The claim that electric shocks and membrane depolarization trigger muscle contraction is a well-established physiological fact governed by excitation-contraction coupling, where electrical excitation leads to calcium release and mechanical force generation. Therefore, no formal citation is strictly needed, though extensive literature confirms the mechanism.
The claim states a fundamental physiological principle of excitation-contraction coupling: electrical stimulation or membrane depolarization causes muscle contraction via calcium signaling and membrane potential changes. This is a matter of established scientific textbook knowledge and everyday observation in physiology. Numerous retrieved papers (such as [1], [2], [4], [5]) discuss excitation-contraction coupling in detail, confirming the causal chain from membrane excitation to calcium-mediated contraction. Because it is a universally accepted physiological fact, the verdict is COMMON_KNOWLEDGE, with supportive papers correctly mapped to for_indices.