韓国女子スポーツ選手における BMI の加齢変化から導かれる身体的ストレス性初経遅延の模索

抄録

This study derived the changes in BMI with age in general South Korean girls compared with female athletes using the wavelet interpolation method, and investigated the critical stage of fat percentage for the onset of menarche. It also investigated the relationship between maximum peak velocity (MPV) of BMI and age at menarche, assuming that the critical stage is near the age of MPV on the aging velocity curve of BMI. Then, by comparing the interval between age at menarche and age at MPV derived from changes with age in BMI in Korean female athletes, the delay in menarche from stress was investigated. Age at menarche, menstrual cycle, and menstrual status were surveyed in second-year students at a girls' physical education high school in Busan (athletes). Next, longitudinal growth data for height and weight were obtained from the first year of elementary school until the second year of high school. Four hundred third-year female students at regular high schools in the suburbs of Busan were selected for the control group (non-athletes), and were surveyed using the same methods as the athletes. Finally, the data for 77 athletes and 232 controls were used. Wavelet interpolation was applied to BMI values calculated from growth distance values for height and weight from age 7 to 17 years in the athlete and control groups of Korean girls. The age at MPV of BMI was identified from growth curves derived by differentiating the individual aging distance curves for BMI in both groups. Then, the interval between age at MPV of BMI and age at menarche were calculated individually. In the control group the age at MPV of BMI was 11.72±1.55 years and the age at menarche was 12.25±0.95 years. Thus, the age at menarche was slightly earlier. In the athletes, the age at MPV of BMI was 11.84±1.36 years and the age at menarche was 13.37±1.37 years, showing a later age at menarche. The interval between MPV age at BMI and age at menarche was 0.53±1.62 years in the control group and 1.46±1.87 years in the athlete group. Thus, a significant difference (p<0.01) was seen between the groups, suggesting delayed menarche as a stress factor in athletes.