Hormonal Responses to Resistance Exercise in Long-Term Trained and Untrained Middle-Aged Men

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.

Six weeks of conditioning exercise increases total, but not free testosterone in lifelong sedentary aging men

“…Acute exercise-induced increases in T concentrations have been widely reported [13][14][15][16][17]. However, despite exercise being a commonly used first-line treatment for mild ageassociated T decrements [18,19], it remains unclear whether exercise can potentiate a reversal of the age-associated decline in systemic androgens.…”

DHEA, DHEA-S and cortisol responses to acute exercise in older adults in relation to exercise training status and sex

“…endurance trained young males showed attenuated increases in hormone concentrations in response to exercise compared to resistance-trained individuals (Tremblay et al 2004). One study has compared hormonal responses to resistance exercise in middleaged strength-trained and untrained men (Cadore et al 2008). There were no differences in hormones between trained and untrained men at rest; however, untrained men demonstrated a significant increase in DHEA and cortisol in response to acute resistance exercise, where trained men did not.…”

Effects of the Occlusal Thickness of Mouthpieces on Salivary Cortisol during Resistance Strength Training

“…Other studies have shown that cortisol concentrations increase either immediately following commencement of exercise [28][29][30][31] or at 15 min into rest [32], with cortisol concentrations returning to baseline anywhere from 30 min [32] to 3 hours following commencement of exercise [31]. Larger increases in post-exercise cortisol concentrations and elongated cortisol recovery times were associated with highintensity exercise of a greater duration.…”