Exercising for abdominal muscles - has spring on central pillar which is compressed between user's hands and knees

摘要

The appliance for exercising the abdominal and thoracic muscles consists of two curved plates which the user places on his knees whilst lying on his back. These plates support a central pillar which forms a guide for a compression spring (12). A collar (11) which slides on the central pillar has two arms with handles. The user presses the handles (2) towards the knees with a force necessary to compress the spring (4). The reaction to this force on the user's knees is supplied by the user's abdominal muscles. The direction of the applied forces can be reversed with an appliance which fits in the hollow at the back of the knee caps.