Functional Ipsilateral and Bilateral Strength Ratios in Young Elite Athletes Across Multiple Sports Disciplines

Abstract

This research investigates functional strength ratios in young elite athletes across different sports disciplines with different movement characteristics, focusing on the relationship between these ratios and physical performance. Purpose: the study aims to examine the differences in functional ipsilateral and bilateral strength ratios among athletes in symmetrical, asymmetrical, and hybrid sports and assess how these disparities impact strength parameters. Material & Methods: the study comprised 56 male athletes aged 18-28, excluding those with lower limb injuries or limitations affecting performance. The participants were divided into symmetrical, asymmetrical, and hybrid sports categories. Strength assessment utilised an isokinetic dynamometer, focusing on quadriceps-to-hamstring strength and bilateral strength ratios. The study employed MANOVA as the major statistical test for the purpose of the study. Results: athletes in asymmetrical sports demonstrated higher bilateral symmetry in knee extensors compared to symmetrical (0.94±5.98) and hybrid sports (4.9±10.32), with values of 12.89±8.56. The functional hamstring to quadriceps (H:Q) strength ratio showed lower ratios in hybrid sports (right limb: 0.60±0.12, left limb: 0.61±0.09) compared to symmetrical (right limb: 0.79±0.16, left limb: 0.94±0.27) and asymmetrical sports (right limb: 1.05±0.26, left limb: 1.03±0.24), yet within normative values. These findings suggest that sport-specific demands significantly influence functional strength ratios, highlighting the importance of tailored training and rehabilitation programs. The observed strength asymmetries, particularly in sports with unilateral movements, underline the need for sport-specific training approaches to address these imbalances. Conclusion: the study revealed that sport-specific training can lead to strength asymmetries within normal ranges, suggesting that they may not substantially induce muscular imbalances. However, the distinct H:Q ratio patterns in hybrid sports emphasise the need for customised training and rehabilitation strategies.