Effects of bracing and a Futsal-specific fatiguing protocol on muscle reaction time and ground reaction forces

Abstract

Context: Futsal is a rapidly growing sport, with a high prevalence of ankle injuries. It has been found that ankle bracing during sporting activity reduces the incidence of injury, however, research assessing its acute effects on muscle reaction time and ground reaction forces has provided mixed results. Aim: The aim of this thesis was to analyse the effects of bracing on muscle reaction times (MRT) during a simulated lateral ankle sprain, and ground reaction forces (GRF) during a 90-degree cutting manoeuvre, both before and immediately after a futsal-specific fatiguing protocol (FIRP). Participants: Four male participants aged 19-22 who all played for the same University futsal team took part in the study. Methods: Muscle reaction times of the PL, PB and TA were analysed during a simulated lateral ankle sprain, and ground reaction forces during a 90-degree cutting manoeuvre, both before and immediately after the FIRP, when both braced and unbraced. Results: Significant main effects (P < 0.05) were reported during the ANOVAs of lower (improved) MRT of the PL and PB when braced vs. unbraced. A significant main effect was found for increased (worsened) MRT of the tilted PB post-fatigue vs. pre-fatigue (P = 0.032). No significant differences (P > 0.05) were found during post-hoc paired samples t-tests. No significant effects (P > 0.05) regarding GRF were reported between limbs during the 90-degree cutting manoeuvre, when braced and unbraced, pre-, and post-fatigue. Conclusion: Although significant effects were not found, strong trends, supported by large effect sizes (ɳp2 = 0.14>), of improved MRTs when braced, and worsened MRTs post-fatigue were apparent and warrant further research that incorporates a similar study-design and larger sample size.