fting a large amount of weight and yet the weight must be supported by the lifter's arms and shoulders. In addition, it is one of the most dangerous exercises since it typically is terminated by placing the barbell on a rack when the lifter's legs are fully extended. Yet as the lifter approaches his or her limit it becomes difficult to obtain this position. Furthermore, the weight tends to throw lifters forward and cause them to lose their balance. Thus, it is usually necessary to have two spotters when performing the squat. As a result, this exercise is frequently not used by anyone but very experienced weight lifters. Even then the weight used is often less than what the legs are capable of lifting and thus less than maximum affect is achieved.
While exercise apparatus have been developed to perform the squat, the prior art devices of this type are complex and expensive. They also utilize cables and cams or a similar mechanism to lift the weights used for resistance. Thus, the weights are raised and lowered on every repetition which must be done at a rather slow speed and they provide little aerobic affect. A typical prior art squat apparatus is disclosed in Jones, U.S. Pat. No. 4,511,137.
The subject invention overcomes the shortcomings of the prior art by providing an exercise apparatus in which a platform, having a seat that will support the back and head of a user of the apparatus, is rotatably mounted to a frame which sets on the floor. This is accomplished through a pivot arm that is fixedly attached to the platform and rotatably attached to the frame. The platform and pivot arm are arranged so that the platform moves between a first position where the legs of a user who is laying on the seat are bent approximately 90 degrees at both the knees and hips when the user's feet are placed on a leg support that extends upwardly from the base, and a second position where the user's legs are substantially fully extended. A resistance device resists movement of the platform between its first and second positions.
