US Patent 7044897 Exercise machine with dual, cooperating weight stacks

An exercise apparatus has an exercise station that is selectively moved by a user and has first and second weight stacks that provide selected resistance to movement of the exercise station. The exercise apparatus includes: (A) a frame; (B) an exercise station; (C) a first weight stack; (D) a second weight stack; and (E) a coupling system configured to selectively couple: (i) the first weight stack; and (ii) the second weight stack to the exercise station such that movement of the exercise station requires movement of at least one plate from each of: (i) the first weight stack; and (ii) the second weight stack. A coupling member couples the first weight stack to the second weight stack.