Assessing muscle strength asymmetry via a unilateral stance isometric mid-thigh pull
- Publisher: Human Kinetics
<strong>Purpose:</strong> The purpose of this study was to investigate the within-session reliability of bilateral and unilateral stance isometric mid-thigh pull (IMTP) force-time characteristics including peak force (PF), relative PF and impulse at time bands (0-100, 0-200, 0-250 and 0-300 ms); and to compare isometric force-time characteristics between right and left and dominant (D) and non–dominant (ND) limbs.<br/> <strong>Methods:</strong> Professional male Rugby league and multi-sport collegiate male athletes (n=54, age 23.4 ± 4.2 years, height 1.80 ± 0.05 m, mass:88.9 ± 12.9 kg) performed 3 bilateral IMTP trials, and 3 unilateral stance IMTP trials per leg 60 on a force plate sampling at 600 Hz.<br/> <strong>Results:</strong> Intraclass correlation coefficients (ICC) and coefficients of variation (CV) demonstrated high-within session reliability for bilateral and unilateral IMTP PF (ICC =.94, CV = 4.7–5.5%). Lower reliability measures and greater variability were observed for bilateral and unilateral IMTP impulse at time bands (ICC =.81-.88, CV =7.7-11.8%). Paired sample t-tests and Cohen’s d effect sizes revealed no significant differences for all isometric force-time characteristics between right and left limbs in collegiate male athletes (p >.05, d ≤0.32) and professional rugby league players (p >.05, d ≤0.11), however significant differences were found between D and ND limbs in male collegiate athletes (p <.001, d = 0.43–0.91) and professional rugby league players (p < .001, d = 0.27–0.46).<br/> <strong>Conclusion:</strong> This study demonstrated high within-session reliability for unilateral stance IMTP PF;revealing significant differences in isometric force-time characteristics between D and ND limbs in male athletes.