A study on the effect of unilateral strength training intervention on lower limb asymmetry in college basketball players

Abstract Asymmetries in the limbs of athletes are common and can affect and limit athletic performance in training and competition, leading to a potential risk of injury.Improving asymmetries through targeted training can improve an athlete's performance and prevent injury.The aim of this study was to examine the presence of functional asymmetry in the lower limbs of young basketball players and to test whether a specific unilateral strength training programme was effective in reducing this asymmetry. Methods: mainly experimental and measurement methods are used.The study was conducted on 36 male participants of the Chinese University Basketball League, who were measured and evaluated for body size, strength and balance indexes. 18 athletes with lower limb asymmetry were randomly selected for a 12-week unilateral strength training intervention. Research findings: The test showed that the difference in the dimension and morphology of the upper and lower limb muscles of the male participants in the China University Basketball League tested was less than 2cm;Significant differences (p<0.05) in grip strength indicators between the right and left sides, and greater in the right hand than in the left;Significant differences in indicators of vertical ground reaction force and vertical upstroke between the left and right lower limbs in the single-leg vertical jump, with the left leg outperforming the right leg;In the Y-balance test, 53.16% of the subjects had a difference in anterolateral reach (>4cm) between the left and right sides, 55.89% had a difference in medial posterior reach (>6cm) between the left and right sides and 89.82% had a difference in lateral posterior reach (>6cm) between the left and right sides. Conclusion：(1) There is asymmetry of limbs in male participants of the China University Basketball League. The greatest differences in circumference indicators between the left and right sides of the upper and lower limbs were observed, while asymmetry in other indicators was not obvious. Asymmetry in strength indicators between the two sides of the limbs is mainly reflected in grip strength, dynamic balance ability and lower limb explosive strength.(2) 10 weeks of unilateral strength training was effective in improving lower limb explosive strength, maximal strength and quick strength, as well as lower limb asymmetry in male participants of the China University Basketball League.(3) The reduction of lower limb asymmetry in male participants in the China University Basketball League can significantly improve explosive power and balance. These results confirm that unilateral strength training exercises can counteract/reduce the degree of asymmetry in the lower limb strength of young basketball players.