The Association between Inter-limb Asymmetry and Athletic Performance Tasks: A Season Long Study in Elite Academy Soccer Players
The aims of the present study were to determine the association between asymmetry and measures of speed and change of direction speed (CODS) performance throughout a competitive soccer season and, determine if any observed changes in asymmetry were associated with changes in speed and CODS performance. Eighteen elite male under-23 academy soccer players performed unilateral countermovement jumps (CMJ), unilateral drop jumps (DJ), 10, 30 m sprints, and 505 CODS tests at pre, mid and end of season. No significant relationships were evident during pre or mid-season between asymmetry and speed or CODS performance. Significant correlations were shown at the end of season between DJ height asymmetry and 10 m sprint time (ρ = 0.62; p = 0.006) and 505 time on the right limb (ρ = 0.65; p = 0.003). No significant correlations between changes in asymmetry and changes in speed or CODS were evident at any time point. Although numerous studies have reported associations between asymmetry and reduced athletic performance, it appears that these associations with speed and CODS do not track consistently over time. Thus, suggestions for the reduction of asymmetry which may indirectly enhance athletic performance cannot be made.