Surface Electromyography-Based Evaluation of Neuromuscular Recruitment Under Different Resistance Conditions During...

Water-resistance rowing machines are widely used in fitness and rehabilitation; however, the neuromuscular effects of different resistance levels remain unclear. This study investigated resistance-dependent muscle activation during water-resistance rowing using surface electromyography (sEMG). Participants performed rowing exercise under four water-resistance conditions (MIN, Level 2, Level 3, and MAX) while maintaining a fixed stroke rate of 40 cycles/min. sEMG signals from the biceps brachii, triceps brachii, deltoid, latissimus dorsi, rectus femoris, and tibialis anterior were collected using a Delsys wireless system (1000 Hz) and normalized to maximal voluntary isometric contraction (MVIC). Results revealed significant interaction effects between resistance level and muscle group. The biceps brachii exhibited the greatest activation across all resistance conditions, whereas overall muscle activation remained below 40% MVIC. Activation differences were limited among the first three resistance levels but increased substantially at the highest resistance level. These findings support the use of sEMG for quantifying resistance-dependent neuromuscular adaptations and optimizing exercise prescription monitoring.