A COMPARISON OF THE ISOMETRIC FORCE FATIGUE-RECOVERY PROFILE IN TWO POSTERIOR CHAIN LOWER LIMB TESTS FOLLOWING SIMULATED FOOTBALL. Issue 4 (1st February 2017) - Alcaraz, Pedro E.
Abstract : Background: Lower limb posterior chain isometric peak force (IPF) measured in the supine position was found to be sensitive to match induced fatigue in footballers (McCall et al . 2015). However, hamstrings fatigue following simulated football may be greatest close to full knee extension (Cohen et al . 2014), and the majority of hamstring strains occur in an extended position (Mendiguchia et al . 2012). Objective: To evaluate the effects of a simulated match on IPF in a novel test and a supine position test immediately post, and at +48 h, and +72 h post-match. Design: A within-subject, repeated-measures design was used to investigate the short-term effects of fatigue following a simulated football match-protocol –the BEASTmod90 4 (Akubat et al . 2014). Participants: 17 semi-professional players (age 21.2±2.4 yrs, body mass 73.8±8.9 kg) competing in a Spanish Third-Division team volunteered to participate in the study, which was implemented after the end of their competitive season. Interventions: IPF was measured using a portable force platform immediately before (PRE) and after (POST) the BEASTmod90 protocol, and at +48 h and +72 h post match. Two tests were used: (i) Standing with tested leg at 90° hip and 20° knee flexion (90:20); (ii) Supine with tested leg at 90° knee and hip flexion (S90). Main Outcome Measurements: Fatigue after a simulated football match-protocol. We hypothesized that the 90:20 would show greater levels of fatigue than the S90. Results: IPF significantly declined PRE versus POST match in the 90:20 in both legs (p<0.001), and in the S90 in the non-dominant (p<0.001) and dominant leg (p<0.01). IPF was significantly lower at +48 h compared to PRE in the 90:20 in both legs (p<0.01, p≤0.05), but not in the S90. At +72 h, IPF was not significantly different from PRE in either test. Conclusions: These findings suggest potential angle-specific differences in posterior chain fatigue following a simulated match, and that the 90:20 may be more sensitive to post competition residual posterior chain fatigue.