Biomechanical Determinants of the Modified and Traditional 505 Change of Direction Speed Test

Dos'Santos, T, McBurnie, A, Thomas, C, Comfort, P, and Jones, PA. Biomechanical determinants of the modified and traditional 505 change of direction speed test. J Strength Cond Res 34(5): 1285–1296, 2020—The aim of this study was to investigate the whole-body biomechanical determinants of 180° change of direction (COD) performance. Sixty-one male athletes (age: 20.7 ± 3.8 years, height: 1.77 ± 0.06 m, mass: 74.7 ± 10.0 kg) from multiple sports (soccer, rugby, and cricket) completed 6 trials of the modified and traditional 505 on their right leg, whereby 3D motion and ground reaction force data were collected during the COD. Pearson's and Spearman's correlations were used to explore the relationships between biomechanical variables and COD completion time. Independent t-tests and Hedges' g effect sizes were conducted between faster (top 20) and slower (bottom 20) performers to explore differences in biomechanical variables. Key kinetic and kinematic differences were demonstrated between faster and slower performers with statistically significant (p ≤ 0.05) and meaningful differences (g = 0.56–2.70) observed. Faster COD performers displayed greater peak and mean horizontal propulsive forces (PF) in shorter ground contact times, more horizontally orientated peak resultant braking and PFs, greater horizontal to vertical mean and peak braking and PF ratios, greater approach velocities, and displayed greater reductions in velocity over key instances of the COD. In addit...
Source: Journal of Strength and Conditioning Research - Category: Sports Medicine Tags: Original Research Source Type: research