Patent Application
20110152041
The present invention relates generally to foot stretchers and, in particular, to foot stretchers used in conjunction with rowing vessels or mechanical rowing apparatus. The invention is especially useful in rowing vessels that are designed and equipped for professional or competitive racing. It should be understood however that the invention is intended for broader application and use.
The term “foot stretcher” is commonly used to refer to the apparatus found in rowing boats which allows for the rowers' feet to be fixed to the chassis of the boat. Historically, the foot stretcher has consisted of a foot plate which is attached to the chassis of the boat by means of adjustable tracks, and a shoe plate which is bolted to the foot plate and to which a pair of shoes are permanently attached. This does not provide the rower with any form of heel support and therefore forces exerted by the rower against the foot plate are not efficiently balanced. Furthermore, this design only allows the rower limited freedom of movement in relation to their foot positioning on the foot plate.
The rower responsible for steering the boat generally has a slightly modified foot stretcher arrangement which typically includes a separate right foot stretcher being attached to a pair of cables that run (in a criss-cross manner) from the bow of the boat, to the rudder located at the stern. If the rower rotates his right foot toward the starboard side of the boat, the cable attached to the port side of the rudder tightens and shifts the rudder toward the port side of the boat. This has the effect of steering the bow of the boat in a leftward direction. The converse applies if the rower rotates his right foot toward the port side of the boat.
In current implementations of foot stretchers, the rower's feet are inserted into a pair of shoes or restraints, which are permanently attached to the shoe plate in a fixed position. The major drawback of this design is that when the rower's feet are held in this relatively fixed position, the rower's legs are constrained to producing a force along a set vector as opposed to the rower's preferred muscle vectors. This results in a reduced power output by the rower and an additional exertion of the rower's muscles in order to stabilize the legs and pelvic region. This represents a considerable waste of the rower's energy and a restriction of the rower's full leg power potential. Recent literature supports the biomechanical theory that the greatest leg power output results when there is some freedom of movement in relation to the rower's feet, ankles, knees and hips.
The rigidity of these existing foot stretcher designs predisposes rowers to lower limb and lower back injuries. This is a common ailment of competitive rowers and one that often affects their performance and lifetime in the sport. Forcing muscles to push against resistance in vectors that are not compatible with the natural posture of the lower leg can cause stress and strain on the joints and stabilizing muscles of the lower limbs and pelvic region, which predisposes the rower to subsequent injury.
A further limitation of current foot stretcher designs relates to the manner in which the shoe is attached to the foot plate. Existing designs generally require at least the forefoot portion of the rower's shoes to be permanently attached to the foot plate. Predominantly, these designs do not allow for movement or rotation of the shoes once they are attached to the foot plate.
Therefore, it is a desire of the present invention to address these shortcomings to allow for movement and efficient positioning of the rower's feet and lower limbs. It is a further desire of the present invention to increase the maximum speed of rowing boats by enabling rowers to increase their leg power output. In doing so, it is believed that the incidence of lower limb and lower back injuries in rowers can be significantly reduced.
Discussion or mention of any piece of prior art in this specification is not to be taken as an admission that the prior art is part of the common general knowledge of the skilled addressee of the specification in Australia or any other country.
According to one aspect of the present invention there is provided a foot stretcher for use with a rowing vessel or a mechanical rowing apparatus, the foot stretcher including:
a shoe support having attachment means for attaching the shoe support to a rowing boat or rowing apparatus and a mounting for the shoe of a rower;
the shoe support including a sole plate having a forefoot portion and a heel portion, and a movable heel plate,
wherein the angular position of the heel plate relative to the forefoot portion of the sole plate is adjustable to suit individual rowers and their requirements.
Preferably, the heel plate is pivotally attached to the sole plate. It is also preferable that the heel plate is hingedly attached along a transverse plane proximate a mid-foot portion of the sole plate.
The angular position of the heel plate relative to the forefoot portion of the sole plate is preferably adjustable substantially in the range from 5 degrees to 40 degrees. Further, it is preferable that the angular position of the heel plate relative to the forefoot portion of the sole plate is preferably adjustable substantially in the range from 15 degrees to 35 degrees. In a particularly preferred embodiment, the angle between the heel plate and the forefoot portion of the sole plate is at least 20 degrees.
The angular position of the heel plate relative to the forefoot portion of the sole plate may be incrementally adjustable. Alternatively, the angular position of the heel plate relative to the forefoot portion of the sole plate may be continuously adjustable.
Furthermore, the angular position of the heel plate relative to the forefoot portion of the sole plate may be fixed relative to the forefoot position of the sole plate by means of a locking arrangement. Preferably, this locking arrangement includes a first member attached to the heel plate including a plurality of first openings for receiving a pin, and at least one second opening for receiving a pin provided in the sole plate or in a second member attached to the sole plate, wherein the angular position of the heel plate relative to the forefoot portion of the sole plate can be fixed by insertion of a locking pin through any one of the plurality of first openings and the at least one second opening.
Alternatively, the angular position of the heel plate relative to the forefoot portion of the sole plate may be adjustable by means of a screw arrangement located between the heel plate and the heel portion of the sole plate. Preferably, this screw arrangement includes a worm screw which engages both the heel plate and heel portion of the sole plate, and an adjustment means connected to the worm screw, and located substantially within the sole plate, wherein rotation of the adjustment means has the effect of either increasing or decreasing the angular position of the heel plate relative to the forefoot portion of the sole plate.
In a further alternative, the angular position of the heel plate relative to the forefoot portion of the sole plate may be adjustable by insertion of a detachable heel member of appropriate dimensions between the heel plate and the heel portion of the sole plate. The detachable heel member preferably includes an upper surface and a lower surface which converge towards one another at a first end. Preferably, the angle between the upper surface of the heel member and the lower surface of the heel member falls substantially in the range from about 1 degree to about 45 degrees. Further, the heel member is preferably positioned such that an upper surface of the heel member contacts a lower surface of the heel plate and a lower surface of the heel member contacts an upper surface of the heel portion of the sole plate. The heel member is preferably held in position between the heel plate and the heel portion of the sole plate by magnetic forces.
According to a further aspect of the present invention there is provided a foot stretcher kit including a foot stretcher according to the preceding aspect of the invention and further including a set of interchangeable heel members of differing dimensions and/or characteristics.
Preferably, the angle between the upper surface of a heel member and the lower surface of a heel member is different for different heel members of the set. Further, the angles between the upper and lower surfaces of different heel members of the set preferably range from between approximately 1 and 45 degrees.
According to a still further aspect of the present invention there is provided a foot stretcher for use with a rowing vessel or a mechanical rowing apparatus, the foot stretcher including:
a shoe support having attachment means for attaching the support to a rowing boat or rowing apparatus and having a mounting for the shoe of a rower;
wherein the shoe support is rotatable relative to the attachment means to suit individual rowers.
The shoe support is preferably rotatable about an axis of rotation that extends perpendicularly to the longitudinal and lateral directions of the shoe support.
Preferably, the shoe support has a forefoot portion and a heel portion, the shoe mounting being provided on the forefoot portion of the shoe support.
The axis of rotation for the shoe support is preferably provided rearwardly of the shoe mounting below the heel portion of the shoe support. It is also preferable that the attachment means includes a pivot pin or screw forming the axis of rotation for the shoe support. The axis of rotation for the shoe support is preferably located approximately two thirds along the length of the shoe support from the front of the shoe support.
It is possible that the axis of rotation provided by a foot stretcher design could be located beneath the rower's forefoot as this is the point where the shoe is screwed into, and attached to, the foot plate. The positioning of the axis of rotation beneath the forefoot, however, is not congruent with the anatomical requirements of the rower. A rower requires rotation at the shoe to allow for both: motion associated with dorsi flexion and plantar flexion around the ankle complex during a rowing stroke; and motion associated with pelvic-femoral movements during a rowing stroke. The motion of the ankle complex requires that the axis of rotation be offset just anterior to the shaft of the tibia whereas the motion of the pelvic-femoral movements requires the axis of rotation to be aligned with the longitudinal axis of the shaft of the tibia. Neither of these motions are efficiently facilitated by positioning the axis of the rotation beneath the forefoot of the rower.
The shoe support is preferably rotatable in a series of discrete positions. It is also preferable that the shoe support is rotatable between angles of up to about 25 degrees relative to the longitudinal axis of the rowing vessel or apparatus. In a particularly preferred embodiment, it is preferable that the shoe support for a non-steering foot is rotatable between angles of up to about 16 degrees relative to the longitudinal axis of the rowing vessel or apparatus. In coxless boats in which the boat is steered by a rower using one of their feet to move the rudder, the degree of rotation for the steering foot may exceed 16 degrees.
Preferably, the shoe support includes a sole plate having a forefoot portion and a heel portion which extends at an angle relative to the forefoot portion.
According to a still further aspect of the present invention there is provided a foot stretcher for use with a rowing vessel or a mechanical rowing apparatus, the foot stretcher including:
a shoe support having attachment means for attaching the shoe support to a rowing boat or rowing apparatus and a mounting for the shoe of a rower;
the shoe support including a sole plate having a forefoot portion and a heel portion;
wherein the heel portion extends at an angle relative to the forefoot portion of the sole plate.
The angle between the heel portion and the forefoot portion of the sole plate preferably falls substantially in the range from 5 degrees to 40 degrees. Further, it is preferable that the angle between the heel portion and the forefoot portion of the sole plate falls substantially in the range from 15 degrees to 25 degrees. In a particularly preferred embodiment, the angle between the heel portion and the forefoot portion of the sole plate is preferably about 20 degrees.
According to a still further aspect of the present invention there is provided a foot stretcher for use with a rowing vessel or a mechanical rowing apparatus, the foot stretcher including:
two shoe supports, each having attachment means for attaching the shoe support to a rowing boat or rowing apparatus and a mounting for the shoe of a rower,
wherein each of the shoe supports is adjustable independently of one another to suit individual rowers and their requirements.
Preferably, each of the shoe supports is rotatable relative to their respective attachment means and rotatable independently of one another. Each of the shoe supports may also include a corresponding sole plate having a forefoot portion and a heel portion, and a movable heel. It is preferable that the angular position of the heel plate relative to the forefoot portion of the sole plate for each of the shoe supports is independently adjustable to suit individual rowers and their requirements.
The axis of rotation for each of the shoe supports is preferably provided rearwardly of the shoe mounting below the heel portion of the sole plate. It is also preferable that the attachment means includes a pivot pin or screw forming the axis of rotation for the shoe support. The axis of rotation for the shoe support is preferably located approximately two thirds along the length of the shoe support from the front of the shoe support.
Preferably, each of the two shoe supports also includes a corresponding sole plate having a forefoot portion and a heel portion, and a movable heel plate. The angular position of the heel plate relative to the forefoot portion of the sole plate for each of the shoe supports may also be independently adjustable to suit individual rowers and their requirements.
Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. These embodiments are given by way of illustration only and other embodiments of the invention are possible. Consequently, the particularity of the accompanying drawings is not to be understood as superseding the generality of the preceding description.
In the drawings:
Embodiments of the foot stretcher will now be described with reference to the accompanying drawings. Whilst suitable for use in rowing vessels, the foot stretcher may also be installed for use with rowing apparatus, such as those commonly found in gymnasiums.
As shown in
The shoe mounting 124 allows the front portion of the sole of the rower's shoe to be fixed to the sole plate 102, approximately where the ball of the rower's feet would be positioned. The pivot 120 is fixably attached to the lower surface 110 of the sole plate 102 and positioned at a point approximately two thirds along the length of the sole plate 102 from the front of the sole plate. The sole plate 102 is preferably freely rotatable to allow movement of the forefoot portion 142 in a lateral direction and movement of the heel portion 144 in the opposite lateral direction, within predefined discrete positions or bounds which can be increased or decreased to suit the individual requirements of the rower. Preferably, the sole plate 102 is rotatable about the pivot 120 at angles of up to about 25° relative to the longitudinal axis of the rowing vessel. However, it is also preferable that the shoe plate 102 for a non-steering foot is rotatable at angles of up to about 16° relative to the longitudinal axis of the rowing vessel.
It is possible that the axis of rotation or pivot 120 provided by a foot stretcher design could be located beneath the forefoot portion 142 of the sole plate 102 as this is the point where the shoe is screwed into, and attached to, the foot plate. The positioning of the axis of rotation or pivot 120 beneath the forefoot, however, is not congruent with the anatomical requirements of the rower. A rower requires rotation at the shoe to allow for both: motion associated with dorsi flexion and plantar flexion around the ankle complex during a rowing stroke; and motion associated with pelvic-femoral movements during a rowing stroke. The motion of the ankle complex requires that the axis of rotation be offset just anterior to the shaft of the tibia whereas the motion of the pelvic-femoral movements requires the axis of rotation to be aligned with the longitudinal axis of the shaft of the tibia. Neither of these motions are efficiently facilitated by positioning the axis of the rotation beneath the forefoot of the rower.
The angle between the forefoot portion 142 and the heel portion 144 of sole plate 102 falls substantially in the range from 5° to 40°. Preferably, the angle between the forefoot portion 142 and the heel portion 144 of sole plate 102 falls substantially in the range from 15° to 25°. In a particular preferred embodiment, the angle between the forefoot portion 142 and the heel portion 144 of sole plate 102 is about 20°. The angle provided between the forefoot portion 142 and the heel portion 144 of sole plate 102 allows the rower to transmit greater forces through the heel of the foot and therefore perform a more efficient rowing stroke.
The foot stretcher further includes a heel plate 106 which is hingedly attached to the upper surface 108 of the sole plate 102. The dimensions of the heel plate 106 are smaller than that of the sole plate 102 however; the heel plate 106 substantially overlaps the heel portion 144 of the sole plate 102. The heel plate 106 is attached to the upper surface 108 of the sole plate 102 by means of a hinge 126 which substantially spans the width of the sole plate 102 and is positioned proximate the mid-foot portion of the sole plate 102. The hinge 126 allows for rotation of the heel plate 106 relative to the sole plate 102. During use, a lower engagement surface of the shoe contacts the upper surface 112 of the heel plate 106.
Adjusting the angular limits of rotation of the sole plate 102 has the effect of increasing or restricting the degree of movement of the rower's foot during a rowing stroke. The angular limits of rotation are congruent with the anatomical motion of the ankle complex and the hip joint, and allow for an optimal axis for the horizontal loading of the lower limb. The position of the pivot 120 allows for the natural motion of the lower limb of the rower when required, without creating new stresses to the limb or associated instabilities. This position of the pivot 120 allows for motion of both the ankle complex and the pelvic-femoral movements without disadvantaging either of these biomechanical motions.
According to one embodiment of the present invention, the foot stretcher includes a locking arrangement 200 to allow the angular position of the heel plate 106 to be fixed relative to the forefoot portion 142 of the sole plate 102, as shown in
The locking arrangement 200 allows the angular position of the heel plate 106 to be adjustable substantially in the range from 5° to 40°, and preferably adjustable substantially in the range from 15° to 35°. In most instances, the angular position of the heel plate 106 relative to the forefoot portion 142 of the sole plate 102 will be fixed to at least 20°. The various alignment combinations provided by the plurality of first openings 204 and the at least one second opening 206, allow for the angular position of the heel plate 106 to be incrementally adjusted in increments of about 2°. The angular position of the heel plate 106 can therefore be fixed in an elevated position, as shown in
According to a further embodiment of the present invention, the foot stretcher includes a screw arrangement 300 to allow the angular position of the heel plate 106 relative to the forefoot portion 142 of the sole plate 102 to be adjustable, as shown in
The screw arrangement 300 allows the angular position of the heel plate 106 relative to the forefoot portion 142 of the sole plate 102 to be continuously adjustable. As with the embodiment described above with reference to
According to a still further embodiment of the present invention, the foot stretcher 400 shown in
The angular position of the heel plate 106 relative to the forefoot portion 142 of the sole plate 102 is adjusted by insertion of a heel member 402 having a larger or smaller angle between the upper surface 404 and lower surface 406. In this respect, the angle between the upper surface 404 and the lower surface 406 preferably ranges between approximately 1° and 45°. A set of heel members 402 is preferably provided with the angle between the upper surface 404 and the lower surface 406 of each heel member 402 preferably increasing in 1° increments. In order to reduce the number of heel members 402, the increments can also be increased to 2° or higher.
By having a selection of detachable heel members 402, the rower is advantageously able to remove and attach the most appropriate heel member 402 to raise or lower the angular position of the heel plate 106 relative to the forefoot portion 142 of the sole plate 102. This enables a greater surface area of the rower's shoe to remain in contact with the foot stretcher 400 for a longer duration during rowing strokes. This in turn allows for greater forces to be transmitted by the rower during a rowing stroke.
According to a still further embodiment of the present invention, the foot stretcher 500 shown in
Each of the shoe supports also includes a heel plate 106 which is hingedly attached to the upper surface 108 of the sole plate 102. Each of the sole plates 102, consists of a forefoot portion 142 and a heel portion 144. As in the embodiments described above with reference to
As the present invention may be embodied in several forms without departing from the essential characteristics of the invention, it should be understood that the above described embodiment should not be considered to limit the present invention but rather should be construed broadly. Various modifications and equivalent arrangements are intended to be included within the spirit and scope of the invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2008904215 | Aug 2008 | AU | national |
| 2009902475 | Jun 2009 | AU | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/AU09/01058 | 8/17/2009 | WO | 00 | 2/15/2011 |
