Interpreting cortisol and testosterone: are they markers of readiness to perform?

Readiness in sport is a topic of interest for many coaches, athletes, and performance support staff alike. In the context of hormones, it has been viewed as a response to stress (i.e. increasing free cortisol and testosterone). However, whether a causal relationship exists for cortisol and testosterone with performance remains unclear. Free cortisol and testosterone possibly remain best viewed as relevant biomarkers of the stress response, with this response also being, in part, a proxy measure of readiness. The priming of cortisol and testosterone through exercise, warm-up, or other stimuli to prepare for performance has been a recurring theme amongst research; however, the results in terms of both the magnitude of hormone change and influence on subsequent performance are highly variable. In fact, cortisol and testosterone change in the context of readiness appears individual in nature and are affected by physiology, training status, age, sex, trained state, and individuals' perceptions of both their liking and the magnitude of the stressor. The importance of individuality in this context is poorly understood, and an opportunity exists to undertake research to increase the understanding and application of strategies that may enhance readiness to perform in females and males.