Plasma testosterone during treadmill exercise

Abstract

Five male volunteers performed 20 min of steady-state submaximal exercise on a motor-driven treadmill at five intensities (30, 45, 60, 75, and 90% VO2 max) as well as several maximal aerobic capacity tests. Peripheral venous plasma testosterone concentrations increased above resting values in proportion to exercise intensity. However, this increase in plasma testosterone concentration was virtually equal in magnitude to the decrease in plasma volume observed consequent to the exercise bouts, resulting in no change in total testosterone contents. There was an unexpected anticipatory elevation in resting preexercise control testosterone concentration and content with increasing work intensity. The possibility that testosterone has a direct role in the organism's response to whole-body exercise is questioned.

Baseline cortisol moderates testosterone reactivity to women's intercollegiate athletic competition

“…C and T reactions to athletic competition may be related through their shared connection to the psychological experience of athletic competition. In the athletic contests included in this report, competition-related increases in T are seen regardless of match or race outcome (Table 1) Both C and T in plasma increase during non-competitive aerobic exercise in proportion to the intensity and/or duration of the workout e.g., [25][26][27]. Softball is a sport which, unlike all the others studied here, does not involve a sustained period of physical exertion.…”

Use of the Testosterone/Cortisol Ratio Variable in Sports

“…Similar to cortisol, testosterone levels increases linearly in response to physical exercise until a specific threshold of exercise intensity is reached, with peak concentrations generally occurring at the end of physical activity [32]. However, some studies have shown that there is a negative relationship between cortisol and testosterone under specific conditions.…”

A Review of Weight Control Strategies and Their Effects on the Regulation of Hormonal Balance

“…With regards to an acute bout of endurance training, cortisol normally increases with respect to exercise intensity [104–106], but the correlation is not necessarily linear [107]. Circulating cortisol concentrations have been demonstrated to increase in trained men after repeated 100m sprints [108] and increase in type 1 diabetics during and after sprinting exercises [109].…”