What happens to force production when frequency is increased beyond the plateau frequency?

What happens to force production when frequency is increased beyond the plateau frequency?

• A. Force continues to rise linearly
• B. Force decreases immediately
• C. Force remains near the plateau
• D. Force doubles

Answer: (C)

Beyond the plateau frequency, increasing pulse frequency does not raise force because the muscle has already reached its maximum for the given pulse width and amplitude. The motor units are firing at near-maximal rates and recruitment cannot increase further, so force output stays essentially the same. Pushing frequency higher at this point mainly increases fatigue and discomfort rather than strength. To gain more force, adjust amplitude or pulse width instead of frequency.

Beyond the plateau frequency, increasing pulse frequency does not raise force because the muscle has already reached its maximum for the given pulse width and amplitude. The motor units are firing at near-maximal rates and recruitment cannot increase further, so force output stays essentially the same. Pushing frequency higher at this point mainly increases fatigue and discomfort rather than strength. To gain more force, adjust amplitude or pulse width instead of frequency.