The latent period of muscle twitch is 10ms and the contraction period is 40ms. What is the tetanizing frequency (Hz)?

Tetanizing frequency = 1/Contraction period = 1/40ms = 25Hz Tetanizing Frequency As the contractile mechanism does not have a refractory period, on rapid stimulation of a muscle, each new contraction occurs before the preceeding one is over. As a result, the second contraction is added paially to the first, and thus the total strength of contraction rises progressively with increasing frequency . Such a response is called a tetanus (tetanic contraction). It is a complete tetanus when no relaxation occurs between stimuli. Tetany occurs because enough calcium ions are maintained in the muscle sarcoplasm throughout the period of stimulation. Ref: Ganong's Review of Medical Physiology 26th edition Pgno: 107