Changes in muscle activation and conduction velocity during sustained contractions following endurance and high-intensity interval training

Abstract

Purpose: Although endurance (END) and high-intensity interval training (HIIT) induce similar metabolic and cardiopulmonary adaptations, recent research suggests that these training approaches may induce opposite adjustments in neuromuscular function. In particular, HIIT increases maximal strength while END training increases the time to task failure during sustained submaximal contractions. The aim of the current study was to examine if changes in endurance, measured as time to task failure, following training is reflected in changes in muscle fibre conduction velocity (MFCV) and/or high-density surface electromyography (HDEMG) amplitude.