What is the typical duration of short EMG bursts during gait?

What is the typical duration of short EMG bursts during gait?

• A. 60-80 ms
• B. 1-2 sec
• C. 100-400 ms
• D. 5-10 sec

Answer: (C)

During gait, muscles activate in brief bursts that align with specific moments of the step, not as a continuous squeeze. Those bursts are short because the limb goes through rapid phases like heel strike, stance, push-off, and swing, with muscle activation tapered between these moments. At normal walking speeds, a full gait cycle is about a second, so the actual active contraction window for a given muscle tends to fall in the range of a few hundred milliseconds. Therefore, 100–400 milliseconds best matches the typical duration of these short EMG bursts during gait. The other options are less representative: 60–80 ms is usually too brief for most muscle activations in walking, while 1–2 seconds or longer would imply sustained activity across much of the cycle, which isn’t characteristic of normal walking patterns.

During gait, muscles activate in brief bursts that align with specific moments of the step, not as a continuous squeeze. Those bursts are short because the limb goes through rapid phases like heel strike, stance, push-off, and swing, with muscle activation tapered between these moments. At normal walking speeds, a full gait cycle is about a second, so the actual active contraction window for a given muscle tends to fall in the range of a few hundred milliseconds.

Therefore, 100–400 milliseconds best matches the typical duration of these short EMG bursts during gait. The other options are less representative: 60–80 ms is usually too brief for most muscle activations in walking, while 1–2 seconds or longer would imply sustained activity across much of the cycle, which isn’t characteristic of normal walking patterns.