The Effects of Training and Detraining on Metabolic Hormones in Rats

Abstract

PURPOSE We conclude that exercise training-induced effects in metabolic hormones continue for a prolonged period of detraining, but they are not associated with exercise intensity or detraining-induced increases in body weight.The purpose of this study was to examine the effect of diverse exercise training intensities, training periods and detraining periods on metabolic hormones. METHODS Eighty-four male Sprague-Dawley rats (aged 6 weeks, 173-200 g) were divided into 12 different groups by training, detraining, and control conditions. Exercise training consisted of low-intensity training and high-intensity training programs performed in the laboratory on a motor-driven rodent treadmill once per day, 5 days per week for 12 weeks. RESULTS Body weight significantly increased in all the conditions after the 12-week training period, with significant interaction among the conditions (p<.01). Body weights in the low-intensity trained detrained (LTD) and high-intensity trained detrained (HTD) groups were similar to those in the control groups after 6 weeks and 12 weeks of detraining (p<.05). There were significant differences in the hormones (leptin, insulin, and cortisol) between the control and trained detrained condition after 12 weeks of training, and 6 weeks and 12 weeks of detraining (p<.01), with no significant interaction between the trained detrained conditions (p<.05). CONCLUSIONS We conclude that exercise training-induced effects in metabolic hormones continue for a prolonged period of detraining, but they are not associated with exercise intensity or detraining-induced increases in body weight.

Keywords

• exercise training
• metabolism
• hormones