The effect of stress, mental toughness, and their interaction on athletic and cognitive performance.

Athletes are regularly confronted with numerous challenges that contribute to elevated stress levels, which may interfere with optimal performance. Mental toughness (MT) is regarded as a crucial factor for athletic success, as it supports athletes in managing physical and psychological demands. Studies have reported positive associations between MT, adaptive coping strategies, reduced stress perception, and improved performance. The aim of the present study was to investigate the role of MT in moderating stress-performance relationship across three domains: physical endurance, cognitive performance, and isometric strength. Participants underwent a crossover design with two measurement timepoints in a randomized, counterbalanced order. In the stress condition, stress was induced using the Trier Social Stress Test, whereas in the control condition a documentary film was watched; both conditions were followed by a performance test on a bicycle ergometer (Study 1; n = 27), or the d2-R Test of Attention (Study 2; n = 27), and an isometric handgrip endurance task (Study 3; n = 28). Stress reactivity was measured by physiological and psychological parameters. Repeated measures ANCOVAs were conducted to examine the influence of MT and coping strategies. The results showed no significant interaction between MT and performance under stress. However, exploratory analyses indicated that athletes with higher MT used more problem-focused coping strategies, although no significant effect on performance was found across the three domains. These findings suggest that while MT is associated with coping preferences, its direct impact on the stress-performance relationship may depend on contextual factors, warranting further research in competitive settings.