Tsukahara Yuka, Namba Akira, Kamada Hiroshi, Torii Suguru, Tabata Shogo, Yamasawa Fumihiro, Sato Kazuki
Institute for Integrated Sports Medicine, Keio University School of Medicine, Tokyo, Japan.
Medical Committee, Japan Association of Athletics Federations (JAAF), Tokyo, Japan.
Am J Hum Biol. 2022 Feb;34(2):e23622. doi: 10.1002/ajhb.23622. Epub 2021 May 28.
The minimum body mass index (BMI) required to menarche and the relationship between the training onset age of sports and menarche is not fully understood. The aim of this study is to elucidate the minimum BMI required to attain menarche in female adolescent athletes competing at a national level, and to determine how the occurrence of menarche is associated with training onset age in track-and-field athletes.
Overall, 134 sprinters and 44 long-distance (LD) runners of ninth-grade females at a national level were enrolled and an anonymous questionnaire was administered.
As BMI increased, the proportion of athletes who had attained menarche increased. The BMI cutoff values for menarche were 17.3 and 17.1 kg/m for sprinters and LD runners, respectively. Menarche had not occurred in almost 50% of the LD runners who began training at elementary school, and among LD runners, those who began training at elementary school had 18.4 higher odds of not attaining menarche until the age of 15 years as opposed to those who started training after elementary school.
The BMI cutoff values could be an indicator for menarche in sprinters and LD runners. For LD runners, starting to compete at elementary school could be a risk factor for delayed menarche.
初潮所需的最低体重指数（BMI）以及运动训练起始年龄与初潮之间的关系尚未完全明确。本研究的目的是阐明在国家级比赛的女性青少年运动员中初潮所需的最低BMI，并确定初潮的发生与田径运动员训练起始年龄之间的关联。
总共招募了134名九年级国家级水平的女子短跑运动员和44名长跑运动员，并发放了匿名问卷。
随着BMI的增加，已初潮的运动员比例增加。短跑运动员和长跑运动员初潮的BMI临界值分别为17.3和17.1kg/m²。在小学就开始训练的长跑运动员中，近50%尚未初潮，并且在长跑运动员中，小学就开始训练的运动员在15岁时仍未初潮的几率比小学毕业后开始训练的运动员高18.4倍。
BMI临界值可作为短跑运动员和长跑运动员初潮的一个指标。对于长跑运动员来说，小学就开始参加比赛可能是初潮延迟的一个风险因素。
