Hormonal responses to resistance exercise in long-term trained and untrained middle-aged men

J Strength Cond Res. 2008 Sep;22(5):1617-24. doi: 10.1519/JSC.0b013e31817bd45d.

Abstract

This cross-sectional study compared hormonal responses to resistance exercise between trained and untrained men to investigate the adaptations of the endocrine system to long-term strength training in middle-aged men. Twenty-one middle-aged men were recruited for this study and matched into a strength-trained group (SG) (n = 10) and an untrained group (UG) (n = 11). In the SG, the individuals had practiced strength training for hypertrophy for at least 3 years. Upper- and lower-body muscle strength was measured with a 1 repetition maximum (1RM) test. Blood samples were collected at rest and after multiple sets of a superset strength training protocol (SSTP), with an intensity of 75% of 1RM values. With these blood samples, the levels of total testosterone (TT), free testosterone (FT), dehydroepiandrosterone (DHEA), cortisol, and sex hormone-binding globulin (SHBG) were determined. In addition, the TT-to-cortisol ratio and TT-to-SHBG ratio were calculated. There was no difference at rest between groups in hormonal values for TT, FT, DHEA, cortisol, the TT-to-SHBG ratio, and the TT-to-cortisol ratio. There were increases after SSTP in the levels of TT, FT, DHEA, and cortisol and the TT-to-SHBG ratio in the UG, but only FT increased in the SG. The SG demonstrated lower values in the TT-to-SHBG ratio after the training session. These results suggest the presence of alterations in anabolic and catabolic hormonal responses to resistance exercise in long-term trained middle-aged men, with the trained subjects demonstrating lower responsiveness in the hormone values. Long-term trained men seem to require a higher volume of training, at least similar to their daily workout, to stimulate greater hormone responses.

MeSH terms

  • Adaptation, Physiological
  • Adult
  • Analysis of Variance
  • Biomarkers / blood*
  • Body Composition
  • Cross-Sectional Studies
  • Dehydroepiandrosterone / blood
  • Hormones / blood*
  • Humans
  • Hydrocortisone / blood
  • Male
  • Middle Aged
  • Muscle Strength / physiology
  • Resistance Training / methods*
  • Sex Hormone-Binding Globulin / metabolism
  • Testosterone / blood

Substances

  • Biomarkers
  • Hormones
  • Sex Hormone-Binding Globulin
  • Testosterone
  • Dehydroepiandrosterone
  • Hydrocortisone