Keizer H A, Rogol A D
Department of Physiology, University of Limburg, Maastricht, The Netherlands.
Sports Med. 1990 Oct;10(4):218-35. doi: 10.2165/00007256-199010040-00002.
The prevalence of menstrual cycle alterations in athletes is considerably higher than in sedentary controls. There appears to be a multicausal aetiology, which makes it extremely difficult to dissociate the effects of physical exercise on the menstrual cycle from the other predisposing factors. From cross-sectional studies it appeared that physical training eventually might lead to shortening of the luteal phase and secondary amenorrhoea. Prospective studies in both trained and previously untrained women have shown that the amount and/or the intensity of exercise has to exceed a certain limit in order to elicit this phenomenon. We hypothesise, therefore, that apart from a certain predisposition, athletes with a training-induced altered menstrual cycle are overreached (short term overtraining, which is reversible in days to weeks after training reduction). Menstrual cycle alterations are most likely caused by subtle changes in the episodic secretion pattern of luteinising hormone (LH) as have been found in sedentary women with hypothalamic amenorrhoea as well as in athletes after very demanding training. The altered LH secretion then, might be caused by an increased corticotrophin-releasing hormone (CRH) secretion which inhibits the gonadotrophin-releasing hormone (GnRH) release. In addition, increased CRH tone will lead to increased beta-endorphin levels which will also inhibit the GnRH signaller. Finally, the continuous activation of the adrenals will result in a higher catecholamine production, which may be converted to catecholestrogens. These compounds are known to be potent inhibitors of GnRH secretion. In conclusion, menstrual cycle alterations are likely to occur after very demanding training, which causes an increase secretion of antireproductive hormones. These hormones can inhibit the normal pulsatile secretion pattern of the gonadotrophins.
运动员月经周期改变的发生率显著高于久坐不动的对照组。其病因似乎是多因素的，这使得将体育锻炼对月经周期的影响与其他诱发因素区分开来极为困难。横断面研究表明，体育训练最终可能导致黄体期缩短和继发性闭经。对受过训练和之前未受过训练的女性进行的前瞻性研究表明，运动量和/或运动强度必须超过一定限度才能引发这种现象。因此，我们推测，除了一定的易感性外，月经周期因训练而改变的运动员存在过度训练（短期过度训练，在减少训练后的数天至数周内可恢复）。月经周期改变很可能是由促黄体生成素（LH）脉冲式分泌模式的细微变化引起的，久坐的下丘脑性闭经女性以及经过高强度训练的运动员中也发现了这种变化。LH分泌的改变可能是由促肾上腺皮质激素释放激素（CRH）分泌增加引起的，CRH会抑制促性腺激素释放激素（GnRH）的释放。此外，CRH水平升高会导致β-内啡肽水平升高，这也会抑制GnRH信号传递。最后，肾上腺的持续激活会导致儿茶酚胺生成增加，儿茶酚胺可能会转化为儿茶酚雌激素。已知这些化合物是GnRH分泌的有效抑制剂。总之，可以推测，高强度训练后可能会出现月经周期改变，这会导致抗生殖激素分泌增加。这些激素会抑制促性腺激素正常的脉冲式分泌模式。
