Preliminary evidence of salivary cortisol predicting performance in a controlled setting.

The aims of this study were to examine the influence of salivary cortisol on tennis serve performance in a controlled setting and to investigate if cortisol predicts unique variance in performance beyond a subjective anxiety measure (i.e., Competitive State Anxiety Inventory-2 [CSAI-2]). Twenty-three tennis players performed two series of second tennis serves separated by an anxiety induction (i.e., arithmetic task). Cortisol was assessed six times during the experiment. Results show that cortisol response and a drop in serving performance are positively correlated (r=.68, p<.001). Cortisol also explains unique variance in performance (i.e., 19%) beyond CSAI-2 measures. Thus, considering cortisol measurements seems warranted in future research aimed at understanding performance.