12~15岁青少年纵跳能力特征及其与身体形态的相关性

  目的  探讨12~15岁青少年纵跳能力的年龄与性别特征，分析纵跳能力与身体形态的相关性。  方法  采用区域分层方法选取中国9省(市)15所中学的12~15岁青少年1 280名，采用Smartjump纵跳测试系统测量半蹲跳高度(SJ-H)、下蹲跳高度(CMJ-H)、左腿下蹲跳高度(LCMJ-H)、右腿下蹲跳高度(RCMJ-H)，通过CMJ-H和SJ-H的比值计算出离心利用率(EUR)。测量受试者的身高、体重、体质量指数(BMI)、小腿围和足长5项身体形态指标。分析12~15岁青少年纵跳能力的年龄和性别特征，以及与身体形态指标间的相关性。  结果  男生纵跳高度随年龄增加而上升，12~15岁SJ-H(29.3~37.0 cm)、CMJ-H(30.8~39.9 cm)、LCMJ-H(15.1~19.2 cm)、RCMJ-H(14.8~18.9 cm)呈上升趋势。而女生纵跳高度仅有14与13岁之间差异有统计学意义，14岁SJ-H(25.3 cm)、CMJ-H(27.0 cm)高于13岁(24.5，26.1 cm)(t值分别为2.01，2.19，P值均 < 0.05)；男生SJ-H、CMJ-H、LCMJ-H、RCMJ-H均优于女生，且随着年龄的增长性别差异逐渐加大；EUR在各年龄男、女生间差异均无统计学意义(1.06~1.09)(t值分别为-0.11~0.94，P值均>0.05)；偏相关分析显示，全体12~15岁青少年SJ-H、CMJ-H、LCMJ-H、RCMJ-H与身高(r=0.38~0.43)、足长(r=0.22~0.29)存在中、低度相关，与体重(r=-0.17~-0.14)存在低度负相关(P值均 < 0.01)。  结论  12~15岁男生纵跳高度随年龄增加而上升，而女生14岁之后纵跳高度无增长趋势，12~15岁青少年纵跳能力与身高、体重、足长存在显著相关性；较大的体重对纵跳能力会产生限制作用。

Association of vertical jump performance with anthropological variables among adolescents aged 12-15

  Objective  To explore characteristics of vertical jump ability by age and gender and its correlation with anthropological variables among adolescents aged 12-15.  Methods  A total of 1 280 adolescents aged 12-15 years were recruited from 15 middle schools in 9 provinces and cities in China. The Smartjump contact mat, an assessing vertical jump system, was used to measure the squat jump height (SJ-H), countermovement jump height (CMJ-H), left-leg countermovement jump height (LCMJ-H) and right-leg countermovement jump height (RCMJ-H). The eccentric utilization ratio (EUR) was calculated as the ratio between CMJ-H and SJ-H. Data on height, weight, body mass index (BMI), calf circumference, and foot length of participants were collected. The differences in vertical jump ability by age and gender were compared by using a one-way ANOVA and the correlation between vertical jump ability and anthropological variables was analyzed by using a partial correlation analysis.  Results  The SJ-H (29.3-37.0 cm), CMJ-H (30.8-39.9 cm), LCMJ-H (15.1-19.2 cm) and RCMJ-H (14.8-18.9 cm) increased significantly with age among boys aged 12-15. But among girls, only the SJ-H and CMJ-H significantly increased in the 14-year-old group (SJ-H: 25.3 cm, CMJ-H: 27.0 cm) compared to the 13-year-old (24.5, 26.1 cm) (t=2.01, 2.19, P < 0.05). Additionally, boys performed better on the SJ-H, CMJ-H, LCMJ-H, and RCMJ-H, and this sex difference increased with age. There was no significant difference in EUR between boys and girls at different ages (1.06-1.09) (t=-0.11-0.94, P>0.05). The partial correlation analysis showed that SJ-H, CMJ-H, LCMJ-H, and RCMJ-H had low to moderate positive correlations with height (r=0.38-0.43), foot length (r=0.22-0.29) while low negative correlation with weight (r=-0.17-0.14)(P < 0.01).  Conclusion  The vertical jump performance increases with age among boys aged 12-15, while girls hardly increase until over the age of 14. The vertical jump performance is significantly associated with height, weight, and foot length and is restricted by greater weight among adolescents aged 12-15 years.