A tetanic contraction is usually reached at how many pulses per second (pps)?

A tetanic contraction is usually reached at how many pulses per second (pps)?

• A. 10-20 pps
• B. 25-40 pps
• C. 35-50 pps
• D. 60-75 pps

Answer: (C)

Tetanic contraction comes from temporal summation: when the stimulation rate is high enough, the muscle twitches overlap so closely that they fuse into one smooth, continuous contraction rather than separate jerks. If the rate is too low, you see distinct twitches; if it’s too high, fatigue and discomfort can limit performance. Clinically, the most reliable way to get a strong, sustained contraction without undue fatigue is to use a middle-range frequency that produces a fused contraction. That middle range best fits the goal, so it’s the correct choice.

Tetanic contraction comes from temporal summation: when the stimulation rate is high enough, the muscle twitches overlap so closely that they fuse into one smooth, continuous contraction rather than separate jerks. If the rate is too low, you see distinct twitches; if it’s too high, fatigue and discomfort can limit performance. Clinically, the most reliable way to get a strong, sustained contraction without undue fatigue is to use a middle-range frequency that produces a fused contraction. That middle range best fits the goal, so it’s the correct choice.