Background of the invention

Traditionally, there have been two types of leg presses. The first one is as a pure linear movement. This can be carried out in two ways. Either an exercise device where the person and the seat, which is the most typical solution, move along guide bars, or a solution where the footplate of the device moves but the user is stationary.

In another implementation, the foot plate is attached to a movement arm that rotates around an axis. This allows for a curved trajectory of movement. In one example of such a device, a footplate is attached to a movement arm which is connected to the device via an axle. When used, the foot plate moves on a trajectory which first turns upwards, i.e. in the wrong direction in terms of movement for the user, and then starts to descend and returns height wise either to the same height or a slightly lower height than that of the initial position. If the foot plate would immediately begin to turn downwards, as would be correct in terms of a correct physiological movement, the movement would end up being more downward than forward, which would make the movement impossible.

When studying the biomechanics of the hip and knee, it can be seen that at the beginning of the movement the movement is arc-like, but towards the end it becomes more linear. Here, the movement pattern produced by stair climbing has been studied in particular. With the current solutions, the movement models are incorrect and limit the effect of the exercise either more to the hip extension muscles or knee extension muscles.

The present invention solves or at least alleviates the problems with the solutions mentioned above. With the present invention a natural elliptic trajectory, very close to stair climbing, is achieved. Summary of the Invention

The present problems are solved by a leg press device comprising a frame, a seat attached to the frame, a footplate attached to a movement arm, which movement arm is movable around an axis, wherein the movement arm is attached to a sledge that moves linearly forward and backward on the frame. Further a movement means is attached between the frame and movement arm enabling for a movement of the sledge, which in the beginning of the movement of the movement arm is small but gradually increases toward the end of the movement trajectory.

Brief description of the figures

Figure 1 shows one embodiment of the leg press device seen from a side view in a starting position where the foot plate is in a in an initial position before starting the exercise,

Figure 2 shows one embodiment of the leg press device seen from a side where the foot plate has been pressed forward by a user.

Detailed description of the Invention

The invention is below described in detail with references made to the figures.

The present problems are solved by a new kind of leg press. One embodiment of the leg press device 1 can be seen in figure 1. The device comprises a frame 2. A foot plate 4 is attached to a movement arm 3, which movement arm 3 rotates around an axis 6. A seat 5 is attached to frame 2 of the device. The movement arm 3 with its axis is from the lower part attached to a sledge 8 that moves linearly forward and backward on the frame 2 according to a direction showed by an arrow 9 in the figure. The movement is produced by a lever arm 7, which is fixedly attached to the frame 2 and rotatably attached to the movement arm 3. This causes a small movement at the beginning of the trajectory of movement, but the movement accelerates the further the movement arm 3 rotates. With this, the desired trajectory is achieved, where the radius of the orbit of the foot plate increases towards the end of the movement.

According to an alternative embodiment of the invention, the movement means 5 is a cable which is pulled forward by an eccentric cam in the movement arm. Also, other solutions for the movement means may be possible.

Figure 2 shows one embodiment of the leg press device 1 seen from a side view, where the foot plate has been pressed forward by a user. In the figure an example of a trajectory of movement of the foot plate 4 can be seen. According to the invention the movement trajectory of the foot plate of the leg press is such that the effective radius of the footplate orbit around its axis increases towards the end of the movement. The trajectory of movement is illustrated by the curved lines D in figure 2.

According to an embodiment of the invention the radius of the foot plate orbit around its axis increases by e ratio of 3/1 from the beginning toward the end of the movement.

This trajectory of movement ensures a balanced load throughout the entire movement. Contrary to the state of the art leg press devices, the load does not wary from the beginning toward the end of the movement as may be the case today. This ensures that there is a load present also at the very end of the movement.

This effect is achieved by the use of the sledge 8 which is moving on the frame away from the user when the user presses the footplate by extending his legs and hips. The movement of the footplate away from the user results in an accelerating arc, i.e. the effective radius of the footplate around its axis, measured from the initial position of the axis before beginning of the movement grows as the movement advances. In other words, the footplate travels along an arc which is not circular but more elliptic. In this manner mimicking a more natural movement. This movement resembles the movement when climbing stairs, a person rising or getting up. This again enables for exercise in a manner that will rehabilitate the user to cope in normal life such as walking, rising, climbing stairs and the like. At the starting position of the movement, the position of the movement arm is adjusted by lengthening and shortening a cable running from the movement arm to the weight pack. This is done by adding one extra pulley to the cable's path, by moving of which, the "length" of the cable becomes longer or shorter, causing the position of the lever to change. This makes it easier to enter the device when the foot plate is moved away from the seat and after that, the foot plate can be moved towards the user in the seat as far as desired.

The position of the seat may also be adjusted. Allowing for adjustment of the seat is important because it allows people of different sizes to be optimally positioned in relation to the movement arm. The adjustment is done by moving the seat forward with straight legs until the movement arm is in the extreme position and from there backing the seat up a little.

Preferably the initial position of the exercise may be chosen by the user, thus enabling training both with an extended knee at an angle of for example 120 degrees between the upper and lower leg or with a bent knee where the angle would be for example around 90 degrees. According to this embodiment the initial position for the beginning of the movement may be defined by the user before beginning the exercise. This may be done automatically by a motor controlling a cable adjustment of the device.

According to the invention the position of the foot plate of the device is not fixed to the movement arm. The foot plate is attached to the movement arm with a joint, and in addition, the foot plate is adjusted by another auxiliary movement arm to an optimal angle and keeps this angle throughout the exercise even if the angle of the movement arm turns strongly.

Also, the backrest of device may be adjustable in order for the device to suit each user optimally. The optimal seat position is where the movement arm and the sledge almost reach the end position. This way the benefit of the elliptic movement pattern benefits users of all sizes. Adjusting the seat, adjusting the entry position of the foot plate and selection of the load of the device may be carried out automatically before training. In this case the user will have a means of identification, which will be read at the exercising device. For example, an RFID-card may be used for this purpose. Upon reading of the card with an RFID reader in the device, the correct weight is selected, as well as the correct seat and movement arm ad- justments are made, and the user interface indicates when the device is ready for use. For example, a red blinking light may indicate that the device is not ready, and a text Ready or a green light may indicate that the device is ready for use.

The device may be used also as strength testing device. A locking mechanism locks the movement arm in a selected position and with a load sell at the end of the lever arm connecting the movement arm and the frame, which causes the sledge's forward movement, will measure horizontal forces applied against the immovable footplate.