Journal of Applied Physiology, Vol 69, Issue 1 196-200, Copyright © 1990 by American Physiological Society
Release of luteinizing hormone and growth hormone after recovery from maximal exercise
J. Y. Weltman, R. L. Seip, A. Weltman, D. Snead, W. S. Evans, J. D. Veldhuis and A. D. Rogol
Department of Pediatrics, Curry School of Education, University of Virginia, Charlottesville 22908.
Pulsatile properties of luteinizing hormone (LH) and growth hormone (GH)
release were evaluated in 19 eumenorrheic untrained females [mean age 31.1
+/- 1.1 yr, height 165.2 +/- 1.4 cm, weight 64.8 +/- 2.1 kg, peak oxygen
uptake (Vo2) 41.6 +/- 1.4 (SE) ml.kg-1.min-1] during the early follicular
phase of the menstrual cycle (days 3-4 after the onset of menses). Each
subject was studied during two consecutive menstrual cycles under each of
two conditions in random order: 1) no formal exercise for 72 h (C) and 2)
12-24 h after two maximal exercise bouts (peak Vo2/lactate threshold
treadmill evaluation and a 3,200-m time-trial run or a maximal Vo2 inclined
treadmill test) performed on consecutive days (EX). Blood sampling was
performed every 10 min for 12 h. LH and GH pulsatile parameters were
identified and characterized by the Cluster pulse detection algorithm. No
significant differences were noted in the number of peaks, peak amplitude,
interpeak interval, peak increment, or 12-h integrated concentrations
between C and EX for LH or GH. We conclude that maximal exercise protocols
typically used for exercise evaluation do not have an effect on the
pulsatile characteristics of LH or GH release in untrained women during the
early follicular phase of the menstrual cycle if 12-24 h of recovery are
allowed before evaluation of the pulsatile secretion of gonadotropins or
GH.
