Abstract:
A method of using an adjustable user support platform with an inclinable exercise device includes providing an adjustable user support platform movably attached to an adjustable incline of the inclinable exercise device for movement of the adjustable user support platform along the adjustable incline, the adjustable user support platform including a support platform frame with a support platform and a support frame, the support platform frame operably coupled to the support frame for adjustably inclining the support platform frame with support platform relative to the support frame; inclining the support platform frame with the support platform relative to the support frame to a desired tilt angle; and securing the support platform frame with the support platform at the desired pivot angle relative to the support frame.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a Continuation-In-Part of co-pending application Ser. No. 12/551,662 filed on Sep. 1, 2009, which claims the benefit of provisional patent application 61/094,586, filed Sep. 5, 2008 under 35 U.S.C. 119(e), and each of the aforementioned patent applications is incorporated by reference herein as though set forth in full. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to an exercise device. More particularly, the present invention relates to an adjustable user support platform for inclinable exercise device wherein the exerciser exerts muscle force against an adjustable portion of the exerciser&#39;s own body weight. 
     BACKGROUND OF THE INVENTION 
     Inclinable exercise devices such as that shown in U.S. Pat. No. 5,967,951 in which an exerciser exerts muscle force against an adjustable portion of the exerciser&#39;s own body weight have been developed. The inventors of the present invention have recognized that it would desirable to develop a user support platform for such an exercise device that allows the exerciser to maintain neutral spine position and proper posture during exercise, achieving a safer and more functional result. 
     SUMMARY OF THE INVENTION 
     An aspect of the invention involves an adjustable user support platform for an inclinable exercise device. The inclinable exercise device includes a vertical support member, and first and second sets of rails each having a first end and a second end. The first ends of the first set of rails are pivotally connected to, and adjustably supported by, the vertical support member. The first ends of the second set of rails are connected to the second end of the first set of rails. A strut includes a first end pivotally connected to the vertical support member and a second end pivotally connected to the rails. The adjustable user support platform includes a support surface that can be pivoted and fixed in a variety of different angles. The pivotal user support platform allows the exerciser to maintain neutral spine position and proper posture during exercise, achieving a safer and more functional result. 
     Another aspect of the invention involves a method of using an adjustable user support platform with an inclinable exercise device. The inclinable exercise device includes a vertical support member; an adjustable incline having a first end and a second end, the first end of the adjustable incline adjustably supported by, and vertically movable with respect to, the vertical support member for adjusting the incline of the adjustable incline. The method includes the steps of providing, based on user input, an adjustable user support platform movably attached to the adjustable incline for movement of the adjustable user support platform along the adjustable incline, the adjustable user support platform including a support platform frame with a support platform, and a support frame, the support platform frame operably coupled to the support frame for adjustably inclining the support platform frame with support platform relative to the support frame; inclining, based on user input, the support platform frame with the support platform relative to the support frame to a desired tilt angle; securing, based on user input, the support platform frame with the support platform at the desired pivot angle relative to the support frame. 
     One or more implementations of the aspect of the invention described immediately above include one or more of the following: receiving a user&#39;s torso against the support platform at the desired pivot angle relative to the support frame; and moving, based on user input, one&#39;s torso supported by the support platform and the adjustable user support platform along the adjustable incline; the support platform frame and the support frame define respective planes and further including movably adjusting, based on user input, the support platform frame relative to the support frame so that the plane defined by the support platform frame is substantially coplanar with the frame defined by the support frame; the adjustable user support platform includes a tilt angle adjustment mechanism, the support platform frame adjustably supported by the tilt angle adjustment mechanism for adjusting the tilt angle of the support platform frame with support platform relative to the support frame, and the method further includes adjusting, based on user input, the tilt angle of the support platform frame with support platform relative to the support frame; the support platform frame includes an upper end and a lower end, the upper end located closer to the vertical support member than the lower end, the lower end of the support platform frame adjustably supported by the tilt angle adjustment mechanism for adjusting the tilt angle of the support platform frame with support platform relative to the support frame, and the method further includes adjusting, based on user input, the tilt angle of the support platform frame with support platform relative to the support frame; at least one of the support platform frame and the support frame including support stops therein and the tilt angle adjustment mechanism includes a retractable support mechanism that is positionable at the support stops for adjusting the tilt angle of the support platform frame with support platform relative to the support frame, and the method further includes positioning, based on user input, the retractable support mechanism at one of the support stops to set the tilt angle of the support platform frame with support platform relative to the support frame; the tilt angle adjustment mechanism includes a screw-type tilt angle adjustment mechanism that is rotatably adjustable for adjusting the tilt angle of the support platform frame with support platform relative to the support frame, and the method further includes rotatably adjusting, based on user input, the screw-type tilt angle adjustment mechanism to set the tilt angle of the support platform frame with support platform relative to the support frame; the screw-type tilt angle adjustment mechanism provides infinite tilt angle adjustment, and the method includes rotatably adjusting, based on user input, the screw-type tilt angle adjustment mechanism to set the tilt angle at a tilt angle of an infinite possible tilt angles; and/or the support platform frame includes an upper end and a lower end, the upper end located closer to the vertical support member than the lower end, the support frame includes an upper end and a lower end, the upper end located closer to the vertical support member than the lower end, and the upper end of the support platform frame is pivotally coupled to the upper end of the support frame. 
     A further aspect of the invention involves an adjustable user support platform for an inclinable exercise device, the inclinable exercise device including a vertical support member; an adjustable incline having a first end and a second end, the first end of the adjustable incline adjustably supported by, and vertically movable with respect to, the vertical support member for adjusting the incline of the adjustable incline; including a support frame including an upper end and a lower end, the upper end located closer to the vertical support member than the lower end; a support platform frame including an upper end and a lower end, the upper end located closer to the vertical support member than the lower end, the support platform frame including a support platform, the support platform frame operably coupled to the support frame for adjustably inclining the support platform frame with support platform relative to the support frame, the support platform configured to receive a user&#39;s torso for supporting a user of the inclinable exercise device; and a tilt angle adjustment mechanism adjustably supporting the support platform frame relative to support frame for adjusting the tilt angle of the support platform frame with support platform relative to the support frame. 
     One or more implementations of the aspect of the invention described immediately above include one or more of the following: the support platform frame and the support frame define respective planes, and support platform frame is movable relative to the support frame to position the support platform frame so that the plane defined by the support platform frame is substantially coplanar with the frame defined by the support frame; at least one of the support platform frame and the support frame includes support stops therein and the tilt angle adjustment mechanism includes a retractable support mechanism that is positionable at the support stops for adjusting the tilt angle of the support platform frame with support platform relative to the support frame; the tilt angle adjustment mechanism includes a screw-type tilt angle adjustment mechanism that is rotatably adjustable for adjusting the tilt angle of the support platform frame with support platform relative to the support frame; and/or the upper end of the support platform frame is pivotally coupled to the upper end of the support frame. The tilt angle adjustment mechanism may alternatively include one or more lockable gas struts pivotally mounted between the support frame and support platform that are adjustable in length for adjusting the tilt angle of the support platform frame. 
     A still further aspect of the invention includes an inclinable exercise device including a vertical support member; an adjustable incline having a first end and a second end, the first end of the adjustable incline adjustably supported by, and vertically movable with respect to, the vertical support member for adjusting the incline of the adjustable incline; and an adjustable user support platform movably attached to the adjustable incline for movement of the adjustable user support platform along the adjustable incline. The adjustable user support platform having a support frame including an upper end and a lower end, the upper end located closer to the vertical support member than the lower end; a support platform frame including an upper end and a lower end, the upper end located closer to the vertical support member than the lower end, the support platform frame including a support platform, the support platform frame operably coupled to the support frame for adjustably inclining the support platform frame with support platform relative to the support frame, the support platform configured to receive a user&#39;s torso for supporting a user of the inclinable exercise device; and a tilt angle adjustment mechanism adjustably supporting the support platform frame relative to support frame for adjusting the tilt angle of the support platform frame with support platform relative to the support frame. 
     It is understood that both the foregoing general description and following detailed description are exemplary and explanatory and are intended to provide further explanation to the invention as claimed. The accompanying drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate several embodiments of the invention and together with the description serve to explain the principles of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and, together with the description, serve to explain the objects, advantages, and principles of the invention. In the drawings, 
         FIG. 1  is a top plan view of an embodiment of an inclinable exercise device including a pivotal user support platform shown disposed in its “normal” orientation; 
         FIG. 2  is a front perspective view of the inclinable exercise device shown in  FIG. 1 ; 
         FIG. 3  is a left side-elevational view of the inclinable exercise device shown in  FIG. 1 ; 
         FIG. 4  is a rear perspective view of the inclinable exercise device shown in  FIG. 1 ; 
         FIG. 5  is a top plan view of an embodiment of an inclinable exercise device including a pivotal user support platform shown disposed in its “angled” orientation; 
         FIG. 6  is a front perspective view of the inclinable exercise device shown in  FIG. 5 ; 
         FIG. 7  is a left side-elevational view of the inclinable exercise device shown in  FIG. 5 ; 
         FIG. 8  is a rear perspective view of the inclinable exercise device shown in  FIG. 5 . 
         FIG. 9  is an exploded perspective view of an embodiment of the pivotal user support platform. 
         FIG. 10  is a top plan view of the pivotal user support platform of  FIG. 9 . 
         FIG. 11  is a perspective plan view of the pivotal user support platform of  FIG. 9 . 
         FIG. 12  is a front elevational view of the pivotal user support platform of  FIG. 9 . 
         FIG. 13  is a right side elevational view of the pivotal user support platform of  FIG. 9 . 
         FIG. 14  is a perspective view of an alternative embodiment of a pivotal user support platform, and shows the pivotal user support platform in a fully raised/tilted configuration. 
         FIG. 15  is a perspective view of the pivotal user support platform of  FIG. 14 , and shows the pivotal user support platform in a fully compacted/flat configuration. 
         FIG. 16  is an exploded perspective view of the pivotal user support platform of  FIG. 14 . 
         FIG. 17  is a perspective view of another alternative embodiment of the pivotal user support platform to replace the pivotal user support platform on the inclinable exercise device of  FIG. 1 , and shows the user support platform in a raised or tilted configuration. 
         FIG. 18  illustrates the locking mechanism for the telescoping gas strut of  FIG. 17  in the locked position. 
         FIG. 19  illustrates the locking mechanism of  FIG. 18  in the released position. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     With reference to  FIGS. 1-3 , an embodiment of an inclinable exercise device  100  includes an adjustable, pivotal, tiltable user support platform  105 . Before describing the pivotal user support platform  105 , the inclinable exercise device  100  will be generally described. 
     The inclinable exercise device  100  includes a vertical support member or tower  110  having a base  120  and a tower housing  130 . The base  120  includes a pair of opposite foot-shaped base members  140  joined by an intermediate base section  150 . 
     The tower housing  130  extends from the intermediate base section  150  of the base  120 . The tower housing  130  includes a motorized lift mechanism to lift and lower (and adjust the angle of) the collapsible exercise device  100 . In alternative embodiments, the collapsible exercise device  100  includes a non-motorized lift assist mechanism or no lift assist mechanism for assisting the user in adjusting the angle/inclination of the collapsible exercise device  100 . 
     A pair of upper rails  250  are connected to lower rails  240 . A strut (or struts_ 260  is/are pivotally connected to the base  120  and is also pivotally connected to the rails  250 ,  240  at rail pivot points  230 . The rails  250 ,  240  support the slidable/movable pivotal user support platform  105 . 
     A folding squat platform  360  is shown in an unfolded state. The folding squat platform  360  includes opposite parallel rails  370  joined by perpendicularly extending cross rail  380 . A pivot portion  390  carries a spring-loaded pull pin  410  for locking the folding squat platform  360  within a pin hole near a distal end of the lower rails  240 . 
     Folding, combination pulley-support and pull-up bars  830  are respectively pivotally connected to mounting mechanisms  385  at proximal ends  220  of the upper rails  250 . The mounting mechanisms  385  move up and down with the motorized lifting mechanism for raising and lowering the rails  240 ,  250 . Each bar  830  has a trapezoidal configuration. For normal use, the bars  830  may be moved to the position shown in  FIGS. 1-6 . For performing chin ups and related exercises, the bars  830  may be moved to a position where the bars  830  are generally parallel with the rails  240 ,  250 . 
     Pulleys  940  are slidably attached to the bars  830 . An exerciser may move each pulley  940  to a desired position on the bar  830 . 
     A connector extends through the pulleys  940  and connects to the pivotal user support platform  105 . The connector may be of any suitable well-known type, but is preferably a cable. The cable includes handles (connected via links) at each end and extends through the pulleys  940  positioned on the combination pulley-support and pull-up bars  830  and loops through a third pulley attached to the pivotal user support platform  105 . The third pulley is positioned along the lateral centerline of the pivotal user support platform  105 . This position allows for unilateral (i.e. one arm), bilateral (i.e., two arm) and static equilibrium (i.e. holding the pivotal user support platform  105  suspended by keeping a constant force on each handle) use. The cable should preferably be of sufficient length to extend through the pulleys  940  and allow the exerciser to grasp one or both of the handles while the exerciser is on the pivotal user support platform  105  and the pivotal user support platform  105  is at rest. 
     In an alternate embodiment, the connector may be two separate cables extending through the pulleys  940  with each cable fixedly attached to the pivotal user support platform  105 . 
     With reference to  FIG. 9 , the pivotal user support platform  105  will now be described in more detail. The pivotal user support platform  105  includes a support frame  350  and a glide board/support platform frame  351  pivotally connected to the support frame  350  at adjacent ends via a pivot mechanism. The pivot mechanism includes pivot pins  352  disposed through holes in the adjacent ends of the support frame  350  and the glide board frame  351 . 
     The support frame  350  includes elongated parallel longitudinal rails  353 , and a pair of transverse rails  354  (one of which includes hook member  361 ) connecting the longitudinal rails  353 . Near opposite ends of the longitudinal rails  353 , rollers  355  are provided for rolling movement of the pivotal user support platform  105  on the rails  240 ,  250 . Along an inner side of the transverse rails  353 , a notched groove  356  with multiple support notches  357  are disposed. 
     With reference to  FIG. 10 , the glideboard frame  351  includes elongated parallel longitudinal rails  358 , and upper brackets  362  and a lateral bracket  363  attached to the elongated parallel longitudinal rails  358 . A tilt angle adjustment mechanism in the form of a retractable support mechanism  344  is pivotally attached to the elongated parallel longitudinal rails  358  and the lateral bracket  363 . 
     With reference to  FIG. 913 , the retractable support mechanism  344  includes parallel support rails  364  connected at an end by a support bar  365 . The support rails  364  are pivotally connected to the elongated parallel longitudinal rails  358  and the lateral bracket  363  via pivot pins  359 . 
     A main support pad/support platform  366  is attached to and supported by the glideboard/support platform frame  351 . A bumper (not shown) may be positioned on the lower rails  240  to prevent the pivotal user support platform  105  from rolling all the way down the lower rails  240 . 
     In use, the exerciser positions himself or herself on the pivotal user support platform  105  and grasps one or both of the handles. The exerciser then draws one or both of the handles toward the exerciser and by doing so transports the pivotal user support platform  105  up along the lower rails  240  and upper rails  250 . 
     Using the motorized lift mechanism, the height of the proximal ends  220  of the upper rails  250  (via the mounting mechanisms  385 ) are raised and lowered, varying the angle of inclination of the rails  250 ,  240 . The adjustment of this angle of inclination alters the percentage of the exerciser&#39;s weight which the exerciser&#39;s muscles are moving. This allows for adjustment of the intensity of the exerciser&#39;s workout. 
     An exerciser may also vary the resistance while working upper body muscles by positioning him or herself on the pivotal user support platform  105  with the exerciser&#39;s feet on the squat stand  350  or floor. The legs and lower body then provide assistance in moving the pivotal user support platform  105 , lessening the load on the upper body muscles. The exerciser may also use the squat stand  360  to perform the squat exercise for the lower body muscles. 
     The exerciser may adjust/move the tilt angle of the pivotal/tiltable user support platform  105  by pivoting/tilting the glideboard frame  351  and the main support pad  366  (about pivot pins  352 ) relative to the support frame  350 . The angle of the glideboard frame  351  and the main support pad  366  relative to the support frame  350  is locked into place at the desired tilt angle using the retractable support mechanism  344  (the support bar  365  is set in the appropriate notches  357 ). Setting the support bar  365  in the different notches  357  allows for 4, 8, 10, 12, 14, and 16 degrees of tilt relative to the support frame  350 . With the glideboard frame  351  and the main support pad  366  pivoted upwards relative to the support frame  350 , the retractable support mechanism  344  at the bottom/lower end of pivotal user support platform  105  is pivoted/moved between a “normal” retracted orientation (where a plane defined by the glideboard frame  351  and a plane defined by the support frame  350  are substantially parallel and substantially coplanar and the support bar  365  is fully disposed inwardly, toward center of glideboard frame  351  (in the notched groove  356 ) to a “supported” position ( FIGS. 11 ,  12 ) where the glideboard frame  351  and the main support pad  366  are supported at an angled orientation relative to the support frame  350  (the support bar  365  is set in the appropriate notches  357 ). 
     To return the pivotal user support platform  105  to the “normal” retracted orientation, the glideboard frame  351  and the main support pad  366  are pivoted upwards relative to the support frame  350  (so that the support bar  365  is no longer engaged/locked in the notches  357 ), and the retractable support mechanism  344  at the bottom/lower end of pivotal user support platform  105  is pivoted/moved from the “supported” position, where the support bar  365  is engaged/locked in the notches  357 , to the “retracted” position (where the support bar  365  is fully disposed inwardly, toward center of glideboard frame  351 , in the notched groove  356 ). The glideboard frame  351  and the main support pad  366  are then pivoted/lowered to a “normal” orientation, where the glideboard frame  351  and the support frame  350  are substantially parallel and substantially coplanar. 
     In an alternative embodiment, the notches  357  are disposed in the glideboard frame  351  and the retractable support mechanism  344  is pivotally coupled to the end of the support frame  350 , enabling the pivotal user support platform  105  to work in a similar, but opposite, manner compared to that described above. 
     The pivotal user support platform  105  allows the exerciser to maintain neutral spine position and proper posture, which is important during rotating exercises. The pivotal user support platform  105  makes it easier for the exerciser to maintain correct posture during certain exercises, achieving a safer and more functional result. 
     For neurological patients, the pivotal user support platform  105  allows them to sit on a horizontal carriage while relearning motor skills, training the proprioceptors and gaining increased proprioceptive response, needed for stability and agility. For patients rehabilitating from a stroke, the pivotal user support platform  105  also makes is easier for them to get on and off the exercise device. 
     With reference to  FIGS. 14-16 , an alternative embodiment of a pivotal user support platform  505  that provides infinite tilt adjustment (i.e., infinite tilt angles) between 0 degrees and 18 degrees will be described. The infinite adjustment pivotal user support platform  505  includes a tilt angle adjustment mechanism in the form of a screw-type tilt angle adjustment mechanism  510 . The screw-type tilt angle adjustment mechanism  510  includes a screw block  520  with a threaded interior bore that threadably receives an externally threaded screw shaft  525 . A proximal portion of the screw shaft  525  is rotatably disposed in a hole of transverse rail  359   a , and the screw shaft  525  is in the same plane as a plane defined by support frame  350   a  (and parallel with longitudinal rails  353   a  of the support frame  350   a ). A proximal end of the screw shaft  525  includes a hand crank  530 . In an alternative embodiment, the tilt angle adjustment mechanism  510  includes a remote-controlled motorized screw-type tilt angle adjustment mechanism instead of a manually controlled screw-type tilt angle adjustment mechanism. Support bar  365   a  extends laterally through another bore in the screw block  520  and is connected to a bottom of retractable support mechanism  344   a . Opposite ends of the support bar  365   a  are slidably and guidably disposed in smooth guide groove  356   a . In an alternative embodiment, the screw-type tilt angle adjustment mechanism  510  and the groove  356   a  are substantially disposed in the glide board frame  351   a  instead of the support frame  350   a , enabling the pivotal user support platform  505  to work in a similar, but opposite, manner compared to that described above. 
     In use, an exerciser adjusts the tilt angle of the glide board frame  351   a  and the main support pad  366   a  relative to the support frame  350   a  by operating the screw-type tilt angle adjustment mechanism  510 . Clockwise and counter-clockwise rotation of the externally threaded screw shaft  525  via the hand crank  530  causes the screw block  520  to move forward or rearward relative to the longitudinal direction of the support frame  350   a . This causes the bottom of the retractable support mechanism  344   a  to also move forward or rearward with the ends of the support bar  365   a  being guidably disposed in the guide groove  356   a . As the bottom of the retractable support mechanism  344   a  moves longitudinally relative to the support frame  350   a , the top of the retractable support mechanism  344   a  (along with the coupled end portions of the glide board frame  351   a  and the main support pad  366   a ) moves towards or away the support frame  350   a , changing the tilt angle of the glide board frame  351   a  and the main support pad  366   a  relative to the support frame  350   a . The tilt angle of the glide board frame  351   a  and the main support pad  366   a  relative to the support frame  350   a  can be set in an infinite number of tilt angles between a maximum tilt angle (e.g., 18 degrees,  FIG. 14 ) and a minimum tilt angle (e.g., 0 degrees,  FIG. 15 ), where the glide board frame  351   a  and the support frame  350   a  are substantially parallel and substantially coplanar. 
     The infinite adjustment pivotal user support platform  505  provides the exerciser with greater control of tilt angle adjustment than the pivotal user support platform  105 . 
       FIG. 17  illustrates another alternative embodiment of a tiltable user support platform  550  which may be used in place of the tiltable user support platform  105  on the inclinable exercise device of  FIGS. 1 to 8 . Tiltable user support platform  550  is similar to the platforms  105  and  505  apart from the replacement of the retractable support mechanism  344 ,  344   a  and the adjustment mechanism  510  of the previous embodiments with a locking gas strut adjuster  560 , which also provides for continuous adjustment of the tilt angle through the entire range of angles, rather than incremental adjustment between fixed angles as in platform  105 .  FIGS. 18 and 19  illustrate the release mechanism  565  for the locking gas strut adjuster  560  in the locked and released positions, respectively. 
     As in the previous embodiments, the tiltable user support platform  550  basically comprises a base support frame  566  slidably engageable on the rails  240 ,  250  of the inclinable exercise device via rollers  355  at the upper and lower ends of the frame, and a glide board frame  568  pivotally mounted on the base support frame at its upper end via pivot pins  570 . Glide board frame  568  is pivotable between raised, pivoted positions such as the position of  FIG. 17  in which it is at an angle to the base frame and to the upper and lower rails of the inclinable exercise device, similar to user support platform  105  in the position of  FIG. 6 , and a folded flat position in which glide board frame is folded flat over base support frame  566  so that it is at the same angle as the adjustable rails  240 , 250  of the inclinable exercise device, in an equivalent position to the position of the tiltable platform  105  in  FIG. 2 . 
     Base or support frame  566  basically comprises a pair of parallel side rails  572  connected together via upper and lower cross bars  573 ,  574  adjacent its opposite ends. Rollers  355  are also provided adjacent the opposite ends of each side rail for movable engagement on the inclinable rails  240  and  250 . Each of the rails and cross bars of support frame  566  may have a plurality of openings for reduced weight. The lower cross bar  574  has a pair of indented seats  575  adjacent its opposite ends for seating the gas strut adjuster in the folded flat condition, as explained in more detail below. The glide board frame  568  comprises a glide board platform or pad  576  mounted on a base plate  578 , and a pair of parallel side rails  580  depending downwardly from base plate  578 . Side rails  580  are pivotally connected to side rails  572  of the base support frame  566  adjacent their forward ends via pivot pins  570 , as noted above. 
     The tilt angle between frames  566  and  568  is controlled by locking gas strut adjuster  560 . Adjuster  560  basically comprises a pair of parallel locking gas struts  582  each pivoted at one end to a cross bar or sliding guide  584  which is slidably engaged between the opposite side rails  572  of the base support frame. The opposite ends of the gas struts are pivotally connected via pivot bracket  583  to a mounting bracket assembly  585  on the undersurface of base plate  578  adjacent the rear end of the frame  568  via pivot pins  586 . Each gas strut acts as an adjustable length, pivoting link and comprises a cylinder  587  with an extendable piston rod  588  projecting from one end of the cylinder. The gas struts are of the type used on hospital beds and each have a push button  592  at the end of an actuator rod  591  which projects from one end of the strut ( FIGS. 18 and 19 ) and which can be depressed in order to open a valve allowing fluid to flow between the chambers on opposite sides of a piston in cylinder  587 . When the push button is released, rod  591  is biased into an extended position in which the valve is closed, locking the gas strut in a selected extended or retracted position. The release mechanism for operating both gas strut push buttons is illustrated in detail for one of the push buttons  592  in  FIGS. 18 and 19  and is similar to that used for hospital bed adjustment. The mechanism comprises a pair of eccentrically mounted cams  590  which are mounted on mounting assembly  585  for rotation about the same pivot axis as the gas struts. Each cam engages a respective push button and the cams are connected together by handle  594 . When the push button  592  is depressed, an internal valve is opened to allow fluid to leak between opposite ends of the cylinder and the gas strut will slowly extend towards its fully extended condition. Alternative release mechanisms such as a rocking or sliding lever which pushes up and down may alternatively be used. 
       FIG. 18  illustrates the handle  594  in the locked position in which the actuator buttons  592  are in the extended position, and the internal control valve is closed to lock the gas strut. In this cam position, a smaller portion of the eccentrically mounted cam  590  is interposed between the pivot axis and push button. When the handle  594  is rotated upwards into the released position illustrated in  FIG. 19 , the larger portion of each cam is rotated downward and pushes the respective button and associated actuator rod into a depressed position so that the valve is opened and gas can leak from one side of the piston to the other, allowing the lengths of the gas struts to be adjusted so that the glide board platform can be oriented at a larger or smaller angle relative to the base support frame. This allows a user to adjust the platform to the desired angle quickly and easily, simply by gripping and pulling up the handle  594 , adjusting the platform position, and then rotating the handle back down to lock the struts at the desired extension. If the user wishes the glide board platform to rest flat against the base support frame, they simply release the gas struts from the locked position by rotating handle  594  upwardly, then lower the platform down as sliding guide or cross bar  584  slides towards the upper ends of side rails  572  and the glide platform side rails  580  engage over base frame side rails  572 . The piston rods  588  are pushed back into the cylinders, which can be engaged in the recesses  575  in cross bar  574  when the tilt platform is folded flat against support fame  566 . The struts are then locked in position by rotating the handle into the locked position of  FIG. 18 . This arrangement allows the tiltable glide board platform to be readily adjusted to any desired angle. 
     Although the pivotal user support platforms  105 ,  505  and  550 , have been described above as being tiltable between angles of 0 degrees and as much as 18 degrees, in alternative embodiments, the pivotal user support platforms  105 ,  505 , and  550  are tiltable between one or more alternative parameters (i.e., greater and/or less than those indicated). 
     Further, in alternative embodiments, the tilt angle adjustment mechanism includes a different configuration that those described/shown herein. 
     The above figures may depict exemplary configurations for the invention, which is done to aid in understanding the features and functionality that can be included in the invention. The invention is not restricted to the illustrated architectures or configurations, but can be implemented using a variety of alternative architectures and configurations. Additionally, although the invention is described above in terms of various exemplary embodiments and implementations, it should be understood that the various features and functionality described in one or more of the individual embodiments with which they are described, but instead can be applied, alone or in some combination, to one or more of the other embodiments of the invention, whether or not such embodiments are described and whether or not such features are presented as being a part of a described embodiment. Thus the breadth and scope of the present invention, especially in the following claims, should not be limited by any of the above-described exemplary embodiments. 
     Terms and phrases used in this document, and variations thereof, unless otherwise expressly stated, should be construed as open ended as opposed to limiting. As examples of the foregoing: the term “including” should be read as mean “including, without limitation” or the like; the term “example” is used to provide exemplary instances of the item in discussion, not an exhaustive or limiting list thereof; and adjectives such as “conventional,” “traditional,” “standard,” “known” and terms of similar meaning should not be construed as limiting the item described to a given time period or to an item available as of a given time, but instead should be read to encompass conventional, traditional, normal, or standard technologies that may be available or known now or at any time in the future. Likewise, a group of items linked with the conjunction “and” should not be read as requiring that each and every one of those items be present in the grouping, but rather should be read as “and/or” unless expressly stated otherwise. Similarly, a group of items linked with the conjunction “or” should not be read as requiring mutual exclusivity among that group, but rather should also be read as “and/or” unless expressly stated otherwise. Furthermore, although item, elements or components of the disclosure may be described or claimed in the singular, the plural is contemplated to be within the scope thereof unless limitation to the singular is explicitly stated. The presence of broadening words and phrases such as “one or more,” “at least,” “but not limited to” or other like phrases in some instances shall not be read to mean that the narrower case is intended or required in instances where such broadening phrases may be absent.