Back squat velocity to assess neuromuscular status of rugby league players following a match

Abstract

Objectives: Back squat mean concentric velocity (MV) and countermovement jump (CMJ) performance were examined in sub-elite rugby league players post-match to monitor changes in neuromuscular status (NMS) from baseline. Relationships between changes in back squat MV and CMJ performance variables were used to compare back squat MV to an established method to monitor NMS.

Design: Longitudinal observational design.

Methods: 18 male sub-elite rugby league players (mean±SD, 20.5±2.4 yr; 180.0±6.7cm; 93.3±11.2kg) performed 3 repetitions of CMJ and back squat with an individualised, pre-determined load at -2h (baseline), +30min, +24h, and +48h in relation to a match. Back squat MV, CMJ height, CMJ peak power, and CMJ peak velocity were measured with a linear position transducer.

Results: Significant (p<0.05), small to large decreases (ES=0.52-1.24) were observed in back squat MV up to +48h post-match. Significant (p<0.05), small to moderate decreases (ES=0.52-0.70) in CMJ height were also observed up to +24h post-match, returning to baseline at +48h. CMJ peak power and peak velocity post-match changes were not significant compared to baseline (p>0.05). Significant positive correlations were found between changes in back squat MV and CMJ height at +30min (r=0.59; p=0.009) and +48h (r=0.51; p=0.03).

Conclusions: These findings suggest back squat MV may be a suitable alternative or addition to CMJ testing for monitoring NMS in rugby league players.

Keywords: Countermovement jump; Mean concentric velocity; Neuromuscular fatigue; Recovery; Team sport.