中国青春期女生月经初潮较早与身体素质的关系

Association between early menarche and physical fitness among adolescent girls in China

目的分析中国青春期女生月经初潮较早与身体素质的相关关系。方法资料均来自2010年全国学生体质与健康调查数据，采用概率单位回归法计算月经初潮年龄的第10百分位数（P）概率界值，将界值以前已来月经者定义为月经初潮较早（9．0—11．6岁），共筛选出初潮较早女生1072名，按城乡、年龄（精确到0．1岁），以1：1频数匹配未来初潮女生，共1072名，并选取其50In跑、立定跳远、50m×8往返跑（7～12岁）、仰卧起坐4项身体素质指标。按年龄、城乡分层采用单水平t检验分析初潮较早组与未来潮组女生各项身体素质指标的差异；构建多水平单因变量和多因变量模型分析月经初潮较早与各项身体素质指标的关系。结果共纳入2144名学生，城市11．0～11．6岁组初潮较早女生的50m跑时间、立定跳远距离、仰卧起坐个数分别为（9．78±0．85）s、（153．81±18．59）cm、（27．79±10．25）个，未来潮学生分别为（10．ol±0．90）s、（149．71±18．72）cm、（26．28±10．11）个，差异均有统计学意义（t值分别为4．02、3．43、2．31，P值均〈0．01）；农村11．0～11．6岁组初潮较早女生50m×8往返跑时间、仰卧起坐个数分别为（120．924-13．06）s、（24．96±8．97）个，未来潮女生分别为（120．92±13．06）s、（22．96±9．83）个，差异均有统计学意义（t值分别为3．89、2．77，P值均〈0．01），10．0—10．9岁初潮较早、未来潮女生50m×8往返跑时间分别为（128．52±15．74）s、（123．89±13．50）S，差异有统计学意义（t=2．14，P〈0．05）。多水平分析结果显示，月经初潮较早女生50m跑时间、立定跳远距离、仰卧起坐个数分别比未来潮女生高0．12s、3．14cm、1．11个（WaldX。值分别为4．00、6．22、4．07，P值均〈0．05），而50in×8往返跑时间比未来潮学生低1．95S（Wald X2=3．96，P〈0．05）。结论中国青春期女生月经初潮较早可能与身体速度素质、爆发力素质、肌力素质增加及耐力素质下降有关。

Objective To explore the association between early menarche and physical fitness among adolescent girls in China. Methods Research material was selected from the data of ＂2010 National Physical Fitness and Health Survey＂. Probability unit regression method was used to calculate the age of 10th percentile at menarche and menarehe age before the 10th percentile was defined as early menarche （9.0 - 11.6 years old）. A total of 1072 girls with early menarche were selected. Each girl with early menarche was matched with one girl from the same urban or rural locations who hadn＇t achieved menarche with the age difference less than 0. 1 years. A total of 1072 girls without menarche were selected. Indicators of physical fitness included 50 m running, standing broad jump, 50 m × 8 shuttle running and sit-ups. Differences of physical fitness between early menarche and without menarche were analyzed using t test stratified by age and urban/rural area. The multilevel models of single dependent variable and multiple dependent variables were used to analyze association between early menarche and physical fitness. Results A total of 2144 students were put in this research. Among girls （ 11.0 - 11.6 years old） in urban areas, 50 m running, standing broad jump and sit-ups was （9.78 ± 0. 85 ） s, （ 153.81 ± 18.59） cm, and 27.79 ± 10. 25, respectively for those with early menarehe, while in girls without menarche was （ 10. 01 ± 0. 90） s, （ 149.71 ± 18.72 ）em and 26.28 ± 10. 11 , respectively. There were significant differences hetween two groups on all above variables （t values were 4. 02, 3.43 and 2.31 , respectively with all P values 〈 0. 01 ）. Among girls in rural, 50 m × 8 shuttle-running and sit-ups was （ 125.22 ± 15.57） s and 24.96 ±8.97 for those with early menarehe, while it was （ 120. 92 ± 13.06 ） s and 22. 96 ±9.83 for those without menarehe. There were significant differences between two groups on both variables（ t values were 3.89 and 2.77 with both P values 〈0. 01 ）. In addition, 50 m x8 shuttle-running in girls （ 10.0 - 10.9 years old） with early menarehe was （ 128.52 ± 15.74）s and it was（ 123.89 ± 13.50）s in girls without menarche. The difference was significant （t =2. 14, P 〈0.05 ）. The muhilevel analysis showed that 50 m running, standing broad jump and sit-ups in girls with early menarehe was 0. 12 s, 3. 14 em and 1. 11 higher than girls without menarehe （Waldx2 values were 4. 00, 6.22 and 4. 07 ,respectively with all P values 〈 0.05 ）. But 50 m × 8 shuttle-running in girls with early menarehe was 1.95 s less than girls without menarehe （ Waldx2 = 3.96, P 〈 0.05 ）. Conclusion Early menarehe may he associated with higher speed fitness, leg power and muscle power aru] lower physieal stamina.