What is the typical on/off time ratio used for NMES and FES?

• A. 1:1
• B. 5:1
• C. 2:1
• D. 1:5

Answer: (D)

The main idea here is how we manage fatigue with the stimulation pattern, using a duty cycle that balances contraction with recovery. For NMES and FES, you want short bursts of stimulation followed by a longer rest period so the muscle can recover between contractions, maintain force, and reduce fatigue.

The typical on/off time ratio used is 1:5. That means the muscle is stimulated for a brief on period (for example, a few seconds) and then rests for a longer off period (about five times longer). An example would be 5 seconds on, 25 seconds off. This approach helps sustain contraction quality over a session and avoids rapid fatigue.

Other ratios either shorten the rest too much, leading to quicker fatigue, or extend the rest so long that you’re not delivering enough active work during therapy.