Anabolic hormone profiles in elite military men: Robust associations with age, stress, and fatigue
We recently established stable daily profiles of the anabolic hormones dehydroepiandrosterone (DHEA) and testosterone in 57 elite military men. In this follow-on study, we explored associations of salivary anabolic hormone profiles with demographic (i.e., age, body mass index [BMI]) and biobehavioral health indices (i.e., blood pressure, sleep, perceived stress, fatigue) via correlational models. Next, nuanced patterns were constructed using quartile splits followed by one-way analysis of variance and post hoc subgroup comparisons. Both DHEA (r range: −0.33 to −0.49) and testosterone (r range: −0.19 to −0.41) were inversely associated with age. Quartile comparisons revealed that age-related declines in DHEA were linear, curvilinear, or sigmoidal, depending on the summary parameter of interest. Anabolic hormone profiles did not associate with BMI, blood pressure, or sleep efficiency. Robust linear associations were observed between testosterone and perceived stress (r range: −0.29 to −0.36); concentration-dependent patterns were less discernible. Lower DHEA (r range: −0.22 to −0.30) and testosterone (r range: −0.22 to −0.36) concentrations associated with higher fatigue. Subsequent quartile comparisons suggested a concentration-dependent threshold with respect to evening testosterone. Specifically, those individuals within the lowest quartile (≤68.4 pg/mL) endorsed the highest fatigue of the four groups (p = 0.01), while the remaining three groups did not differ from each other. This study not only showed that anabolic hormone profiles have distinctive age trajectories, but are also valuable predictors of stress and fatigue in elite military men. This highlights the importance of routine monitoring of anabolic hormone profiles to sustain and optimize health and readiness in chronically stressed populations.