MUSCLE PHYSIOLOGY

Detailed explanation-1: -ATP enables the actin-myosin cross-bridge to detach, and release energy through its hydrolysis to enable the myosin head to return to its normal position.

Detailed explanation-2: -During contraction, the creatine phosphate breaks into creatine and releases phosphorous which combine with ADP to form ATP. The ATP formed is used up by the muscles for contraction.

Detailed explanation-3: -Yes, muscle contraction requires ATP. ATP is in fact a critical requirement for muscle contraction because it breaks the myosin-actin cross-bridge, freeing the myosin for the next contraction. Without ATP, muscles would remain in their contracted state, rather than their relaxed state.

Detailed explanation-4: -Adenosine triphosphate (ATP) is the sole fuel for muscle contraction. During near maximal intense exercise the muscle store of ATP will be depleted in < 1s, therefore, to maintain normal contractile function ATP must be continually resynthesized.