Hello. Does anyone know if when the actin and myosin filaments come apart, is the globulin head binding happening in reverse?

Do globulin heads pull the muscles apart after pulling them together or does the myofilament just not bind and slide out?

Is this thermodynamically favorable? What about electric potential? I heard but can't corroborate that the calcium creates an electric potential such that the non-spontaneous reaction ADP + Phosphate -> ATP takes place. When calcium flows out of the muscle do all the reactions happen in reverse, chemically, motorly, thermally and electrically?