Muscle Fatigue

A decline in the capacity of a muscle or muscle group to generate force or sustain activity after prolonged or repeated exertion. In human-computer interaction, muscle fatigue is a central concern for input modalities requiring sustained or repetitive motion — notably mid-air gestures in augmented and virtual reality, touchscreen use, and keyboard-driven work. Fatigue manifests as reduced precision, slower response times, discomfort, and eventual task abandonment, and it disproportionately affects users with chronic conditions, motor impairments, or limited endurance. Accessibility-oriented design aims to minimize sustained static loads, provide alternative input modalities, and distribute effort across larger, more fatigue-resistant muscle groups.