title: Long-term endurance training alters the hypothalamic-pituitary axes for gonadotropins and growth hormone.
abstract: In a prospective fashion we have studied the impact of chronic exercise of two intensities on the hypothalamic-pituitary-end organ axes for gonadotropins and GH in gynecologically mature, previously sedentary women. Physiologic alterations are evident in both axes with a doubling of 24-hour mean serum GH concentrations at 1 year and smaller, transient changes in pulsatile LH release during the first four menstrual cycles. The latter period of physiologic adaptation should be studied more intensively with more frequent exercise evaluation. Perhaps more significant "adaptation to stress" would be quantitated. We also emphasize that gynecologically less mature women were not studied and only the early follicular phase was evaluated. Adaptive changes of greater magnitude (including amenorrhea) might have been produced if a different group of women, a markedly different training regimen, or a different phase of the menstrual cycle were studied. Finally, whether or not they participate in physical training, younger amenorrheic women are at increased risk for diminished lumbar spine bone mineral content and skeletal fractures.
authors: Division of Pediatric Endocrinology, University of Virginia Health Sciences Center, Charlottesville.
authors: A D
authors: AD
authors: Rogol
authors: J Y
authors: JY
authors: Weltman
authors: W S
authors: WS
authors: Evans
authors: J D
authors: JD
authors: Veldhuis
authors: A L
authors: AL
authors: Weltman
mesh_terms: D015444:Exercise / Q000502:physiology*; D005260:Female; D006062:Gonadotropins / Q000096:biosynthesis*; D013006:Growth Hormone / Q000096:biosynthesis*; D006801:Humans; D007030:Hypothalamo-Hypophyseal System / Q000378:metabolism*; D008137:Longitudinal Studies; D008297:Male; D008597:Menstrual Cycle / Q000502:physiology; D011446:Prospective Studies
chemical_list: D006062:Gonadotropins; D013006:Growth Hormone