TEST-RETEST RELIABILITY OF WIDE-PULSE HIGH-FREQUENCY NEUROMUSCULAR ELECTRICAL STIMULATION EVOKED FORCE

Introduction: We compare forces evoked by widepulse high-frequency (WPHF) neuromuscular electrical stimulation (NMES) delivered to a nerve trunk versus muscle belly and assess their test-retest intraindividual and interindividual reliability. Methods: Forces evoked during 2 sessions with WPHF NMES delivered over the tibial nerve trunk and 2 sessions over the triceps surae muscle belly were compared. Ten individuals participated in 4 sessions involving ten 20-s WPHF NMES contractions interspaced by 40-s recovery. Mean evoked force and force time integral of each contraction were quantified. Results: For both nerve trunk and muscle belly stimulation, intraindividual test-retest reliability was good (intraclass correlation coefficient> 0.9), and interindividual variability was large (coefficient of variation between 140% and 180%). Nerve trunk and muscle belly stimulation resulted in similar evoked forces. Discussion: WPHF NMES locations might be chosen by individual preference because intraindividual reliability was relatively good for both locations.