Please sir tell me what is the line say. Force generated by the muscles is used to carry out movement through joints,where the joint acts as a fulcrum.

Dear student, A lever is a rigid bar that moves on a fixed point called the fulcrum, when a force is applied to it. The mentioned line means that in the human body, the joints are fulcrums, and the bones act as levers. Muscle contraction provides the effort that is applied at the muscle’s insertion point on the bone. The load is the bone itself, along with overlying tissues and anything else you are trying to move with that lever. Regards