The active site on actin is exposed as Ca2+ binds troponin
The myosin head forms a cross-bridge with actin
During the power stroke, the myosin head bends, and ADP and phosphate are released
A new molecule of ATP attaches to the myosin head, causing the cross-bridge to detach
ATP hydrolyzes to ADP

and phosphate, which returns the myosin to the "cocked" position.