THE EFFECTS OF INCREASING LOAD ON ELECTROMYOGRAPHIC PARAMETERS IN SELECTED LOWER LIMB MUSCLES DURING THE PARALLEL SQUAT

Abstract

The aim of this study was to establish the effects of increasing load on selected electromyographic parameters during the parallel squat. Electromyograms were recorded from four lower limb muscles for ten male rugby forwards performing three parallel squats at each of three workloads (60%, 70% and 80% of one-repetition maximum). Significant differences () between lowering and raising phases were found in: integrated muscle activity for vastus lateralis, biceps femoris and tibialis anterior; median frequency for vastus lateralis and biceps femoris; zero crossing rate for biceps femoris and tibialis anterior. The change between lowering and raising phases had a greater effect on muscle activation parameters than changes in load. Little evidence was found that working at higher percentages of one-repetition maximum is associated with increasing strength gains.