Single measurement reliability and reproducibility of volitional and magnetically-evoked indices of neuromuscular performance in adults

This study documents intra-session and inter-day reproducibility (coefficient of variation [V%]) and single measurement reliability (intra-class correlations [RI]; standard error of a single measurement [SEM%] [95% confidence limits]) of indices of neuromuscular performance elicited during peripheral nerve magnetic stimulation. Twelve adults (five men and seven women) completed 3 assessment sessions on 3 days, during which multiple assessments of knee flexor volitional and magnetically-evoked indices of electromechanical delay (EMDV; EMDE), rate of force development (RFDV; RFDE), peak force (PFV; PTFE), and compound muscle action potential latency (LATE) and amplitude (AMPE) were obtained. Results showed that magnetically-evoked indices of neuromuscular performance offered statistically equivalent levels of measurement reproducibility (V%: 4.3–31.2%) and reliability (RI: 0.98–0.51) compared to volitional indices (V%: 3.7–25.2%; RI: 0.98–0.64), which support the efficacy of both approaches to assessment and the indices PFV, EMDV, EMDE and LATE offer the greatest practical utility for assessing neuromuscular performance.