A cross-training exercise apparatus includes a base, a pair of foot supports pivotally and slidably joined to the base by way of a three-member linkage arrangement interposed between each foot support and the base. Each three-member linkage arrangement accommodates a pivotal movement of a corresponding foot support relative to the base between forward and rearward positions and accommodates a sliding movement of each foot support relative to the base between raised and lowered positions. The exercise apparatus also includes a pair of cable and pulley arrangements which are associated with the base and joined between the foot supports for coordinating the pivotal and sliding movement of the foot supports between forward and rearward positions or between upward and downward positions so that pivotal or sliding movement of one foot support relative to the base effects a corresponding pivotal or sliding movement of the other foot support relative to the base.

BACKGROUND OF THE INVENTION 
This invention relates generally to exercise equipment and more 
particularly is concerned with exercise apparatus which involves the 
movement of two feet of a user in an alternating fashion during use of the 
apparatus. 
For example, one exercise apparatus with which this invention can be 
compared is a stair-climbing apparatus wherein the feet are alternately 
raised from a lowered position so that when one foot is in an elevated 
position, the other foot is in a lowered position, and vise-versa. Another 
exercise apparatus with which this invention can be compared is a 
cycle-type exercise device wherein the feet of a user are used to forcibly 
rotate cranks about a horizontal axis of rotation and the feet are 
positioned at diametrically-opposed locations relative to the axis of 
rotation. Consequently, when one foot of the user forces a corresponding 
pedal of the crank downwardly, the other pedal of the crank lifts the 
other foot of the user upwardly. 
Another exercise apparatus with which this invention can be compared is a 
ski-type exercise device having a frame and a pair of feet-supporting skis 
slidably mounted upon the frame for movement in forward and rearward 
directions relative thereto. During use of the ski-type exercise device, 
one foot of the user is urged rearwardly relative to the frame while the 
other foot of the user is shifted forwardly relative to the frame. 
It is an object of the present invention is to provide a new and improved 
exercise apparatus involving alternating movements of the feet of the user 
during use of the apparatus. 
Another object of the present invention is to provide such an apparatus 
wherein a user may selectively simulate cycling movements, stair-climbing 
movements, skiing movements, running movements or walking movements. 
Yet another object of the present invention is to provide such an apparatus 
for exercising the arms, as well as the legs, of a user during an exercise 
routine. 
Still another object of the present invention is to provide such an 
apparatus which is uncomplicated in construction and effective in 
operation. 
SUMMARY OF THE INVENTION 
This invention resides in an exercise apparatus including a base having a 
front and a pair of foot supports joined to the base in a manner which 
accommodates a movement of each foot support relative to the base between 
forward and rearward positions and accommodates a movement of each foot 
support relative to the base between raised and lowered positions. Means 
are associated with the base and joined between the foot supports for 
coordinating the movement of the foot supports between forward and 
rearward positions so that the movement of one foot support relative to 
the base in one of a forward and rearward direction effects a 
corresponding movement of the other foot support relative to the base in 
the other of the forward and rearward direction and for coordinating the 
movement of the foot supports between raised and lowered positions so that 
movement of one foot support relative to the base in one of a upward and 
downward direction effects a corresponding sliding movement of the other 
foot support relative to the base in the other of the upward and downward 
direction.

DETAILED DESCRIPTION OF THE ILLUSTRATIVE EMBODIMENTS 
Turning now to the drawings in greater detail, there is shown in FIG. 1 an 
embodiment, generally indicated 20, of a cross-training exercise apparatus 
within with features of the present invention are incorporated. The 
embodiment 20 includes a base 22 and a pair of left and right foot 
supports 24 and 26, respectively, which are connected to the base 22 by 
way of linkage assemblies (described herein) so that the each foot support 
24 or 26 is movable relative to the base 22 in a substantially 
vertically-oriented plane to accommodate the movement of the foot support 
24 or 26 through any of a number of positions in that vertical plane. In 
addition, the foot supports 24, 26 are connected to one another so that 
the movement of each foot support 24 or 26 within its vertical plane is 
coordinated with that of the other foot support 26 or 24. For example, as 
one foot support 24 or 26 is forcibly moved downwardly relative to the 
base 22, the other foot support 26 or 24 is forcibly moved upwardly 
relative to the base 22. During use of the apparatus 20, a user stands 
with his feet upon the foot supports 24 and 26 and, while holding onto 
appropriate grips of the apparatus 20, moves his feet (and appropriately 
shifts his weight) to simulate any of a number of exercise motions, such 
as cycling, skiing, walking, jogging or stair-climbing, while the foot 
supports 24 and 26 move accordingly in response to the motions of the 
feet. 
With reference to FIGS. 1 and 2, the base 22 of the apparatus 20 includes a 
lower section 28 adapted to rest upon a floor 32 or similar (i.e. 
upwardly-facing) support surface and an elevated section 30 joined to the 
lower section 28. As best shown in FIG. 1, the lower section 28 includes a 
main bar 34 which extends in a forward and rearward direction relative to 
the remainder of the base 22 and a pair of parallel cross members 36 and 
38 joined to the main bar 34 in a spaced relationship with one another so 
that the cross members 36 and 38 and bar 34 collectively define a plane, 
and this planar relationship defined by the components of the lower 
section 28 permits the base 22 to rest flatly upon the floor 32 and to 
stably support the apparatus 20 during use. 
The elevated section 30 includes a post 40 which is joined to the lower 
section 28 by way of the main bar 34 thereof so as to extend generally 
upwardly therefrom along a substantially vertical path and a 
horizontally-extending member 42 fixedly joined atop the post 40 at a 
location disposed substantially midway along the length of the member 42. 
As best shown in FIG. 2, each end of the member 42 is directed away from a 
corresponding side of the apparatus 20 and includes a cylindrical end 
portion 43 of reduced diameter and whose purpose will become apparent 
herein. Each bar-like component of the elevated section 30, as well as 
those of the lower section 28, is comprised of a suitable material, such 
as steel, and is fixedly secured to an adjacent component, as with welds. 
With reference to FIGS. 2-4, the apparatus 20 includes left and right 
linkage assemblies 44 or 46, respectively, interposed between the foot 
supports 24 and 26 the base 22. Each of these linkage assemblies 44, 46 is 
joined to a corresponding end portion 43 of the elevated section 30 of the 
base 22 to accommodate a rotational, as well as sliding, movement of the 
foot support 24 to 26 relative to the elevated section 30. To this end and 
as exemplified by the linkage assembly 24 of FIGS. 3 and 4, each linkage 
assembly 44 or 46 includes a first elongated member in the form of an arm 
50 having a linear section 52 and a somewhat arcuate-shaped grip section 
54 joined at its opposite ends to the linear section 52. The arm 50 is 
pivotally and slidably connected to the elevated section 30 by way of a 
connector member 55 (best shown in FIGS. 5 and 6) including a first collar 
portion 56 which is slidably positioned about the linear section 52 (and 
captured between the ends of the grip section 54) and a second collar 
portion 58 which is fixedly joined to the first collar portion 56 in an 
orthogonal relationship therewith. The second collar portion 58 is 
positionable upon a corresponding end section 43 (FIG. 2) of the elevated 
base section 30 and is rotatable with respect thereto so that the 
connector member 55 enables the arm 50 to be pivoted relative to the end 
section 43 (by way of the second collar portion 58) and to be slidably 
moved relative to the end section 43 (by way of the first collar portion 
56). 
With reference again to FIGS. 3 and 4, each linkage assembly 44 or 46 
further includes a second elongated member in the form of a bar 64 which 
is pivotally secured at one end to the arm 50 and a third elongated member 
in the form of a bar 66 which is pivotally secured at its lower end to the 
end of the bar 64 opposite the arm 50 and is rotatably secured at its 
upper end to the end section 43 of the elevated section 30 of the base 22. 
The arm 50 is pivotally joined to the rearward end of the bar 64 by means 
of a pivot pin 65 which extends through aligned openings provided in the 
corresponding ends of the arm 50 and bar 64, and the forward end of the 
bar 64 is pivotally joined to the lower end of the bar 66 by means of a 
pivot pin 67 which extends through aligned openings provided in the 
corresponding ends of the bars 64 and 66. A collar section 69 is fixedly 
joined to the bar 66 adjacent its upper end and is positionable about the 
end section 43 of the elevated section of the base 22 to accommodate the 
rotation (i.e. pivoting) of the bar 66 relative to the base 22 between 
alternative angular positions. Each collar section 68, as well as a 
corresponding connector member 55, is secured upon its corresponding end 
section 43 by way of a nut 57 which is threadably secured upon the end 
section 43. 
It follows from the foregoing that the bar 66 is connected to the arm 50 of 
each linkage assembly 44 or 46 by way of the end section 43 and connector 
member 55. In other words, because the bar 66 is pivotally secured to the 
end section 43 by way of the collar 69 and because the arm 50 is pivotally 
and slidably secured to the end section 43 by way of the connector member 
55, the arm 50 and bar 66 are pivotally and slidably connected to one 
another. 
It also follows from the foregoing that each linkage assembly 44 or 46 
provides a three-member linkage arrangement whose components (i.e. arm 50 
and bars 64 and 66) have ends which are joined to the ends of the other 
components of the assembly 44 or 46 so that relative movement between two 
of these components effects a corresponding movement of the remaining 
component. As can be seen in the comparative views of FIGS. 3 and 4, the 
movement of one of the components 50, 64 or 66 relative to the end section 
43 of the base 22 effects a shift in position between the other components 
50, 64 or 66 relative to the end section 43, and the permitted movement 
between the components 50, 64 and 66 permits the corresponding foot 
support 24 or 26 to be positioned in any of a number of positions in its 
corresponding vertical plane 45 or 47. 
Each foot support 24 or 26 is in the form of a platen-like member capable 
of supporting the weight of the user as the user's feet are positioned 
thereon and is rigidly joined to the bar 64 so as to extend rearwardly 
thereof. Consequently, each foot support 24 or 26 is moved in conjunction 
with movement of the bar 64 to which it is secured. Preferably, each foot 
support 24 or 26 is covered with a rubberized, or other high-friction 
material, to reduce the likelihood of slip between the foot support 24 or 
26 and the foot of a user positioned thereon. 
With reference again to FIG. 1, the apparatus 20 also includes means, 
generally indicated 70, for coordinating the movement of the foot supports 
24 and 26 relative to one another as the foot supports 24, 26 are moved in 
their corresponding vertical plane 45 or 47 (FIG. 2). To this end, the 
coordinating means 70 includes a first coordinating means, generally 
indicated 72, for coordinating the permitted vertical (i.e. upward and 
downward) movement of the foot supports 24 and 26 relative to the base 22 
and a second coordinating means, generally indicated 74, for coordinating 
the permitted fore and aft (i.e. forward and rearward) movement of the 
foot supports 4, 26 relative to the base 22. 
As best shown in FIGS. 7 and 8, the first coordinating means 72 includes a 
tension assembly 76 including a pair of pulleys 68, a pulley assembly 78 
an a cable 80. Each pulley 68 is journaled to the bar 64 adjacent the 
corresponding foot support 24 or 26 for rotation about a horizontal axis, 
and the pulley assembly 78 includes four pulleys 82, 84, 86 and 88 which 
are journaled to a support bar 90 which is, in turn, affixed to the post 
40 of the base 22 adjacent the horizontal member 42. Two pulleys 82 and 84 
are arranged in substantially parallel relationship at the opposite ends 
of the bar 90 for rotation about coincident axes, and each of the other 
two pulleys 86 and 88 is supported from the bar 90 (and generally beneath 
a corresponding pulley 82 or 84) for rotation about substantially 
horizontal and parallel axes. 
The cable 80 has two opposite ends 92 and 94 which are fixedly secured, or 
anchored, to the horizontal member 42 of the base 22 by way of the 
U-brackets 96 and 98 positioned adjacent the corresponding ends of the bar 
42. As the cable 80 is traced from its end 92 toward its end 94, the cable 
80 is routed in sequence through one pulley 68, across the pulleys 82, 86, 
88 and 84 of the pulley assembly 78, and then through the other pulley 68. 
With the cable ends 92 and 94 anchored to the member 42 in this manner, 
the foot supports 24 and 26 are suspended by the cable 80 above the floor 
32. Consequently, the downward movement of a selected one of the foot 
supports 24 or 26 by, for example, a shift of the user's weight toward the 
side of the apparatus 20 corresponding to the selected foot support 24 or 
26 effects the forced upward movement of the other foot support 26 or 24. 
Similarly, the downward movement of the other foot support 26 or 24 by, 
for example, a shift of the user's weight toward the side of the apparatus 
20 corresponding to the other foot support 26 or 24 effects the forced 
upward movement of the opposite, i.e. selected, foot support 24 or 26. For 
illustrative purposes, there is shown in FIG. 7 the relative position of 
the linkage assemblies 44 and 46 when the foot supports 24 and 26 are 
positioned equidistant from the floor, and there is shown in FIG. 8 the 
relative position of the linkage assemblies 44 and 46 when the left foot 
support 24 is positioned at a higher elevation than is the right foot 
support 26. To adjust the elevation of the foot supports 24 and 26 
relative to the floor 32, the bar 90 of the pulley assembly 78 can be 
removed from the post 40 and re-secured thereto by way of any of a number 
of alternative vertically-disposed holes 120 provided along the length of 
the post 40. 
As best shown in FIGS. 9 and 10, the second coordinating means 74 includes 
a tension assembly 100 including a pulley 102 journaled to the main bar 34 
of the lower section 28 of the base 22 and a cable 104 having two opposite 
ends 106 and 108. Each end 106 or 108 of the cable 104 is fixedly secured 
to a corresponding linkage assembly 44 or 46 (by way of a boss 110) 
adjacent the location at which the bars 64 and 66 are pivotally joined to 
one another. In the depicted embodiment 20, each boss 110 is integrally 
joined to the bar 64 of a corresponding linkage assembly 44 or 46. The 
pulley 102 is journaled to the end of the main bar 34 of the base 22 
adjacent the rearward end thereof and is arranged relative to the main bar 
34 so that its rotation axis is oriented vertically. 
Between the ends 106, 108 of the cable 104, the cable 104 is routed through 
the pulley 102 so that rearward movement of the left linkage assembly 44 
effects a forward movement of the right linkage assembly 46, and the 
rearward movement of the right linkage assembly 46 effects a forward 
movement of the left linkage assembly 44. Consequently, the rearward 
movement of a selected one of the foot supports 24 or 26 by, for example, 
a rearward shift of the corresponding foot during an exercise routine 
during which the feet of a user simulate those of a cross-country skier, 
effects the forced forward movement of the other foot support 26 or 24. 
Similarly, the rearward movement of the other foot support 26 or 24 by, 
for example, a rearward shift of the corresponding foot during an exercise 
routine, effects the forced forward movement of the opposite foot support 
24 or 26. For illustrative purposes, there is shown in FIG. 9 the relative 
position of the linkage assemblies 44 and 46 when the foot supports 24 and 
26 are positioned equidistant from (a vertical plane containing) the 
horizontal bar 42, and there is shown in FIG. 10 the relative position of 
the linkage assemblies 44 and 46 when the left foot support 24 is 
positioned forwardly of the right foot support 26. 
It follows from the foregoing that since the foot supports 24 and 26 are 
forced to move in concert with one another when either foot support 24 or 
26 is moved within its vertical plane along either a horizontal or 
vertical direction, the foot supports 24 and 26 also move in concert with 
one another as the foot supports 24 and 26 are moved in non-linear, such 
as circular, paths. For example and has been discussed above, the linkage 
assemblies 44 and 46 enable each foot support 24 or 26 to be moved within 
its vertical plane along a substantially circular path, and this permitted 
movement enables the apparatus 22 to be used as a cycle-type exercise 
device as the user stands upon the foot supports 24 and 26 (as illustrated 
in FIG. 11) and moves his feet along paths resembling those of a cyclist. 
Furthermore, the coordinating means 70 ensures that one foot support 24 or 
26 is in motion when the other foot support 26 of 24 is in motion, and 
vise-versa. 
In addition to the aforedescribed vertical (i.e. upward and downward) 
motion of the foot supports 24 and 26 (whose motion enables the user to 
simulate those involved in a stair-climbing exercise) and the 
aforedescribed back and forth motion of the foot supports 24 and 26 (whose 
motion enables the user to simulate those involved in a ski-type 
exercise), it has been found that the user of the apparatus 20 can move 
the foot supports with his feet to simulate normal walking motion or to 
simulate jogging motion. During any of these exemplary exercises, the user 
holds the grip section 54 of the arm 50 of each linkage assembly 44 or 46 
(as shown in FIG. 11) to help maintain his balance upon the foot supports 
24 and 26 and to facilitate, through his arms, the appropriate motion 
(e.g. pivotal and sliding) of the linkage assemblies 44 and 46 during the 
desired exercise routine. 
For purposes of illustration, there is shown in FIG. 12 a side view of the 
apparatus 20 various exemplary paths along which each foot support can be 
moved during use of the apparatus 20. If, for example, the apparatus 20 is 
used as a cycle-type device, the foot support 24 or 26 can travel along a 
circular path similar to the path 130. By comparison, if the apparatus 20 
is used as a stair-climbing device, the foot support 24 or 26 can travel 
along a somewhat vertically-disposed oval path similar to the path 132, 
and if the apparatus 20 is used as a walking exercise device, the foot 
support 24 or 26 can travel along a somewhat horizontally-disposed oval 
path similar to the path 134. 
The apparatus 20, with its aforedescribed coordinating means 70, is 
advantageous in that it renders movements of the foot supports 24 and 26 
fluid-like and devoid of periods of use during which the user's limbs 
might be exposed to sudden shock forces. For example, as a jogger runs 
along a road, his legs are commonly exposed to sudden shock forces as his 
feet strike the road. If, instead, the jogger were to simulate jogging 
motion upon the apparatus 20, the transfer of weight from one foot to the 
other foot is much more gradual (or fluid-like) and devoid of the shock 
forces that would otherwise be experienced by the sudden impact of his 
feet against the road. 
It follows from the foregoing that an exercise apparatus has been described 
which includes foot supports 24 and 26 which are pivotally and slidably 
movable relative to a base 22 and which are joined to one another in such 
a manner that movement of one foot support 24 or 26 effects movement of 
the other foot support 26 or 24. In addition, the permitted movement of 
each of the foot supports 24 and 26 within a corresponding vertical plane 
permits the user to simulate stair-climbing motions, skiing motions, 
walking and jogging motions, and cycling motions. 
It will be understood that numerous modifications and substitutions can be 
had to the aforedescribed embodiment 20 without departing from the spirit 
of the invention. For example, although the aforedescribed pulley assembly 
78 of the apparatus 20 has been shown and described as including four 
pulleys 82, 84, 86 and 88 wherein each pulley is adapted to rotate about a 
stationary axis, the pulley assembly 78 with its multiple pulleys may be 
exchanged for a single pulley. For example, there is shown in FIG. 13, a 
single pulley 122 which is mounted upon a swivel 124 which, in turn, is 
attached to the base 22 (in place of the pulley assembly 78). Because the 
swivel 124 permits the pulley 122 to move in any of three coordinate 
directions, the pulley 122 effectively self-adjusts in position during the 
movement of the foot supports during use. Accordingly, the aforedescribed 
embodiment 20 is intended for the purpose of illustration and not as 
limitation.