CHANGES IN LOWER LIMB BONE DENSITY IN YOUNG JUMPERS

ABSTRACT Introduction The research on the exercise effect on the human bone density and skeletal muscle content mainly focuses on the middle-aged and elderly population. However, few studies on different sports’ effects upon bone and muscle density in college students and adolescents. Objective Study the effect of physical training on bone density and lower limb jumping ability in young people. Methods The relationship between bone mineral density and lower limb jumping ability was analyzed by mathematical statistics. Male individuals aged 10-20 years were divided into the early adolescence group (n=26) and late adolescence group (n=37). According to training status, they were divided into preadolescent athletic group (n=11), non-athletic group (n=15); puberty athletic group (n=11) and non-athletic group (n=15). The following indicators were used: bone density, vertical jump test, continuous vertical jump test, RDJ index. Results Athletes’ bone mineral density (BMD) is related to their muscle strength. These results suggest a certain internal connection between the (BMD) of bone tissue and the development of muscle strength. Therefore, there is evidence of differences in lower limb bone mineral density and jumping ability between the two groups. Conclusion Bone mineral density in the lower limbs of adolescents is correlated with jumping ability. Exercise can help improve bone density in adolescents. Evidence level II; Therapeutic Studies - Investigating the results.

摘要
引言 现有关于运动对人体骨密度与骨骼肌含量影响的研究多聚焦于中老年人群，而针对大学生及青少年群体中不同运动对骨骼与肌肉密度影响的相关研究仍较为匮乏。
研究目的 探讨体能训练对青少年骨密度及下肢跳跃能力的影响。
研究方法 本研究通过数理统计方法分析骨密度与下肢跳跃能力之间的关联。研究对象为10至20岁的男性个体，按发育阶段分为青春早期组（n=26）与青春晚期组（n=37）；进一步依据训练状态划分为青春前期运动组（n=11）、非运动组（n=15），青春发育期运动组（n=11）与非运动组（n=15）。本次研究采用的检测指标包括：骨密度、垂直跳跃测试、连续垂直跳跃测试以及RDJ指数。
研究结果 运动员的骨密度（bone mineral density, BMD）与其肌肉力量存在关联。上述结果提示，骨组织的骨密度与肌肉力量发育之间存在一定内在联系；因此两组受试者的下肢骨密度与跳跃能力存在显著差异。
结论 青少年下肢骨密度与跳跃能力呈显著相关，运动可有效提升青少年的骨密度。本研究证据等级为II级，属于探究干预效果的治疗性研究。