seen as a cross-bridge between actin and myosin filaments in muscle, acts as the motor domain of the molecule and pulls actin filaments along by repetitive conformational changes coupled to ATP ...

It has something to do with a sliding interaction between actin and myosin. In 1954, scientists published two groundbreaking papers describing the molecular basis of muscle contraction.

In this type of contraction, a protein in your muscles called myosin binds to another protein called actin and drags it to shorten muscle fibres. Now imagine you start at the top: your muscles are ...