MEDICAL PHYSIOLOGY

Detailed explanation-1: -Excitation–Contraction–Relaxation Cycle. The muscle action potential triggers a sequence of actions that ultimately results in the contraction and relaxation of the muscle fiber. This sequence is called the excitation–contraction–relaxation cycle.

Detailed explanation-2: -The latent period, or lag phase, the contraction phase, and the relaxation phase. The latent period is a short delay (1-2 msec) from the time when the action potential reaches the muscle until tension can be observed in the muscle.

Detailed explanation-3: -Sliding Filament Theory of Muscle Contraction Once the muscle fiber is stimulated by the motor neuron, actin, and myosin protein filaments within the skeletal muscle fiber slide past each other to produce a contraction. The sliding filament theory is the most widely accepted explanation for how this occurs.