Why skeletal muscle can undergo tetanus?

Skeletal muscle can undergo tetanus because of the summation of individual twitches. When a skeletal muscle is stimulated, it undergoes a twitch contraction, which is a brief, single contraction followed by relaxation. However, if the stimulus is repeated before the muscle has a chance to relax, the subsequent twitches will summate, resulting in a sustained contraction known as tetanus. This phenomenon occurs due to the accumulation of calcium ions in the muscle fibers, which prolongs the contraction phase and prevents relaxation. Tetanus allows skeletal muscles to maintain sustained contractions for prolonged periods, which is essential for various activities such as holding objects, maintaining posture, and generating powerful movements.