锻炼妇女月经紊乱的患病率很高。2003年,有人建议黄体生成素(LH)搏动性的破坏发生在30kcal/kgLBM/d的能量可用性(EA)阈值以下。本文对有关生殖轴中断和月经紊乱发生在建议阈值以下的理论的证据进行了严格审查。短期实验室研究表明,4-5天的EA低于30kcal/kgLBM/d,有或没有运动诱导,血清三碘甲状腺原氨酸和LH脉冲频率降低,久坐时LH脉冲振幅增加,经常来月经的妇女。较少的研究调查了长期暴露于低EA后的下游卵巢效应。SargentCamp研究是第一个诱发黄体期缺陷的随机试验,月经延迟,和无排卵,导致体重减轻(-4±0.3kg),两个月经周期的运动量突然增加。BioEnergetics研究是一项随机对照试验,通过操纵三个月经周期的能量摄入和消耗来诱导不同水平的能量缺乏。LH脉冲频率和三碘甲状腺原氨酸降低,57%的女性出现黄体期缺陷,无排卵,和/或月经过少。低于30kcal/kgFFM/d的EA会使经历月经紊乱的机会增加50%。然而,观察到月经紊乱高于和低于EA阈值,LH脉冲频率的变化只能预测黄体相缺陷,不是月经过少或无排卵。建议的EA阈值不是发生月经紊乱的截止值,但表示经历月经紊乱的风险增加。
Exercising women have a high prevalence of menstrual disturbances. In 2003, it was suggested that disruption in luteinizing hormone (LH) pulsatility occurs below a threshold of energy availability (EA) of 30 kcal/kg lean body mass (LBM)/day. This paper is a critical
review of the evidence regarding the theory that disruptions to the reproductive axis and menstrual disturbances occur below the proposed threshold. Short-term laboratory studies demonstrated that 4-5 days of an EA below 30 kcal/kg LBM/day, induced with or without exercise, decreased serum triiodothyronine and LH pulse frequency, and increased LH pulse amplitude in sedentary, regularly menstruating women. Fewer studies have investigated downstream ovarian effects after long-term exposure to low EA. The Sargent Camp Study was the first randomized trial that induced luteal phase defects, delayed menses, and anovulation by causing weight loss (-4 ± 0.3 kg) with an abrupt increase in exercise volume for two menstrual cycles. The BioEnergetics Study was a randomized controlled trial that induced varying levels of energy deficits by manipulating energy intake and expenditure for three menstrual cycles. LH pulse frequency and triiodothyronine decreased, and 57% of women developed luteal phase defects, anovulation, and/or oligomenorrhea. An EA below 30 kcal/kg fat free mass/day increased the chance of experiencing a menstrual disturbance by 50%. However, menstrual disturbances were observed above and below that EA threshold, and changes in LH pulse frequency predicted only luteal phase defects, not oligomenorrhea or anovulation. The proposed EA threshold is not a cut-off below which menstrual disturbances occur, but represents an increased risk of experiencing menstrual disturbances.