Androgenic Response to Long-Term Physical Training in Male Subjects

Abstract

An increase in endogenous androgen production has been observed following long-term physical training and the beneficial effects of training have been attributed in part to this phenomenon. Other investigators, however, found, in contrast lower testosterone levels in trained compared with untrained subjects. The purpose of the present study was to follow the long-term changes in total testosterone (T) and cortisol (C) levels in intensely training individuals. The changes in the body's anabolic state, induced by intense long-term physical training, were determined using the plasma resting T/C ratio. T and C levels of 35 young untrained subjects were measured at 6 week intervals during 18 weeks of strenuous physical training. All samples were drawn within one half hour of awaking (05.30-06.00). Mean serum T levels increased significantly at 6 weeks (28.7%, p less than 0.02) and decreased significantly at 12 weeks (20.6%, p less than 0.02), but did not differ at 18 weeks compared with levels before training was commenced (mean +/- SE, 16.9 +/- 0.2, 21.8 +/- 0.3, 12.8 +/- 0.2 and 17.3 +/- 0.2 nmol/l at 0, 6, 12, and 18 weeks, respectively). Mean serum C was increased significantly (21.3%, p less than 0.005) at 18 weeks (463.5 +/- 19.3, 507.7 +/- 22.1, 480.1 +/- 19.3, and 565.6 +/- 22.1 nmol/l). T/C ratio decreased significantly after 12 and 18 weeks of training. Our results do not support an association between reduced total testosterone levels and prolonged training. However, hypercorticolism with a relative catabolic state may occur.

Hormonal responses to a 160-km race across frozen Alaska

“…Similarly, other researchers have found resting levels of cortisol in endurance-trained athletes to be similar to untrained people 35 36. Nevertheless, some researchers have speculated that raised cortisol levels, as a direct consequence of endurance training37 and more specifically overtraining,38 is a plausible mechanism to explain low basal testosterone. However, in our investigation, it is unlikely that our athletes were overtrained, and the training of these athletes was not a significant source of physical stress inducing raised resting cortisol levels.…”

Salivary Cortisol and Testosterone Variations during an Official and a Simulated Weight-Lifting Competition

“…Many researchers have studied this ratio in order to find out the influence of strength training on the anabolic and catabolic hormone balance (2.3. 5,8,17,18,21,32,37,41,43). Certain authors believe that the FTCR (Free Testosterone/Cortisol Ratio) threshold below 0.35. lo-' found in plasma could indicate an overtraining (2).…”

Effects of chronic intensive training on androgenic and cortisol profiles in premenarchal female gymnasts

“…Studies carried out in adults suggest that high levels of physical activity result in changes in the secretion of androgens and cortisol in both men (Adlercreutz et al 1986;Guezennec et al 1986;Hackney et al 1990;Seidman et al 1990) and in women (Bonen and Keizer 1987;Filaire and Lac 2000). These changes are dependent upon the intensity and duration of exercise, and the training experience of the subjects and type of exercise performed (De Souza et al 1994;Lac et al 1995).…”