Contraction protocol 2: fatigued muscle
fatigue
CONTRACTION, CONTRACTIONS
After the unfatigued protocol was completed, a second protocol was performed that involved a fatigue-inducing sustained maximal contraction. Each participant held a maximal contraction until their force had reduced to 60% of their initial unfatigued MVC. This ensured that each trial, and each participant, had the same level of fatigue (decline in force) for neurophysiological assessments. Immediately after 60% MVC was reached, the participant performed a brief (4 s) submaximal contraction (10%, 25%, 50%, or 75% MVC). The submaximal contractions were based directly off the (fatigued) 60% MVC. Participants performed 5 contractions for each target torque. Each maximal contraction within protocol 2 was a sustained maximal contraction, in which the cortical and brachial plexus stimulation were delivered once the participants force had dropped to 60% of initial MVC. The sustained maximal contractions were followed directly by a brief (4 s) submaximal contraction (Fig. 