the fully extend their exercising leg  806  back. As a result, the gluteus maximus  808  of the exercising leg  806  is engaged. 
     The LERD  714  includes a loop into which a user can step to insert their foot. A horizontal opening along a distal portion of the loop receives the user&#39;s heel, enabling the LERD  714  to remain securely attached around their foot and ankle during leg motion primarily involving hip extension. In this capacity the LERD  714  enables full range of hip extension, without restricting the user&#39;s natural tendency to point their toes downward as the leg extends. 
     Despite the benefits of hip extension, this motion does not exercise the gluteus maximus  808  along the precise orientation of its fibers, nor does it even engage all of the gluteal muscles (in particular, the gluteus medius and gluteus minimus are not significantly targeted during “pure” hip extension, that is: hip extension that is not at all accompanied by hip abduction). At least some hip abduction (plus external rotation of the hip) is needed to fully activate the gluteus maximus  808 , and indeed substantial hip abduction is required to activate the glueus medius and minimus muscles. 
       FIG. 8B  is a front oblique view of the embodiment of  FIG. 7  being used to perform hip abduction. The ability to abduct the hip is indispensible in developing one&#39;s gluteal musculature. Straight abduction (shown here) works the gluteus medius and minimus muscles  809 , thereby leading to more balanced buttock strengthening and development, and more well-rounded appearance. Strategically combining hip extension with hip abduction can exercise all gluteal muscles  808 ,  809  with maximum efficiency. 
     For predominantly abducting the hip, the user can insert their foot partially into the LERD  714  so the entire distal portion of its loop wraps around the outside of their foot (rather than surrounding the heel, as in  FIG. 8A ), shown in  FIG. 8B . This technique helps to support more of the user&#39;s outer foot during hip abduction, than in the case of leg motion comprised predominantly of hip extension, where the lower leg can more easily absorb the majority of the force of resistance transmitted from the line  712 . 
     The versatile design of the LERD  714  provides a secure central attachment to the exercising foot during any combination of hip extension and hip abduction—even abduction that includes external hip rotation (which is particularly beneficial to gluteal maximus strengthening). The central attachment enables the line  712  to be guided perpendicularly away from the orientation of the foot of the abducting leg, without in any way interfering with proper form for hip abduction exercise. 
     The design of the present embodiment  700  greatly facilitates proper form for hip abduction, just as it does so for hip extension. Here, the user  800  can lean forward and assume stable tripod posture with a wide grip  802  near pelvis height, thus avoiding the strain of torsion or arching of their back. Furthermore, here the LERD  714  enables the user  800  to abduct their hip without the lateral force from the cable  712  pulling the front of their foot inward. 
     Not shown in this figure is an intermediate exercise that is half way between the two figures, ½ extension, and ½ abduction, the leg angling at a 45 degree away from the bar. The ‘45’, allows for simultaneous contraction of all three gluteus muscles, and with the combination of the LERD wrapping the lateral foot, external rotation is added to the gluteal work. The ‘45’ is the single most effective exercise to simultaneously exercise all three gluteal muscles. 
       FIGS. 8A and 8B  illustrate the wide variety of hip and leg motion that can be executed safely and with proper form under resistance, when using the embodiment  700 . Hip extension as shown in  FIG. 8A , hip abduction as shown in  FIG. 8B , and/or any combination thereof, can be performed with proper balance and optimal body mechanics. This versatility is due to the user&#39;s tripod posture, enabled by the horizontal spatial separation between the grip bar  708  and the swiveling pulley  706 , as well as by the leaning space  710  above the frame. 
     The term “tripod” underscores the enhanced stability of this specific posture that is produced by the user&#39;s two arms  802  and their standing leg  804  during exercise. Its execution depends on the swivel-grip separation. If the grip locus was not separated anteriorly from the swivel axis, then the user&#39;s grip would not be anterior to their standing leg, and thus they would not be leaning forward and/or downward with their grip. In that case, they could not be said to be in tripod posture. 
     Tripod posture further enables a user to lean away from their exercising leg to enable it to exert its full range of motion, thereby activating their gluteal muscles to the greatest extent. It also distributes the user&#39;s mass more evenly, thereby providing superior balance. Finally, by enabling the user to appropriately tilt their torso and shift more weight to their shoulders, it minimizes the potential strain on their lower back. 
     By allowing a user to work their gluteal muscles with superior efficiency and comfort, the present invention enables a user to lift more weight and perform more assertive movements than other forms of gluteal exercise generally allow. Furthermore, the ergonomic form and posture supported by the present embodiment facilitates gluteal exercise through straight-legged hip extension and hip abduction movements, thereby minimizing joint strain as well. 
     This enhanced efficiency of movements is only possible because the user  800  is able to stand in a central position that substantially straddles the swivel axis.  FIGS. 8A &amp; 8B  highlight well the versatility of this swivel straddle stance. As the user  800  exercises, they can extend and/or abduct either exercising leg  806  directly outward from the swiveling pulley  806  in whichever direction they wish, with no force vectors pulling them off course and no need to apply torque with their body. In addition, the user  800  can change up their exercise motion without having to alter their standing position, without having to contend with resistance from the cable  712  while resting in that position. 
     In these figures, the weightlifting pulley assembly is shown: the intermediate guiding pulley  810  at the proximal end of the boom  716 , and the upper boom pulley  812  at the distal end of the boom  716 . The structural integrity of the frame tripod  814  is visible here, as the user  800  leans into the approximate center of the gripping bar  708  in every exercise they perform. All legs and the extra frame supports converge to provide maximal structural integrity to this central region. 
     It should be noted that in some embodiments, a similar tripod frame can be constructed that is the converse of what is shown here: a pair of rear legs and a single central front leg. While such a tripod configuration would not have the same ease of collapsibility, it could enable the user  800  greater freedom of motion for hip flexion exercise, for example. However, the current design enables a “slide lock” collapsible frame functionality that is explored further in the next set of figures. 
     As demonstrated, the functional framework explored in  FIG. 2  is integral to the benefits described here. The key functional elements, arranged in accordance with the parameters laid out in this discussion, provide the user with a superior experience and superior results. And while other embodiments may include variations on certain structural elements, such as the configuration of their structural frame or the nature of their resistance-generating element, they nonetheless employ this same familiar functional framework. 
     9 
       FIG. 9A  is a front oblique view of the embodiment of  FIG. 7  with its frame being collapsed down into a stowable position. This figure represents a partially erected, partially collapsed state of the frame: as such, it can be considered an intermediate stage in preparation for either setup for use, or collapse for stowing. It is therefore just as instructive for understanding how the frame can be erected and readied for use from an initially collapsed position, as in understanding collapse from an erected position. 
     As shown, the water container  728  can be alternately engaged with and disengaged from a terminal locking gate  900  at the load-bearing end of the line  712 , for use and storage respectively. Furthermore, the water can be emptied from the container  728  and the container can be folded for easy storage and/or transport. For example, the container can be made of strong but deformable plastic, which can easily fold between the frame  704  and base  702  when in the collapsed state, for example. 
     The boom  716  can be disengaged from its fixed position relative to the rear leg  720  by releasing the locking pin  902  and unlocking the sliding chamber  726 . Once unlocked, the sliding chamber  726  is free to slide relative to the boom shaft  716 . Next, the metal crossbar  724  is disengaged from the boom  716  by releasing the hook on the metal crossbar  724  from its corresponding mating element (not shown) on the boom  716 . This frees the boom  716  to fold down relative to all three tipod legs  716 ,  718 ,  720 . 
     Before the boom  716  and rear leg  720  can fully collapse down, they must first be decoupled. This requires that the sliding chamber  726  be slid out towards the distal end of the boom  716 , such that the metal crossbar  724  can be retracted through the support plate that spans the space between the two front legs  716 ,  718  directly below the gripping device  708 . Once this has occurred (as in  FIG. 9A ), all frame elements are free to fold down against the plane of the base. 
       FIG. 9B  is a front oblique view of the embodiment of  FIG. 7  with its frame fully collapsed into the stowable position. The locking pin  902  that was released from the sliding chamber  726  (thereby enabling the chamber to slide relative to the boom  716 ) can now be used to secure the frame to the base  702 . In particular, the rear leg  720  is shown here receiving the locking pin  902 , which is driven through the rear leg and into the base  702  itself. The entire embodiment is collapsed to a thin profile. 
       FIG. 9C  is a perspective view of the embodiment of  FIG. 7  stowed against a wall. With its thin profile, this embodiment  700  offers many storage options. A frequent user may wish to simply stow it against a wall  904 , for example in an exercise area. Wheels  906 ,  907  are shown in this embodiment as design options for easy transport. If towed by the grip bar  708 , the base  702  can be supported by the collapsed frame as it is rolled. 
     10 
       FIG. 10A  is a front oblique view of an embodiment of the invention including an elastic band whose tension can be adjusted along a telescoping arm. The embodiment  1000  shares many structural features of the previous embodiments such as its base, swiveling pulley, adjustable gripping device, and some aspects of its frame. However, this frame is unique in its telescoping arm for elastic resistance. This elastic resistance design is robust but also quite easily collapsible and transportable. 
     While certain elements shown here (such as the frame, for example) are unique to this embodiment  1000 , the same functional framework of  FIG. 2  is present, and achieving the same benefits here as previously discussed. The structural variations of this embodiment  1000  therefore do not depart from the essence of the inventive concept. Instead, those variations commingle with and enhance the effectiveness of the functional framework, thereby asserting and demonstrating its value even more clearly. 
     The embodiment shown  1000  includes a base  1002 , a frame  1004  hingedly attached to and supported by the base  1002 , a line-swiveling assembly  1006  coupled with the base  1002 , a gripping device  1008  connected to the frame  1004 , and a leaning space  1010  that allows a user to lean their upper body for full range of exercise motion during any combination of hip extension and hip abduction, while under continuous resistance from the line  1012 . 
     The frame  1004  itself includes such sub-elements as a vertical support post  1016  connected to and supported by the base  1002 , the grip support bar  1008  coupled with and supported by the support post  1016 , and a telescoping elastic band arm  1020  (with an extension  1022 ) attached to and arising from the base  1002 . The frame  1004  also includes a pulley cross arm  1018  which extends from the elastic band arm  1020  across the vertical support post  1016  and beyond, hovering above the swiveling pulley  1006 . 
     As with earlier embodiments, the swiveling pulley  1006  engages with a resistance-transmitting line  1012 , which can be pulled with an exercising leg via the lower extremity receiving device (LERD)  1014 . The line  1012  is guided vertically upward from the swiveling pulley  1006  to a strategically placed frontal guiding pulley  1024  (the intermediate guiding pulley according to the functional framework) located at the front terminus of the pulley cross bar, and then guided across the frame  1004 : horizontally to a rear guiding pulley  1026 , located near the rear terminus of the pulley cross arm  1018 . 
     From the rear guiding pulley  1026 , the line  1012  is guided vertically upward along the telescoping arm  1020  and its extension  1022 , to ultimately connect to an elastic resistance band  1028  via a connecting element, such as a ring or locking loop. The elastic resistance band  1028  itself runs around an elastic band pulley  1030  attached to an distal portion of the arm extension  1022 , and then drops down to connect with an elastic band anchor  1032  (which is connected to the bottom of the telescoping arm  1020 , near the base  1002 ). 
     In the embodiment shown, the telescoping arm  1020  is hingedly attached to the vertical support post  1016 . The vertical support post  1016  itself is supported and locked into its vertical use-ready position by a base buttress hinge  1034 . The base buttress hinge  1034  holds the vertical support post  1016  securely in the vertical position relative to a baseplate  1036 , which itself is attached to the base  1002 . The support post  1016  is hingedly connected to the baseplate  1036 , and can be folded down when unlocked from the base buttress hinge  1034 . 
     The frontal guiding pulley  1024 , rear guiding pulley  1026 , and elastic band pulley  1030 , function together as a resistance-activating pulley assembly. This “band-stretching” resistance-activating pulley assembly facilitates stretching of the elastic band  1028 , which is the means for generating resistance against the pulling of the resistance-transmitting line  1012 . Alternative resistance-generating elements other than an elastic band, such as liftable weight or a flexible rod a spring, and still others, will be readily apparent to or within the contemplation of one of ordinary skill in the art. 
     In the embodiment shown, the resistance transmitted by the line  1012  is generated by the stretching of an interchangeable elastic resistance band.  1028  when the pullable end of the line  1012  is pulled with sufficient force. Unlike lifted weights, elastic bands can generate resistance that cannot be diminished via quickly accelerated motion. A combination of bands can be attached to the cable  1312  for added resistance. 
     A key advantage of resistance generated by an elastic band  1028  is the linear variability of its resistance. Linear variable resistance is resistance that increases in roughly linear proportion to the amount that a band has already been stretched, which many exercise enthusiasts find particularly beneficial for certain types of exercise. The reason linear variable resistance is often considered so advantageous and conducive to muscle building is that it engages muscles with greater resistance as the muscle&#39;s own strength capacity increases, requiring the greatest pulling force at the very apex of an exercise repetition. 
     As with earlier embodiments, various components of the frame  1004  may be adjusted. Here, the position of the gripping device  1008  can be adjusted in the vertical dimension. The height of the gripping device  1008  is controlled by a grip height adjustment system that extends the vertical support post up and down. Furthermore, the tension of a given elastic band  1028  can be adjusted by telescoping arm  1020 , given how far its extension arm  1028  is projected upward. 
       FIG. 10B  is a profile view of the embodiment of  FIG. 10A . In this view, the course of the line  1012  from LERD connection, to swivel pulley  1006 , to intermediate guiding pulley  1024 , and ultimately to the elastic resistance connection  1028  can easily be traced. One hole of the telescopic extension  1022  can be seen to demonstrate the adjustable height of the elastic support tower. 
     Also the connection mechanism of the interchangeable elastic band attaching to the tower base attachment  1032 , and the line attachment other end, allowing for easy interchange of various different elastic strength units. In this view, a vertical support post hinge  1038  can be seen inside the base buttress hinge  1034 , enabling the vertical support post  1016  itself to be folded down adjacent to and parallel with the base  1002 . Also in view in this figure is a telescoping arm hinge  1040 , which enables the telescoping arm  1020  to be folded down against the folded-down vertical support post  1016 , once again parallel to the base  1002 . 
       FIG. 10C  is a front oblique view of the embodiment of  FIG. 10A  with its frame fully collapsed into a stowable position. The vertical support post  1016  has been folded all the way down against the top surface of the base  1002 , adjacent to and parallel with it. The telescoping arm  1020  has also been folded down, adjacent to the vertical support post  1018  and also parallel with the base  1002 . In this highly compact state, this embodiment  1000  can be easily stowed in a variety of different locations. 
     11 
       FIG. 11A  is a front oblique view of an embodiment of the invention including an elastic band whose tension can be adjusted by a hand crank. The embodiment  1100  shares many structural features of the previous embodiments such as its base, swiveling pulley, gripping device, and some aspects of its frame. However, this frame is unique for being positioned at a rear edge of the base  1002 , spanning the full width of that edge. 
     While certain elements shown here (such as the frame, for example) are unique to this embodiment  1100 , the same functional framework of  FIG. 2  is present, and achieving the same benefits here as previously discussed. The structural variations of this embodiment  1100  therefore do not depart from the essence of the inventive concept. Instead, those variations commingle with and enhance the effectiveness of the functional framework, thereby asserting and demonstrating its value even more clearly. 
     The embodiment shown  1100  includes a base  1102 , a frame  1104  hingedly attached to and supported by the base  1102 , a line-swiveling assembly  1106  coupled with the base  1102 , a gripping device  1108  connected to the frame  1104 , and a leaning space  1110  that allows a user to lean their upper body for full range of exercise motion during any combination of hip extension and hip abduction, while under continuous resistance from the line  1112 . 
     The frame  1104  itself includes such sub-elements as two side support posts  1116 ,  1117  connected to and supported by the base  1102 , a grip support bar  1108  supported by the support posts  1116 ,  1117 , and a pulley arm  1118 , which is attached to and extends from a frame cross bar  1120  that spans the space between the two support posts  1116 ,  1117 . The frame  1104  also includes support struts  1122 ,  1123  to support the frame  1104  upright, and hinges  1124 ,  1125  for folding the frame  1104  down. 
     As with earlier embodiments, the swiveling pulley  1106  engages with a resistance-transmitting line  1112 , which can be pulled with an exercising leg via the lower extremity receiving device (LERD)  1114 . The line  1112  is guided vertically upward from the swiveling pulley  1106  to a strategically placed frontal guiding pulley  1126  (the intermediate guiding pulley according to the functional framework) located at the front terminus of the pulley arm  1118 , and is then guided across the pulley arm  1118 , and across the elastic band assembly. 
     An elastic resistance generating assembly includes a resistance-generating pulley assembly, which communicates with the resistance-transmitting line  1112 , an elastic resistance band  1128  connected to the distal end of the resistance-transmitting line  1112 , and finally a tension-adjusting line  1130  connected to the distal end of the elastic resistance band  1128 . The tension adjusting line  1130  feeds into a hand crank which can feed the line  1130  the tension of the elastic resistance band  1128  itself. 
       FIG. 11B  is a rear view of the embodiment of  FIG. 11A . A rear guiding pulley  1132  attached horizontally to the pulley arm  1118  via a rear pulley guiding pulley housing  1134  receives the line  1112 , and it is fed into the elastic resistance generating assembly, which includes two line pulleys  1140 ,  1141  three elastic band pulleys  1142 ,  1143 ,  1144 , and a hand crank  1145  for drawing in the tension adjusting line  1130  and thereby increasing tension of the elastic resistance band  1128 . 
     The elastic resistance generating assembly pulleys and hand crank  1145  are attached to the rear surface of the two side support posts  1116 ,  1117 . The pulley arm  1118  is capable of turning on an axis  1136 , thereby folding into the plane of the frame. For use, however, it is locked into place with a locking pin  1138 . To fold the pulley arm into the frame, the locking pin  1138  can be removed. Then, the entire frame can be folded down to the base. 
       FIG. 11C  is a front oblique view of the embodiment of  FIG. 11A  with its frame fully collapsed into a stowable position. The pulley arm  1118  has been folded into the plane of the side support arms  1116 ,  1117  and the entire frame has been folded down to be adjacent to and parallel with the base  1102 . In this highly compact state, this embodiment  1100  can be stowed in a variety of different locations. It can also be carried somewhat like a suitcase, with the grip bar  1108  as a handle. 
       FIG. 12A  is a front oblique view of an embodiment of the invention that can use the resistance of a general purpose exercise machine. The embodiment  1200  shares many structural features of the previous embodiments such as its base, swiveling pulley, gripping device, and some aspects of its frame. However, this embodiment  1200  is unique in that it does not supply its own resistance-generating element or resistance-transmitting line, but rather incorporates those of another machine  1201   
     While certain elements shown here (such as the frame, for example) are unique to this embodiment  11100 , the same functional framework of  FIG. 2  is present, and achieving the same benefits here as previously discussed. The structural variations of this embodiment  1100  therefore do not depart from the essence of the inventive concept. Instead, those variations commingle with and enhance the effectiveness of the functional framework, thereby asserting and demonstrating its value even more clearly. 
     The embodiment shown  1200  includes a base  1202 , a frame  1204  hingedly attached to and supported by the base  1202 , a line-swiveling assembly  1206  coupled with the base  1202 , a gripping device  1208  connected to the frame  1204 , and a leaning space  1210  that allows a user to lean their upper body for full range of exercise motion during any combination of hip extension and hip abduction, while under continuous resistance from the line  1212 . 
     The frame  1204  itself includes such sub-elements as two support posts  1216 ,  1217  hingedly connected to and supported by the base  1202 , a grip support bar  1208  supported by the support posts  1216 ,  1217 , and a pulley cross arm  1218 , which is attached to the right support post  1217 . The frame  1204  also includes a support wing  1220  hingedly attached to the right support post  1217 , which can help counter torque that is generated by the load-bearing line  1212  running off-center on the base  1202 . 
     The support posts  1216 ,  1217  are connected via a bottom supportive crossbar  1222 , which stands on the base  1202  and supports the frame  1204  in its upright and use-ready state, but which lifts off the base when the frame  1204  is folded down. A base cutout  1224  enables the embodiment  1200  to get close to a neighboring machine  1201  whose own cable connects to the line  1212 , and its associated liftable weight, while hinges  1226  enable the frame  1204  to fold down or be lifted upright. 
     As with earlier embodiments, the swiveling pulley  1206  engages with a resistance-transmitting line  1212  that can be pulled with an exercising leg via the lower extremity receiving device (LERD)  1214 . The line  1212  is guided vertically upward from the swiveling pulley  1206  to a strategically placed frontal guiding pulley (the intermediate guiding pulley according to the functional framework) located at the front terminus of the pulley cross bar, and then guided across the frame  1204 : horizontally to a rear guiding pulley located at the rear terminus of the pulley cross arm  1218 . 
     From the rear guiding pulley, the resistance-transmitting line  1012  is guided vertically upward. The line  1212  for this embodiment  1200  connects to a line from a neighboring machine  1201 , which in this figure is a multipurpose weight machine. As the  1212  line is guided upward from the embodiment  1200  and runs into a new line, the new line encounters a sliding pulley  1228  which is capable of sliding up and down a vertical track. From there, the line  1212  is fed through a pulley assembly and down to liftable weight. 
     The embodiment shown  1200  enhances the exercise options of the multipurpose machine  1201 . If a user tried performing hip extension and/or hip abduction with the multipurpose machine  1201  itself, they not have a grip to enable tripod posture, nor would they have the space to lean forward during hip extension. Unable to execute the proper posture during hip extension, a user would naturally flex their knee and engage their hamstring, at the expense of the gluteal muscles. 
     Furthermore, hip abduction would be just as severely compromised without a true gripping device that a user could grasp to counter the torque created on their body from their abducting leg. In both of these cases, the multipurpose machine  1201  would not provide an optimal gluteal exercise experience. When the multipurpose machine  1201  is supplemented with the present embodiment  1200 , however, great value is added to the user&#39;s gluteal exercise repertoire, with such a lightweight device. 
       FIG. 12B  is a front oblique view of the embodiment of  FIG. 12A  with its frame fully collapsed into a stowable position. The pulley arm  1218  has been folded into the plane of the support arms and the entire frame has been folded down to be adjacent to and parallel with the base  1102 . The support wing  1220  has been folded away from its stopper  1230  and down against the rest of the frame and the base  1202 . In this highly compact state, this embodiment  1100  can be stowed discreetly in a variety of different locations.