Interlimb Asymmetry in Elite Soccer Players During Jumping and Change-of-Direction Tasks: Emphasizing Chronic Ankle...

Area of Science:

• Biomechanics
• Sports Medicine
• Rehabilitation Science

Background:

• Chronic ankle instability (CAI) is prevalent in athletes and can lead to deficits in the uninjured limb.
• These contralateral limb deficits can significantly impact interlimb coordination and asymmetry during dynamic movements.
• Accurate assessment of these asymmetries is crucial for tailoring rehabilitation strategies and monitoring athletic performance.

Purpose of the Study:

• To investigate the influence of CAI-induced contralateral limb deficits on interlimb asymmetry during jumping and change-of-direction-speed (CODS) tasks.
• To compare asymmetry patterns between athletes with and without CAI.
• To determine if individual thresholds derived from intralimb variability can reliably identify true asymmetries.

Main Methods:

• A cross-sectional study involving male elite soccer players with (n=32) and without (n=38) CAI.
• Participants performed single-leg hop (SLH), single-leg triple hop, modified-505 (Mod505), and 90°-changes-of-direction tests.
• Statistical analyses included paired and independent sample t-tests and Kappa coefficient to assess interlimb differences and agreement.

Main Results:

• Players with CAI exhibited significantly higher interlimb asymmetries in most tests compared to healthy controls.
• Asymmetries consistently favored the same limb in both groups, with higher agreement in players with CAI.
• Individual thresholds derived from intralimb variability identified similar asymmetry patterns in CODS for injured players (81.25%) and between SLH and Mod505 for healthy players (76.32%).

Conclusions:

• CAI-induced contralateral limb deficits significantly influence the magnitude and direction of interlimb asymmetry, potentially leading to underestimation.
• The findings underscore the importance of considering contralateral limb deficits in athletes with CAI.
• Rehabilitation programs should address these deficits to optimize performance and mitigate injury risk.