Can salivary testosterone and cortisol reactivity to a mid-week stress test discriminate a match outcome during international rugby union competition?. Issue 3 (March 2018)

• Record Type: Journal Article
• Authors: Crewther, Blair T.; Potts, Neil; Kilduff, Liam P.; Drawer, Scott; Cook, Christian J.
• Is Part Of: Journal of science and medicine in sport. Volume 21:Issue 3(2018)
• Page Start: 312
• Page End: 316
• Publication Date: 2018-03
• Subjects: Sport -- Behaviour -- Readiness -- Training -- Neuroendocrine; Sports sciences -- Periodicals; Sports medicine -- Periodicals; Exercise -- Physiological aspects -- Periodicals; Sports -- physiology -- Periodicals; Sports Medicine -- Periodicals; Sportgeneeskunde; 617.102705
• DOI: 10.1016/j.jsams.2017.05.021
• Languages: English
• ISSNs: 1440-2440

Abstract

Abstract: Objectives: Evidence suggests that stress-induced changes in testosterone and cortisol are related to future competitive behaviours and team-sport outcomes. Therefore, we examined whether salivary testosterone and cortisol reactivity to a mid-week stress test can discriminate a match outcome in international rugby union competition. Design: Single group, quasi-experimental design with repeated measures. Method: Thirty-three male rugby players completed a standardised stress test three or four days before seven international matches. Stress testing involved seven minutes of shuttle runs (2 × 20 m), dispersed across one-minute stages with increasing speeds. Salivary testosterone and cortisol were measured in the morning, along with delta changes from morning to pre-test (Morn-PreΔ) and pre-test to post-test (Pre-PostΔ). Data were compared across wins (n = 3) and losses (n = 4). Results: The Morn-PreΔ in cortisol increased before winning and decreased prior to losing ( p < 0.001), with a large effect size difference ( d = 1.6, 90% CI 1.3–1.9). Testosterone decreased significantly across the same period, irrespective of the match outcome. The Morn-PreΔ in testosterone and cortisol, plus the Pre-PostΔ in testosterone, all predicted a match outcome ( p ≤ 0.01). The final model showed good diagnostic accuracy (72%) with cortisol as the main contributor. Conclusions: The salivary testosterone and cortisol responses to mid-week testing showed an ability to discriminate a rugby match outcome over a limited number of games. The Morn-PreΔ in cortisol was the strongest diagnostic biomarker. This model may provide a unique format to assess team readiness or recovery between competitions, especially with the emergence of rapid hormonal testing.