The main function of triads is to facilitate the rapid and efficient transmission of the action potential from the surface of the muscle cell to its interior. When an action potential travels along the sarcolemma and down the T-tubules, it triggers the release of calcium ions from the sarcoplasmic reticulum into the cytoplasm. This release of calcium ions is crucial for muscle contraction, as it initiates the interaction between actin and myosin filaments.
