Associations Between Low Frequency Fatigue, Jump Height and Perceptual Measures of Muscle Soreness, Fatigue and Recovery

Pre-programmed muscle electrical stimuli will be applied via Myocene® software using 3 electrodes: 1 cathode (5 x 10 cm) placed transversely over the proximal quadriceps femoris, and 2 anodes (5 x 5 cm) over the distal vastus medialis and vastus lateralis. Sixteen sets of stimuli will be administered with 5 seconds between sets. Each set consists of a single pulse, a train of 5 stimuli at 20 Hz, and a train of 18 stimuli at 120 Hz, with 1-second intervals between. The stimulation intensity starts at 25 mA and increases by 1 mA per set, reaching 40 mA in the final set. The Myocene® software calculates the ratio of low- to high-frequency evoked forces within each set. The outcome (Powerdex) is the median value of these 16 ratios for each leg. This evaluation will be conducted on both legs, taking 2 minutes per leg.