Physiology Latent period of muscle twitch is 10 s, contraction period is 40 s and the relaxation time is 50 s. Tetanising frequency would be: A 25 Hz B 50 Hz C 75 Hz D 100 Hz 💡 Explanation Latent period of muscle twitch is 10 s, contraction period is 40 s and the relaxation time is 50 s. Tetanising frequency would be: ✓ Correct Answer: A. 25 Hz