title: Comparisons of serum testosterone and corticosterone between exercise training during normoxia and hypobaric hypoxia in rats.
abstract: The purpose of this study was to compare the effects of continuous and intermittent exercise training on serum testosterone [T] and corticosterone concentrations [Cort] during normoxia and hypobaric hypoxia. Male rats swam with loads of 3% (normoxia) or 2.25% (462 mmHg) body mass for 60 min in the continuous training groups, and 15 min separated by a 7-min rest x 4, with 60-min total exercise duration in the intermittent training groups, 5 days week(-1) for 6 weeks. Serum [T] were measured at rest and following exercise after 6 weeks of training. Serum [Cort] were measured immediately after an acute period of exercise or after 6 weeks of training at rest and following exercise. Continuous exercise induced decreases in [T] under both conditions. Intermittent exercise showed a tendency to increase [T] during normoxia, but caused a suppression during hypobaric hypoxia. The [Cort] was elevated by a similar margin after an acute period of exercise during both conditions. After 6 weeks of training, however, [Cort] increased slightly after exercise during normoxia. A lower resting [Cort], which was increased after exercise, was found in the training groups during hypoxia. No relevant relationship was found between the behaviours of [T] and [Cort] after exercise during either conditions.
authors.affiliation: Department of Sports Physiology, Institute of Health and Sport Sciences, University of Tsukuba, Ibaraki, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Hu
authors.forename: K
authors.initials: K
authors.lastname: Asano
authors.forename: K
authors.initials: K
authors.lastname: Mizuno
authors.forename: S
authors.initials: S
authors.lastname: Usuki
authors.forename: Y
authors.initials: Y
authors.lastname: Kawakura
mesh_terms: D000818:Animals; D001274:Atmospheric Pressure; D003345:Corticosterone / Q000097:blood*; D000860:Hypoxia / Q000503:physiopathology*; D008297:Male; D010100:Oxygen / Q000494:pharmacology; D010805:Physical Conditioning, Animal / Q000502:physiology*; D005082:Physical Exertion / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D013739:Testosterone / Q000097:blood*
chemical_list: D013739:Testosterone; D010100:Oxygen; D003345:Corticosterone