Patent Publication Number: US-6217487-B1

Title: Quadruped-type exercise apparatus for humans and method of exercising

Description:
FIELD OF THE INVENTION 
     This invention relates to walking- or running-type exercise machines and more particularly to treadmill-type exercisers. More particularly still, the invention relates to a multiple treadmill-type exerciser configured to allow a human subject to assume the gait of a quadruped in order to burn calories more quickly and add interest to exercise routines, especially for children and the young at heart, as well as a method of exercising the human body in a quadruped manner. 
     DISCUSSION OF THE PRIOR ART 
     A plurality of machines have been developed to facilitate exercise in restricted and frequently inconvenient places and times, either at home or in commercial or educational institutions where both time and space may be at a premium. Among such apparatus may be running or walking treadmills, stationary bicycle-type machines, artificial stair climbing apparatus, often referred to as “steppers”, simulated ski movement apparatus, weight-lifting apparatus and the like. 
     In the particular case of treadmill-type exercise equipment, exercise is obtained by walking or running in position on the piece of equipment, thus simulating normal walking or running on an indoor or outdoor track. Such treadmills usually comprise a rubberized support belt which is carried upon multiple axles which turn as the belt passes unidirectionally beneath the feet of the user. In most modern treadmills, the traveling belt is adjustable for various angles, and the support axles may be power driven for independent rotation without regard for the user, allowing such user to merely walk or run in place. 
     In a second, usually older-type, apparatus, the motion of the user will cause movement of the treadmill. Usually in these older treadmills, the user will grasp hold of side rails or the like so as to have a stationary point which is maintained constant relative to the belt, while the forward to back or back and forth motion of the legs of the user serves to keep the belt moving. In a variation of such apparatus, the user may be prevented or retarded from moving forward on the belt by a transverse waist-height bar over the belt, or by being tied or secured in place on the belt usually by a belt or fastening about the waist of the user which is secured to a post or the like on the base of the treadmill apparatus. In all such non-motorized apparatus, while the overall walking or running movement is less natural, more calories are expended in maintaining the motion so that more overall exercise is obtained by the user in any given period than by the use of a motorized treadmill. 
     In addition to the above, it is not unusual for a treadmill-type apparatus to be equipped with an arm exercise apparatus, especially of the weighted pulley-type, allowing the arms to be moved in unison with the striding legs. A more extreme form of such an arrangement is typically provided in ski-type exercisers where the alternate sliding forward and backward of the foot pieces or supports is typically accompanied by an opposite, but coordinated, tension on weighted cables attached to the hand grips or hand levers attached to spring biasing means, thus providing simultaneous whole body exercise. 
     Treadmill-type apparatus has also been provided for animals, such as dogs and racehorses, to provide exercise for such animals where running or walking in the open may not be practical or convenient. In some cases, the treadmills have incorporated separate belts for the legs of the animal on both sides. Frequently, the animal is strapped into position to keep it from wandering off, or, as in older human treadmill apparatus, to provide the restraint to forward motion that allows the movement of the animals feet to propel the treadmill itself. Alternatively, the treadmills themselves may be motorized to ensure continuous or uniform movement. 
     Modern treadmills are frequently adjustably angled or slantable in order to vary the effort required to operate them. For example, if the treadmill is slanted, the use of it simulates walking uphill because each forward step requires a step up followed by forcing the treadmill downwardly by the force of the legs in a similar manner to lifting the body by the force of the legs when actually climbing a hill. Medical stress test treadmills regularly use this feature to provide progressive degrees of exertion. 
     It has been frequently found to be difficult to provide exercise apparatus that will encourage relatively young or immature persons to begin with, as well as to stick to, an exercise routine because of the relative lack of interest inspired by the available equipment. Yet it can be quite important to instill an early inclination for exercise in young children to ensure such activity will be followed later in life. 
     A general survey of treadmill types may be obtained by reference to the following U.S. Patents directed to such apparatus: 
     U.S. Pat. No. 219,439 issued Sep. 9, 1879 to L. H. Blend discloses a passive-motion walking machine designed for therapeutic use for treatment of conditions such as paralysis and curvature of the spine by producing a passive motion similar to natural walking, and combined with the partial suspension of the patient&#39;s body by the waist or head by a pair of straps. 
     U.S. Pat. No. 1,766,089 issued Jun. 24, 1930 to A. J. Wood discloses a treadmill exercising device for simulating natural walking or running motions. The treadmill platform is composed of a plurality of supporting rollers on which a single endless tread belt is placed. The platform may be adjustably inclined to simulate uphill walking, and a pair of straps may be attached to a handrail and then loosely tied around the operator&#39;s waist to maintain the position and stance of the user. 
     U.S. Pat. No. 2,017,138 issued Oct. 15, 1935 to F. O&#39;Neill, Jr. discloses a treadmill device with curved guides or flanges attached to both ends of a metal base on which a continuous belt is attached. A spring tension belt may be attached to a handrail and placed around the waist of the operator to give an upward lift to the abdominal organs. 
     U.S. Pat. No. 2,155,684 issued Apr. 25, 1989 to J. R. Richards discloses an animal exercising device of the treadmill variety in which the animal is strapped to a pair of guardrails or guide rails with a harness in a manner such that the animal may walk or run as appropriate as the inclination of the tread is adjusted. 
     U.S. Pat. No. 4,204,673 issued May 27, 1980 to J. Speer, Sr. discloses a treadmill exerciser having two separate treadmills adjacent each other with separate continuous treads. 
     U.S. Pat. No. 4,861,021 issued Aug. 29, 1989 to M. Edwards et al. discloses a safety harness on/off switch assembly for use with motorized treadmills in which a pair of interconnected straps are suspended from a support with loops on each strap to support the user. 
     U.S. Pat. No. 5,100,127 issued Mar. 31, 1992 to D. Melnick et al. discloses a complex, multipurpose exercise treadmill designed for quadrupeds, particularly racehorses. The device comprises a tripartite frame structure and treadmill floor surface provided with shock-absorbing means and a vertically-extending mast to which a belt adapted for use by a quadruped is attached. 
     While the various devices shown and described in the foregoing patents may be effective within the scope of their designs to provide various amounts of exercise to the users, there is actually a rather limited repertoire of movements and varieties of exercise available with various treadmill-type exercise machines. There has been a need, therefore, to provide exercise machines facilitating a greater variety of exercise movements. There has also been a need to provide an exercise apparatus that will embody various advantages including preferably having some inherent quality which may lead many people to test or try it, and eventually to use it or other equivalent apparatus on a regular basis. 
     In addition, while young persons have frequently imitated quadrupeds by walking or running like four-footed animals, sometimes with bent legs to avoid the elevation of their buttocks at an inconvenient angle, only the very young have been normally able to do so without such an awkward elevation of the buttocks due to the difference in the normal lengths of human legs and arms. On the other hand, movement of the body in a quadruped stance is a very effective way to obtain a thorough workout of the muscle system of substantially the entire body. 
     OBJECTS OF THE INVENTION 
     It is an object of the invention, therefore, to provide an exercise machine that will allow the user to proceed in the manner of a quadruped on the surface of such apparatus. 
     It is a further object of the invention to provide an exercise apparatus that provides separate moving treads for each of the four limbs of a user when the user adopts a quadruped gait. 
     It is a still further object of the invention to provide an exercise device of the treadmill-type that may be adjusted for various speeds of movement. 
     It is a still further object of the invention to provide an exercise apparatus that includes a support means to aid in support of the body of the user during sustained exercise. 
     It is a still further object of the invention to provide an exercise apparatus that will appeal to persons of all ages, particularly young persons. 
     It is a still further object of the invention to provide an exercise apparatus that provides a different movement, and exercises different muscles than other exercise apparatus. 
     It is a still further object of the invention to provide an exercise apparatus that is particularly effective in burning up calories while placing relatively little stress on the body&#39;s spine and joints. 
     It is a still further object of the invention to provide an exercise apparatus that exercises the entire body while placing minimal stress on the spine and joints. 
     It is a still further object of the invention to provide an exercise apparatus which stresses the muscles and provides abdominal support during motion. 
     It is a still further object of the invention to provide a novel method of exercising that gently stresses and exercises a majority of the muscles of the body while relieving stress and avoiding excess blood pressure elevation. 
     It is a still further object of the invention to provide a quadrupedal exercising device in which rear treads for the feet are positioned at a lower elevation than forward treads for receiving the hands of the user. 
     It is a still further object of the invention to provide a quadrupedal exercising device in which the forward treads for the hands are divided into two treads positioned forwardly but preferably partially overlapping a single rearward tread for the feet. 
     It is a still further object of the invention to provide a quadrupedal exercising device having a longitudinally moveable suspension belt suspension point over the treads. 
     Additional advantages and objects of the invention will become evident from review of the accompanying drawings in conjunction with the following description and discussion. 
     BRIEF DESCRIPTION OF THE INVENTION 
     A multiple tread apparatus is provided in which there are at least two endless moveable treads, one positioned at a higher level than the other, such that a user may be supported in a quadruped position upon said endless treads with the back, or spine, of the user aligned or held in a relatively straight, substantially horizontal position. The two treads may be operated either by the force of the user or may be separately mechanically operated by motors. There is also preferably provided a belt arrangement for passing around the abdomen of the user, partially supporting the user as well as maintaining the straight alignment of the abdominals. The belt is supported in any suitable manner from a boom arrangement, which is either part of the support for the endless belts or a separate arrangement placed adjacent to the apparatus. Preferably, the treads will be in the form of two adjacent upper treads to accommodate the hands of the user, and one lower tread to accommodate the feet for a total of three separate treads. However, two lower treads may also be provided for use separately by each leg for a total of four separate treads. The apparatus may be permanently situated in a position for use in a quadruped manner, either with the treads horizontal to the support surface upon which the apparatus rests, or with the treads angled upwardly to provide additional exercise. The hand support treads may also be arranged to be brought upwardly sufficiently so they will be adjacent to the user, or at the level of comfortable contact by the hands of the user, when in an erect position. A sliding arrangement may be provided for the suspension of the support belt to avoid pronounced pivoting of said suspended support if the user of the apparatus looses their balance or quadruped stride. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a partially cut away diagrammatic side elevation of the apparatus of the invention with a user, shown in phantom, supported from a belt arrangement over the tread apparatus. 
     FIG. 2 is a diagrammatic front elevation showing the apparatus shown in FIG. 1 in use. 
     FIG. 3 is an isometric side elevation showing the apparatus of the invention ready for use. 
     FIG. 3A is a side view of a jam-type screw fitting for use with the apparatus of the invention. 
     FIG. 4 is a frontal isometric view of a portion of the apparatus showing the support arrangement for the arm exercising belts of the invention. 
     FIG. 5 is a partial isometric view of one side of the apparatus illustrating the adjustment features for the foot tread belt, as well as the mounting of the boom arrangement. 
     FIG. 6 is a partial view of the support plates for the adjustable foot portion of the apparatus illustrating the interaction of the support plate and adjustable plate and their adjustment features. 
     FIG. 7 is an isometric view of an alternative, partially disassembled support arrangement for one of the adjustable hand belts of the invention. 
     FIG. 8 is an isometric view, partially in phantom, illustrating an alternative arrangement for adjustment of the hand belts of the invention. 
     FIG. 9 is a partial isometric view of a screw thread adjustment for use in adjusting the elevation of the hand treads of the apparatus of the invention. 
     FIG. 10 is a further detail of the arrangement shown in FIG.  9 . 
     FIG. 11 is a further detail of an alternative to the arrangements shown in FIGS. 9 and 10. 
     FIG. 12 is an enlarged isometric view of an adjustable arrangement for the boom of the invention. 
     FIG. 13 is a diagrammatic side elevation of an alternative embodiment as compared with that shown in FIG. 1, where the tread surface as a whole is comprised of one continuous belt rather than two. 
     FIG. 14 is a side perspective elevation of an alternative embodiment as compared with that shown in FIG. 3, where the hand tread surface is comprised of one continuous belt rather than two separate belts. 
     FIG. 15 is an isometric view of an alternative embodiment of the invention having a pivoting boom and slide attachment for the supporting belt to provide some longitudinal adjustment potential for the belt. 
     FIG. 16 is a diagrammatic side view of an embodiment of the invention having a slightly rearwardly and upwardly inclined slide bar to which the supporting belt is slideably secured to allow limited longitudinal adjustment of said belt. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     A number of exercise apparatus have been invented in recent years to enable persons to obtain the regular exercise necessary for continuous good health and well being. Such exercising apparatus has fallen naturally into two main types, one to exercise the legs and the other to exercise the arms. One of the principal exercise apparatus for the legs is the treadmill, in which the user either walks, trots, or runs in place on a moving tread which is powered by either the motion of the user or a motor. 
     The other large use of exercise devices has involved various weights, springs, pulleys with weights, levers and the like for exercising the arms, wherein a handlebar or other handgrip or the like is grasped by the user and force, derived either from spring means or from weight means, is applied in opposition to the movement of the arms. While many of these prior exercise apparatus have been relatively sophisticated, all of them have the constraint that only certain muscles are used for each exercise routine available on the apparatus. 
     One of the most commercially successful total body exercisers for obtaining fairly vigorous exercise has been the so-called Nordic Track and its imitators. The legs and arms are simultaneously subjected to a back-and-forth movement, producing a total effect similar to the movements of a cross-country skier. However, even these popular apparatus have certain constraints with respect to the number of the muscles or muscle systems exercised during a given workout. 
     Another excellent exercise is swimming, wherein the amount of exercise is proportional to how vigorously the person swims. However, the difficulty with swimming is that a pool is not consistently and conveniently available to everyone. While certain sophisticated swimming devices in which the user swims against a predetermined variable current in a relatively restricted space are coming presently into use, these are available only to those who can afford access to them The benefit of swimming as an exercise is that it is almost impossible to injure the joints, although an occasional cramp may result from which recovery is usually fairly rapid. 
     The present inventor has realized that a high degree of intense exercise for both the muscles of the legs and the arms may be obtained if the subject exercises with the legs and arms while supported in a quadruped position. While such an exercise position and support arrangement may at first seem rather awkward, it is actually relatively natural, even for a human body, because the human bipedal body evolved from an intermediate quadrupedal form with only fairly minor changes in anatomy and physiology. Consequently, the quadrupedal stance may be assumed by humans in relative comfort when the correct apparatus is provided. The main difficulty for a human body in assuming a comfortable quadruped stance is the fact that the bipedal evolvement of humans has resulted in significantly longer legs than arms, so that in assuming a quadrupedal posture, the hips will normally be raised significantly over the shoulders and the head will be thrust downward in a rather uncomfortable position, from which, in an older person, it may even be difficult to look straight ahead unless the legs are maintained in an inconveniently bent position, in which position, however, they will be found to tire very rapidly. Thus, although treadmill apparatus have been designed for use by actual quadrupeds such as dogs, horses and the like, use of such animal treadmills are not comfortable for the usual bipedal human. 
     The present inventor realized that if two levels of treadmill belts are provided, one of which is above or more elevated than the other and forwardly disposed with respect to the other, that the legs may be easily accommodated on the rear belt while the hands may be comfortably accommodated on the forward belt, with the spine and the neck maintained in a fairly straight line. Even more comfortably, the treads for the arms may be moved upwardly resulting in a more comfortable, slight incline of the back or spine and resulting position of the head. 
     The present inventor, by studying the development of the human body whose ancestors had wide shoulders and narrow hips, has discovered while designing his two-part quadrupedal treadmill arrangement for humans, that the forward treadmill may be easily separated into two distinct treads displaced to the side and arranged outboardly of the treads for the legs. A preferred arrangement of a treadmill for a quadrupedal stance of a human, therefore, will have two separate hand support treads, positioned more or less outboard of, in front and at a higher elevation than the treads arranged for the legs. 
     Preferably in the arrangement of the invention, the various treads will be inclinably adjustable with respect to the floor as with normal treadmills. The forward and rear treads should also be vertically adjustable relative to each other to accommodate users with varying leg and arm dimensions and differences. 
     The invention allows the user to exercise almost all the muscles in his or her arms and legs, as well as many other bodily muscles, and the vigorousness of such exercise is also variable with respect to the user&#39;s exertion. A support belt is provided, preferably used about the middle of the user, to partially relieve the weight of the major portions of the body from the arms and legs, as well as to hold the user fairly stationary with respect to any forward or backward motion, allowing exercise to occur in a more relaxed manner. In addition, the belt tends to restrain the abdominal section of the body, preventing this area from sagging and allowing the muscles to work more efficiently. 
     The apparatus of the invention, therefore, has many advantages, only some of which have been set forth above. A better understanding of the invention will be garnered from study of the attached drawings in connection with the following description keyed to said drawings. 
     FIG. 1 is a diagrammatic partially cut away side elevation showing in phantom a human figure making use of a quadrupedal exercising apparatus in accordance with the invention. In FIG. 1, a base  11  has mounted thereupon a side support plate  13 , which is shown, for convenience, as a triangular plate attached to one side of the base  11 . It will be understood that the side support plate  13 , while shown as a unitary plate, may be in the form of a discontinuous plate or even a framework extending upwardly to a point at which a laterally extending boom  15  may extend from the plate  13 . It will be understood that the boom  15  extends outwardly towards the observer over the top of the user, represented by the human FIG. 17, who is supported or partially supported from a belt  19  which wraps around the central portion, or waist  21 , of the user of the apparatus and is secured at the top to an eyelet-type support coupling  23  which secures the belt  19  to the boom  15 . Braces  25  extend on all sides of the boom  15  near the support plate  13  and serve to support or stabilize the boom  15  in its outwardly extending position. See FIG.  2 . At the lower portion of the side support plate  13 , and also attached to the base  11 , is a second sturdy support plate  27  to which the side support plate  13  is attached, and which extends upwardly from the base  11  an adequate height to support the tread apparatus  29  and  31 . There are two hand tread apparatus  29  for contact with the hands  17   a  of the user, the second set  29   a  being supported by a support plate  27   a,  not shown in FIG. 1, but shown in FIG. 2, and one foot tread apparatus  31  for support of the user&#39;s feet, one side of which foot tread apparatus is supported by support plate  27  and the other side by support plate  27   a.  Each of the tread apparatus  29  and  29   a  are comprised of support roles  33  and  35 , journaled on shafts  37  and  39  which are suitably rotatably journaled in the support plates  27  or  27   a  so that they extend horizontally out from such plates  27  and  27   a.  It should be understood that the axles  37  and  39  may normally be journaled, not only at the one end in the support plate  27 , but in a similar support plate, not shown, or other support arrangement on their opposite ends so that the journals are supported on both ends for more security and vibration-free movement. Such axles may also be journaled, however, only at one end as shown particularly in FIG.  2 . About the rollers  33  and  35  is wound, or passes, a flexible tread  41  which will be moved in an endless loop about the support rollers  33  and  35 . The travel or movement of the tread  41 , which is preferably a rubberized, flexible tread, may be caused either by the backward pressure of the hand  17   a  of the user  17 , or by suitable motorization of the rollers  33  and  35 , not illustrated in FIG. 1, but represented in FIG. 2 by the motors  46 , the shafts of which pass through or are journalled in the support plates  27  and  27   a  and are secured to one of the axles  37  and  39  of the rolls  33  and  35 . 
     Also journaled on the support plates  27  and  27   a  are two lower rollers  43  and  45  journaled on axles  47  and  49  in a position such that a flexible tread  51  passed about the rollers  43  and  45  will contact and support the feet  17   b  of the user  17 . In a manner similar to the flexible hand tread  41 , the flexible foot tread  51  may be driven about the rollers  43  and  45  either by the backward pressure of the feet of the user  17  or by motorized means, not specifically shown in FIG. 1, but similar to the motorization of any conventional tread machine and shown diagrammatically in FIG. 2 by belt connection  60   b  from motor  46  through journal extension  47 . 
     FIG. 2 is a diagrammatic front elevation of a preferred embodiment of the apparatus shown in FIG.  1 . In such preferred embodiment, the tread  41 , is divided with respect to the user  17  into a right portion  41   a  and a left portion  41   b,  where tread  41   a  is supported upon the journals  37  and  39 , see FIG. 1, which are in turn journaled in support plate  27 , and in the case of tread  41   b,  are supported on the journals  37   a  and a rear journal not shown, but similar to journal  39  shown in FIG. 1, which are in turn rotatably journaled in the support plate  27   a.  Likewise, the tread  51  is supported on journals  47  and  49  which are supported on both sides in the support plates  27  and  27   a.  It will be understood that the two treads  41   a  and  41   b  could also be in the form of a single tread which would extend between the plates  27  and  27   a  in a manner similar to the foot tread  51 , since as can be seen in FIG. 1, the two treads  51  and  41  are displaced not only with respect to elevation, but with respect to longitudinal position on the base  11  so that the upper tread  41  will not interfere with use of the lower tread  51 , even if the tread  41  extended all the way across the apparatus. However, since the evolution of the human body demonstrates a broad shoulder girdle, effectively positioning the hands and arms relatively displaced to the side, it is convenient to use two treads as shown, i.e. as two separate treads  41   a  and  41   b,  to support the arms of a user and only one or a single tread to support the legs of the user, since the feet are usually placed fairly close together not only on the human body, but also on any supporting surface. However, it will be understood that the foot tread could also be designed with two independently operating surface treads, even though the two tread sections would be placed closer together than the hand treads. Thus, while it is convenient to construct the apparatus with two upper treads designed for the hands and with a single foot tread designed to support and move with the feet of the user, it will be understood that either the hand treads could be designed to be a unitary tread, or the foot treads could be designed to be bipartite, or in two parts, similar to the preferred arrangement of the hand treads. Thus the design of the apparatus which is based ultimately upon the anatomy of the user, can be varied and still remain operative. The principal requirement is that the forward hand tread be arrangeable so that it is relatively higher than the foot tread thereby allowing for the relatively shorter arms of the normal human body with respect to the legs, and allowing the body itself to assume a relatively horizontal position when using the exercise device of the invention. The treads  41   a,    41   b  and  51  may be motorized to travel or move automatically by means of the motors  46  and  46   a  shown in FIG. 2, each of which is attached to the journals  37  and  37   a  and  47  of the tread supporting rolls by couplings  60   a  or drive belts  60   b.  The motors  46  and  46   a  are also each supported by motor mounts or brackets  60   c  secured to the support plates  27  and  27   a.    
     FIG. 3 is an isometric view of the apparatus of the invention showing the two treads  41   a  and  41   b  rotatably supported from the support plates  27  and  27   a,  while the single lower rearwardly positioned tread  51  is supported on rollers  43  and  45 , which are in turn, rotatably supported from the side plates  27  and  27   a.  Portions of the treads  41   b  and  51  are shown in phantom behind the supporting plate  27   a.  It will be understood that the journaling of the rollers  33  and  35  will be relatively securely supported when journalled upon only one side, i.e. in the support plate  27 . However, the ensuing wear may also be relatively severe in the journals and such wear could be decreased by extending the journalled rollers  37  and  39  across from the one tread  41   a  to the other tread  41   b.  This would not interfere with the operation because the legs of the user contact the tread  51  of the apparatus well behind the journals  37  and  39 . There are also shown in FIG. 3, additional adjusting plates  53 ,  55  and  57 , and  59  respectively, for the hand treads  41   a  and  41   b  and the foot tread  51 . A further adjusting plate  59  on the near side of the apparatus for the foot tread is also shown along its upper and right-handed sections. The adjustment plates  53 ,  55 ,  57  and  59  are provided with curved slots in their surfaces, so that if one end of the plates  53  through  59  is raised with respect to the other end, that is to say with a pivoting movement, the slot will allow the far end to pivot. This allows the relative inclination of the treads  41   a,    41   b  and  51  to be adjusted, primarily from a horizontal to an inclined position. At the same time, adjacent slots  63  are provided in the outside support plates  27  and  27   a.  Jam-type fastenings  65 , shown in FIG. 3A, having a central externally threaded section  67  and internally threaded end caps  69  and  69   a  with wings or finger tabs  70  on their surfaces to facilitate tightening or untightening, pass through the opposed curved slots  61  and straight slots  63 . See, in particular, FIG.  6 . When the jam-type fastenings  65  are loosened on both sides of the apparatus, the adjustment plates  53  and  55 ,  57  and  59 , may be moved relative to the support plates  27  and  27   a.  If it is desired to move the entire tread sections  41   a,    41   b  or  51  up or down, the jam-type fastening  65  will be moved upwardly or downwardly in the straight slots  63  in the support plates, thus adjusting the relative heights of the two sets of treads  41   a  and  41   b  and  51 . If it is desired to slant the tread surfaces  41   a,    41   b  or  51  from one end to the other so that one end is higher than the other, only one end of the adjustment plates  53 ,  55 ,  57  or  59  will be moved in an arc corresponding to the curvature of the curved slots  61 . Thus, the apparatus as shown in FIG. 3 allows adjustment of the tread surfaces to adapt to the size of the person who will use the apparatus, the relative length of their legs and arms, and also allows the slope of the treads to be adjusted so that the intensity of the exercise may be varied. In FIG. 3, the bottom plane or lower surface of the adjusting plates  53  and  57  and the outer end of plate  59  are shown with an arcuate curvature at their two lower extremities  62  to allow them to be more easily tilted to an angle in accordance with the arcuate shape of the adjustment slots  61 . 
     As will be understood, the arrangements shown in FIG. 3, while effective with respect to adjustment of the treads and support of the treads, places a relatively large force upon the journals of the hand treads  41   a  and  41   b  because the rolls  33  and  35  are supported only at one end, causing a large moment of turning movement or twisting upon the journals. 
     It will also be recognized that the relatively simple arrangement shown in FIG. 2, for example, for connecting the shafts of motors  46  to the shafts of the rolls  33  and  35  and  43  and  45  may have to be modified in order to effectively keep the motors aligned with the shafts of the rolls. Ways of accomplishing such alignment will occur to those skilled in the art. 
     FIG. 4 shows an improvement in the arrangement to support the journals of the rolls in which both ends of the journals may be supported. In this arrangement, the adjustment plates  53  and  55 , rather than being merely flat plates, are formed as channels  77  having an inside section, or flange,  75 , a lower section, or web,  71  and a far section, or flange,  73 , into which outer journals of the rolls  33  and  35  may be passed to provide overall greater support for the rolls. The arrangement, therefore, provides a channel  77  to support each hand tread. The inside section, or flange,  75  of these channels  77  is still mounted on the support plates  27  and  27   a  in the same manner as the adjustment plates  53  in FIG. 3 so that the treads may be adjusted either up and down or their inclination may be adjusted as explained with respect to FIG.  3 . However, FIG. 4 depicts a much sturdier arrangement of the mechanical aspects of the apparatus. FIG. 4 also shows a further unitary construction, wherein the base plate  11  shown in FIGS. 1,  2  and  3  is part of a larger channel  79  which comprises the base  11 , indicated here as  81 , as well as the two sides  83  and  85 , which constitute the equivalents of the two support plates  27  and  27   a.    
     FIG. 5 is a partially broken-away figure showing an alternative arrangement for construction of an adjustable foot treadmill apparatus. Shown is a side support plate  13  supporting the boom  15  and extending down to the base  11 . Shown partially in phantom and partially broken away are two triangular balancing support members  87  which extend on the outside of the side support plate  13  to add greater stability to the entire apparatus and prevent any possibility of it tipping over to the side. Instead of having the support plate  27  mounted directly against the side support plate  13 , as shown in FIG. 3, in FIG. 5, the support plate  27 , indicated as  27   c,  is mounted upon two brackets  89 , which are attached to the base or inside surface of the base  11 . The side support plate  27   c  is preferably attached to the brackets  89  via jam-type fittings  65  shown in FIG. 3A via the straight slots  63  so that the support plate  27  may be moved upwardly with respect to the brackets  89  to adjust the relative height of the foot tread  51  with respect to the other treads  41   a  and  41   b,  shown in FIG. 5 partially in section or broken off, to establish their relative positions. Meanwhile, an adjustment plate  91  is mounted adjacent to the support plate  27   c  through curved slots  61 , which allow the adjustment plate  91  to be inclined with respect to the support plate  27   c.  Jam-type fittings  65  shown in FIG. 3A will attach the plate  91  to the support plate  27   c  to allow relative adjustment of the two plates and the opposite side of the foot tread  51  will be supported in the same manner as the side shown in FIG.  5 . As will be evident in FIG. 5, it would not be inconvenient for the foot tread  51  to extend all the way across the apparatus, since the feet are relatively close together in their placement upon the ground or a suitable tread, unlike the hand treads  41   a  and  41   b  which need to be fairly wide apart. 
     FIG. 6 shows a further diagrammatic view of the generalized adjustment arrangement shown in the other drawings and particularly FIG. 5 in which an outer support plate  27   c  is provided with straight slots  63  in which a jam-type fitting  65  is placed. The support plate  27   c  may be moved upwardly or downwardly with respect to an outer frame such as, for example, the side support plate  13  or the brackets  89  as shown in FIG.  5 . In FIG. 6 there is also shown an adjustment plate  91  which is held contiguous to the support plate  27   c  by further jam-type fastenings  65  in slots  61  which are curved slots allowing the adjustment plate  91  to be inclined with respect to the support plate  27   c.  There is preferably a pivot  93  in the center of the adjustment plate  91  about which the plate  91  can be pivoted, as allowed by the curved slots  61 . Such pivot arrangement more securely fastens the adjustment plate  91  to the support plate  27   c  while allowing the adjustment plate to be pivoted any desired angle with respect to the support plate and allows either the hand treads or the foot treads to be inclined at any desired angle to either increase or decrease the force necessary to exert upon the treads to turn them or the exercise involved in keeping up with their movement, if the treads are motor driven. It will be noted that the embodiment of adjustment arrangement shown in FIGS. 5 and 6 include a vertical adjustment by vertical adjustment of support plate  27   c,  and adjustment plate  91  is arcuately adjustable on the support plate, while in the embodiment of FIG. 3, the adjustment plates  53 ,  55 ,  57  and  59  are both vertically and arcuately adjustable on stationary support plates  27 . 
     FIG. 7 shows a further alternative embodiment of the invention in which the support plate  27   c  is supported on two pins of a fitting  95  which is disposed on the rear surface of the side support plate  13 , not shown, but as shown in FIG. 5, and has an adjustment screw  101  passing through the center for contact with a lower flange member  27   b  on the side of the side support plate  13 . The adjustment screw  101  may be rotated through handle  103 . A flange member  97  having an L-shape extends from the side of the fitting  95  and is adapted to pass through a slot, not shown, in the side support plate  13 , which is also not shown, in FIG. 7, but is shown in FIG. 8 with the inside of the fitting  95  shown in phantom attached to the rear of the support plate  13  by a bracket, not shown, with the flange  97  extending through a slot  105  in the plate  13 . The adjustment screw  101  will be understood to pass in a screw threaded arrangement with the bracket, not shown, so that when the adjustment screw  101  is rotated, the entire fitting  95  is moved either upwardly or downwardly upon the support plate  13 . The flange  97 , which extends through slot  105  in side support plate  13  shown in phantom has two pins  99  on its outer surface, which pins are extended through a straight slot  63  in the surface of the outer support plate  27   c.  It will be understood that the pins  99  will have on their ends jam fittings or securing means, not shown, which may be jammed against the surface of the plate  27   c  in order to hold such plate at any given height or position on the pins  99 . When the fitting  95  is moved up and down by means of the screw threaded adjustment screw or member  101 , the pins  99  on the flange  97  are also moved up and down, and if the support plate  27   c  is attached by jam-type fastenings  65  upon the pins  99  to the flange  97 , the support plate  27   c  will also be moved up and down. Furthermore, since the support channel  77  is pivoted at  93  to the support plate  27   c,  loosening of similar jam-type adjustment fittings  65  on screw threaded members  102  in the curved slots  61  will enable the entire support channel  77  to not only be adjusted in height but also to be inclined at various angles so that the hand treads  41   a  and  41   b  will also be inclined. Consequently, it will be seen that the construction shown in FIGS. 7 and 8 enables the hand treads to be moved upwardly and downwardly to any desired position by merely turning the knob  103  of the adjustment screw  101 , as well as inclined to any angle about the pivot  93 . 
     FIG. 8 diagrammatically shows the arrangement of FIG. 7 with the support plate  27   c  shown in phantom rather than the side support plate  13  which is shown in FIG. 8 in full outline with the flange  97  of the fitting  95  extending through the slot  105  so that the flange is positioned on the inner side of the support plate  13  in a position such that the pins  99  may fit through a further slot  63  in the support plate as indicated in FIG. 27 c.  The slot  105  provided in the side support plate  13  enables the fitting  95  to be easily moved up and down by means of the screw mechanism  101  to any preferred position within the length of the slot  105 . It will be noted in FIG. 8 that the use of the arrangement shown provides additional up-and-down adjustment since there are two slots, the first slot  105  in the side support plate  13  and the second straight slot  63  in the support plate  27   c.  FIG. 8 shows a slightly different embodiment than FIG. 7 in that instead of threaded member  99  upon which the jamb nuts  69  as shown in FIG. 3A and 6 may be threaded being mounted on flange  97  and extending through a slot  63  in the support plate  27   c,  the threaded members  99  are mounted upon the support plate  27   c  and extend through a slot  63  in the flange  97  which passes over the end of the support plate  27   c.  The result is the same as jamb nuts  69  when mounted upon the threaded members  99  whether mounted upon support plate  27   c  or flange  97  tightly tie the two members together. The adjustment of the support plate  27   c  with respect to the side support plate  13  is in both cases the same by the adjusting screw  101  while the adjustment within the slot  63  is by means of loosening and tightening the jam fittings  65 , not shown, upon the pins  99 . However, apparatus associated with the slot  63  might also be equipped with a screw-type adjustment so that adjustment at the slot  63  might also be made by means of a screw-type fitting. It will also be understood that rather than having two adjustment slots  63  and  105 , either one of those slots could be lengthened to provide additional adjustment, provided that the structure in which the slot is positioned is wide enough to provide a longer slot. The arrangement shown specifically either FIG. 7 or in FIG. 8 provides additional adjustment over that which can be obtained by only one slot, particularly if the structures in which the slots occur are not particularly wide. 
     FIG. 9 shows a detail of the adjustment screw  101  and its rotating head  103  with the screw mounted in the one flange of the fitting  95 , not shown, in the bottom of the screw extending into a seat in a bottom flange  107  of the apparatus. 
     FIG. 10 shows a further detail of the arrangement shown in FIGS. 8 and 9 with a somewhat different fitting  95   a,  one flange  97   a  of which extends through the slot  105  in a side support plate  13  which could also be a slot in a basic support plate  27   c.    
     FIG. 11 is an enlarged detail of the alternative embodiment of the fitting  95   a  shown in FIG. 10 with the flange  97   a  passing through the slot  63  in the support plate  13  with the side support plate  13  shown in phantom as in FIG.  7 . 
     FIG. 12 is an enlargement of an improved arrangement of a mounting for the boom  15  upon the side support plate  13 , in which a boom support plate  109  is attached by welding or the like to the base of the boom  15  and braces  25 . The boom support plate  109  has on the rear surface a narrow plate connecting slot plate  111  which connects to a slide plate  113  having a flange  115  at the top through which may be threaded an adjustment screw  117 . The slot plate  111  is adapted to slide in a slot, not shown, in the side support plate  13 , also not shown in FIG. 12, and the adjustment screw  117  and head or handle  121  allow the boom assembly to be slid to position in a slot, not shown, in the support plate  13 , also not shown, the arrangement being more or less similar to that shown for the adjustment mechanics illustrated in FIGS. 8 through 11 for the vertical adjustment of the support plate  27   c.    
     FIG. 13 is a diagrammatic side elevation showing an alternative arrangement of the tread apparatus of the invention from that shown in FIG.  1 . In FIG. 1, the treads for the hands are separate and distinct from the treads for the feet. In FIG. 13, a singular-type tread  119 , forming a continuous loop, is supported by the rolls  121 ,  123 ,  125 ,  127  and  129 . The hands of the user  17  contact the upper section  131  of the tread, while the feet contact the lower section  133  of the tread. 
     FIG. 14 is an isometric embodiment similar to FIGS. 1 and 3, but providing a single hand tread  41 . Jam-type fastenings  65 , shown in FIG. 3A, will be moved upwardly or downwardly in the straight slots  63  in the support plates as in FIG. 3, thus adjusting the relative heights of the two treads  41  and  51 . If it is desired to slant the tread surfaces  41  or  51  from one end to the other so that one end is higher than the other, only one end of the adjustment plates  53 ,  55 ,  57  or  59  will be moved in an arc corresponding to the curvature of the curved slots  61 . Rounded off lower edges or corners  62  allow the adjustment plates  53  to be moved arcuately without jamming against the bottom plate  11 . 
     FIG. 15 shows a diagrammatic representation of an alternative embodiment of the invention, in which instead of the user of the apparatus being partially supported and suspended from a centralized boom which, while it may be adjustable height-wise is not adjustable longitudinally, instead uses a boom arrangement that may adjust at least somewhat or partially to longitudinal movement. In the embodiment shown in FIG. 15, which is otherwise closely similar to FIG. 14, the boom is pivoted at its base upon a pivot pin  135  mounted in any suitable manner on a base  25   a.  The pivoting arrangement allows the boom  15   a  to swing horizontally to adjust somewhat to longitudinal movement of the quadrupedally exercising user of the apparatus. At the same time the support belt  19  is attached to a ring  137  which may slide over the outer end of the boom  15   a  which, to facilitate such sliding, has been made to have a round configuration  139  rather than the rectangular configuration shown in the preceding drawings. The advantage of the arrangement is that if the one using the apparatus either speeds up or slows down on the treads as shown in previous figures, they will either progress forwardly on the treads or be carried rearwardly upon the treads, and as they progress away from directly under the stationary boom, will tend to be lifted upwardly by the effectively shortened suspension means and belt so that the user looses firm contact with the tread and may even swing momentarily in the air above the treads. With the arrangement shown in FIG. 15, however, there is at least some adjustment possible as the boom  15   a  and the ring  137  on the cylindrical section  139  of the end of the boom swings or slides to follow the user&#39;s movement. A desirable short adjustment range for the suspension belt, while still providing a reliable suspension, is therefore attained. 
     FIG. 16 shows an alternative embodiment of the invention, where instead of a swinging boom  15   a  as shown in FIG. 15 there is instead a slightly inclined transverse supporting bar  141  suspended longitudinally over the treads from two brackets  143   a  and  143   b  at either end of such slightly inclined bar. Since a slow quadruped will tend to be carried backwardly on the apparatus, the longitudinal bar  141  is preferably slightly inclined upwardly to the rear so there is more resistance to movement to the rear than forwardly. The belt  19  is as in FIG. 15 supported from the bar  141  by a sliding ring  137  similar to that shown on the boom  15   a  in FIG. 15, but in FIG. 16 slidable along the supporting bar  141  to accommodate longitudinal movement of the user of the quadruped exercising apparatus of the invention. As will be seen, the side support plate  13  is in FIG. 16 also extended laterally along the top as extension  13   a  to accommodate the two brackets  143   a  and  143   b  on lateral extensions  13   a  of support plate  13 . 
     The use of the two alternative suspensions of the quadruped exerciser shown in FIGS. 15 and 16 provide considerably more flexibility in partially supporting the user of the apparatus while not lifting such user from their feet if the apparatus carries them beyond their normal limits of movement due to momentary tiredness, tripping or the like particularly in or on a powered apparatus. It should also be understood that while it is preferred to use the belt support to take a certain degree of stress from the joints of the user, that it is not necessary to use such belt arrangement either in the form shown in FIGS. 1,  2 ,  3 ,  13 ,  14  or in FIG. 15 or FIG. 16 as the apparatus of the invention can perfectly well be used without the belt support especially by young vigorous, athletically inclined adults. 
     It will be understood from the foregoing description that a very effective structure for an apparatus for exercising the human body by means of a quadrupedal motion has been provided by the present inventor. Various ways of implementing the concept of the invention into specific embodiments have been shown. Furthermore, other embodiments of the invention are possible. 
     One very desirable arrangement would be to have a range of adjustment whereby the hand treads could be brought upward a sufficient distance so that the position of the hand treads would be essentially adjacent to the body forming a bipedal stance rather than the position of the hand treads being at the front end of the body in a quadruped stance. In such an arrangement, modifications in the tread surface would also be desirable so that instead of having the hand “walk” on the surface of the tread, the hand would grasp handholds on the surface of the tread and either pull the tread to the rear or be moved with the tread by a motor to the rear. In manual operation, it would be desirable to incorporate a resistance on the tread thereby increasing the exercise value of pulling the tread while the legs are walking forward on the foot tread. One way that the hand treads could be brought into a semi or completely upright position would be to have a series of curved grooves allowing the entire hand support to be raised upwardly. Alternatively, the entire hand construction could be mounted upon a lever arrangement which could be brought to any position from basically level with the rear foot tread to vertical with respect to the rear foot tread. In this way, the apparatus can be made convertible from a quadrupedal exercise device to a bipedal exercise device and thereby add to its versatility. 
     For example, in a quadrupedal exercise mode, the device is particularly useful for children and young people, as well as persons who require a relatively great amount of exercise with as little strain as possible. While in a bipedal mode, the apparatus is more useful for those adults who merely wish to walk or run in a bipedal mode rather than being placed in what may be a rather unusual and possibly awkward position. However, as indicated above, the fact that the apparatus is arranged so that the foot treads are lower than the hand treads, so that the body of the user is brought substantially into a horizontal position or even somewhat greater than a horizontal position, is sufficient to make the apparatus comfortable for at least the normally athletically inclined person. It will also be recognized that the apparatus of the invention may be made in a number of other embodiments, some of which have been described in the foregoing description. However, it will be readily recognized that the principal important element of the invention is to provide at least two separate treads, one of which takes a higher position than the other, and can be adjusted so that when a human assumes a quadrupedal stance upon the two treads, the body of the person will be substantially horizontal or somewhat greater than horizontal rather than otherwise. As pointed out above, it is convenient to have the hand treads divided into two separate treads, not only because they are spaced fairly widely in accordance with the fairly wide spacing of the shoulders of the human body, but also so that the two hands may operate substantially independently. So far as taking a walking stance is concerned, it is advantageous to move the hands in a coordinated manner with the feet so that the speed of all the treads should be about the same. While individual motors have been shown in the diagrammatic view of FIG. 2 for operation of the treads where motor operation is used, it will be understood also that various coordinated tread operating systems may be used in which only one motor may be necessary, as might appear in FIG.  13 . The motors may be electric, hydraulic or of some other suitable type. 
     In operation or use of the apparatus shown, the height of the hand treads and of the foot tread will be adjusted to the particular anatomy of the individual who will be using the apparatus, so that the person taking a quadrupedal stance will have their body held substantially in a horizontal position or slightly greater than horizontal, designated as the “angle of comfort,” and will then take coordinated steps on the hand treads as well as the foot treads which would, if they were on a natural surface, cause them to move along in a coordinated manner in a quadrupedal stance. 
     It will be understood that while a particularly effective apparatus has been shown in the accompanying drawings and claimed in the accompanying claims to practice this sort of exercise, that various other arrangements to effect a similar exercise routine could be conceivably constructed. For example, rather than having a bipartite endless tread surface, a track for quadrupedal exercise locomotion could be constructed having a two-level surface in which the feet of the user would progress along one level in the center and the hands of the user supporting the upper portion of the body could progress along a higher level, the two levels being coordinated such that when the user is progressing in a quadrupedal pace along the track, the body of the user is disposed substantially horizontally. The track could be constructed either by having a simple trench provided in the surface of the ground having a depth sufficient so that the legs would be brought to a depth which would match the hands progressing along the surface of the ground, or as an alternative, a completely depressed track could be provided in which there are two levels, one for the legs and one for the hands. As a still further alternative, the legs could progress along the normal surface of the earth and the hands could progress along two built-up portions beside the legs. In a similar manner, an endless tread could be constructed having two levels, the lower level for the feet and the upper level for the hands, the two levels again being spaced a distance apart so that the body would assume essentially a horizontal position during the exercise (see FIG.  13 ). As a still further embodiment, two separate endless treads could be arranged to run past a point at which the user was to be exercising, the upper tread which would be in a bipartite form with one half on each side being at a level suitable for the hands in a quadrupedal exercise stance and the inside tread being at a level suitable for supporting the feet in the quadrupedal exercise stance. 
     Exercise as described, therefore, can be practiced in several manners other than with the exact apparatus described in this application for patent. Furthermore, no matter how the particular quadrupedal walking or running is effected, the one exercising is automatically obtaining a very thorough, all-inclusive exercise of many body parts with very little strain to any given part, since the weight of the user is distributed over four support points rather than the two support points normally used in bipedal running and walking. Consequently, the quadrupedal exercise mode is particularly suitable for persons who might otherwise injure themselves due to a continuous repetitive pounding upon a track or the like. Furthermore, the use of the support belt about the midriff of the user in the preferred embodiment of the invention relieves some of the weight from the hands and feet of the user and also stabilizes the position of the user with respect to the moving treads. 
     The present inventor, therefore, has provided not only a new and effective apparatus for providing a completely new and unusually effective exercise of the body parts, but has also developed a new method of exercising which can be effected in various ways, including the use of the particular apparatus shown and described in this application for patent. Running or walking in a quadrupedal stance has not been unknown to children who may gain considerable pleasure by pretending they are animals. Such a mode of movement provides unexpected benefits to the physiology of the human animal with respect to exercise of the muscles in a persistent yet gentle exercise mode. There is also a certain satisfaction in the movement once it is established, which satisfaction can be attributed only to some atavistic memory of ancient four-legged movement, even before the evolution of our ancestors into forms adapted for progression from branch to branch in the trees. 
     The angle of comfort, i.e. the angle at which comfortable quadrupedal locomotion along a track, treadmill or other arrangement for quadrupedal movement of humans is effected, is from approximately parallel to horizontal to not more than about fifteen degrees from parallel to horizontal in a heads-up position. If the angle of the spine is less than this and the hips are elevated significantly more than the shoulders, the position will be uncomfortable. If the angle is greater than this, the walking motion should be considered to be not quadrupedal exercise, but bipedal exercise and may also be desirable, especially if the apparatus is designed for interconvertibility. 
     While the present invention has been described at some length and with some particularity with respect to the several described embodiments, it is not intended that it should be limited to any such particulars or embodiments or any particular embodiment, but it is to be construed with references to the appended claims so as to provide the broadest possible interpretation of such claims in view of the prior art and, therefore, to effectively encompass the intended scope of the invention.