In a claim about tetanic contractions not being set up by currents, which current is identified as correct?

• A. Low Frequency Current
• B. High Frequency Current
• C. Both
• D. Neither

Answer: (B)

Tetanic contraction happens when muscle fibers are stimulated so rapidly that they cannot relax between impulses, creating a smooth, sustained contraction. Electrical stimulation at high frequencies delivers pulses fast enough for temporal summation, so the muscle fuses individual twitches into tetanus. In contrast, low-frequency stimulation grants time for relaxation between pulses, resulting in separate twitches rather than a fused, tetanic contraction. Therefore, the correct identification is high-frequency current, because only at higher frequencies does the stimulation produce the sustained, tetanic contraction.