Acute hormonal responses to heavy resistance exercise in younger and older men

• Published in: European journal of applied physiology 1998-02, Vol.77 (3), p.206-211
• Main Authors: KRAEMER, W. J, HÄKKINEN, K, FARRELL, P. A, EVANS, W. J, NEWTON, R. U, MCCORMICK, M, NINDL, B. C, VOLEK, J. S, GOTSHALK, L. A, FLECK, S. J, CAMPBELL, W. W, GORDON, S. E
• Format: Article
• Language: English
• Subjects: Adrenocorticotropic Hormone - blood; Adult; Aging - physiology; Biological and medical sciences; Blood Glucose - metabolism; Fundamental and applied biological sciences. Psychology; Hormones - blood; Human Growth Hormone - blood; Humans; Hydrocortisone - blood; Insulin - blood; Lactic Acid - blood; Male; Middle Aged; Space life sciences; Testosterone - blood; Vertebrates: body movement. Posture. Locomotion. Flight. Swimming. Physical exercise. Rest. Sports; Weight Lifting - physiology
• ISSN: 0301-5548; 1439-6319; 1432-1025; 1439-6327
• DOI: 10.1007/s004210050323

The purpose of this investigation was to examine the acute responses of several hormones [total and free testosterone (TT and FT, respectively), adrenocorticotropic hormone (ACTH), cortisol (C), growth hormone (GH), and insulin (INS)] to a single bout of heavy resistance exercise (HRE). Eight younger [30-year (30y) group] and nine older [62-year (62y) group] men matched for general physical characteristics and activity levels performed four sets of ten repetitions maximum (RM) squats with 90 s rest between sets. Blood samples were obtained from each subject via an indwelling cannula with a saline lock pre-exercise, immediately post-exercise (IP), and 5, 15 and 30 min post-exercise. Levels of TT, FT, ACTH, C and lactate significantly increased after HRE for both groups. Pre-HRE pairwise differences between groups were noted only for FT, while post-HRE pairwise differences were found for TT, FT, GH, glucose and lactate. Area under the curve analysis showed that the 30y group had a significantly higher magnitude of increase over the entire recovery period (IP, 5, 15, and 30 min post-exercise) for TT, FT, ACTH and GH. Few changes occurred in the INS response with the only change being that the 62y group demonstrated a decrease IP. Lactate remained elevated at 30 min post-HRE. This investigation demonstrates that age-related differences occur in the endocrine response to HRE, and the most striking changes appear evident in the FT response to HRE in physically active young and older men.