Lie facedown on a leg curl machine, and hook your ankles under the padded bar.

Intimately involved in the fight or flight response, the psoas can curl you into a protective fetal ball or flex you to prepare the powerful back and leg muscles to spring into action.

Base on elucidating the meaning of "curl leg-drive technique" and the hip-drive , the article analysis the linkage between the two chiefly from the physical view .