Endocrine Biomarker Responses during an Intercollegiate Athletic Season

The current investigation aimed to quantify the endocrine biochemical markers including testosterone (T), cortisol (C), secretory immunoglobin A (sIgA) and testosterone:cortisol ratio (T:C) as indicators of the balance between anabolic and catabolic processes quantifying the homeostatic response to the late competitive phase of the college wrestling season in a longitudinal repeated measures, mixed design. A volunteer sample of ten elite (5 D1 All Americans) collegiate wrestlers (22.11 ± 1.1yrs, 177.8 ± 3.1cm; 77.6 ± 20.9kg) gave saliva samples via unstimulated passive drool (@0.75 mL) at 24 hours before competition and 24-48 hours post-competition. All biomarker concentrations were determined using indirect enzyme-linked immunosorbent assay (ELISA) kits. Time since awake for each sample, whether the team traveled, number of competitions (bouts), day of the study, and trial (pre vs. post) was recorded to test for effect and interactions on biomarker concentrations. A series of hierarchical linear models were utilized to conceptualize the change in T, C, T:C ratio and sIgA over the competitive season, a series of hierarchical linear models were used. Our analyses revealed both cortisol and testosterone concentrations were predicted by day of the study, time since awake, and the number of competitions; however, the T:C ratio was only predicted by day of the research and trial, indicating that as the season progressed, T:C ratio decreased over time after competitions.