Differences in Lower-Limb Muscle Strength and Motor Performance Between Regular Basketball Participants and Non-Participants Among Chinese Children Aged 9–10 Years

Background/Objectives: Previous studies have reported that Chinese elementary school children exhibit reduced lower-limb muscle strength, particularly hip abduction strength, compared to their Japanese counterparts. In this study, we examined the association of regular basketball participation with lower-limb muscle strength and motor performance in Chinese boys aged 9–10 years. Methods: A total of 97 boys in Grades 4–5 were recruited from public elementary schools and local basketball clubs in Shandong Province, China. Measurements included height, body weight, grip strength, hip adduction strength, hip abduction strength, toe grip strength, the side-step test (SST), and the timed-up-and-go test (TUGT). Participants were classified into three groups: a ≥1-year group (Grade 4: n = 19; Grade 5: n = 14), a <1-year group (Grade 4: n = 17; Grade 5: n = 14), and a control group (Grade 4: n = 18; Grade 5: n = 15). Results: After adjustment for grade, age, height, and body weight, both basketball groups showed significantly higher SST values than those of controls (adjusted differences: 3.078–4.649 repetitions; p < 0.05) and shorter TUGT times (0.642–0.779 s; p < 0.001). Grip strength was higher in the ≥1-year than the <1-year group (p = 0.010). No significant group effects were observed for hip adduction strength, hip abduction strength, or toe grip strength. Conclusions: In this cross-sectional study, regular basketball participation was associated with better agility and functional mobility performance in boys aged 9–10 years. These findings highlight the potential relevance of basketball-based multidirectional activities to the development of agility and functional mobility during childhood.