Biological aspects of salivary hormones in male half-marathon performance

Abstract

Physical effort is known to alter the blood levels of many hormones, but there are only a few studies about the biological changes of salivary hormones. The aim of this work was to determine whether salivary testosterone and salivary cortisol levels, measured two weeks before a half-marathon race, relate to running performance in male recreational athletes. A group of eleven male recreational athletes preparing for a half-marathon was included in the study. Saliva for testosterone and cortisol determinations was collected before and immediately after a 15-km training run, two weeks before the half-marathon. Individual official half-marathon times, expressed in hours, were used as a measure of performance. Mean testosterone concentrations were 1.07 +/- 0.33 nmol/l before the run and 0.88 +/- 0.35 nmol/l after the run (p lt 0.05). Mean cortisol concentrations were 12.28 +/- 8.46 nmol/l before the run and 38.08 +/- 19.63 nmol/l after the run (p lt 0.05). The pre-run salivary testosterone levels marginally correlated with the corresponding half-marathon running times (p=0.068, 95% bootstrap CI for slope -0.40 to -0.06). However, post-run salivary testosterone levels significantly correlated with the corresponding half-marathon running times (p=0.011, 95% bootstrap CI for slope -0.41 to -0.16), even considering correlations with the runners' age. Salivary cortisol levels, either pre- or post-run, did not correlate with the corresponding half-marathon running times. The results of this study suggest that post-exercise salivary testosterone levels could have the potential to predict performance in endurance running, at least in recreational athletes.