Exploring the Influence of Coherent Breathing on Psychophysiological Stress During a Simulated 3-Day 400-m Race

Chiron, F, Gulören, B, Erblang, M, Poirier, C, Elbaz, M, Servonnet, A, Gaudin, M, Le Coz, C, Lopes, P, Chennaoui, M, Hanon, C, Léger, D, and Thomas, C. Exploring the influence of coherent breathing on psychophysiological stress during a simulated 3-day 400-m race. J Strength Cond Res XX(X): 000–000, 2025—Managing psychophysiological stress is essential for elite athletes, especially during the high-intensity competitive period. Coherent breathing has been proposed as a noninvasive strategy to enhance recovery by modulating autonomic, neuroendocrine, and inflammatory responses. This study investigated the effects of coherent breathing on the autonomic nervous system (ANS), hypothalamic-pituitary-adrenal (HPA) axis regulation, inflammatory response, and sleep parameters in well-trained athletes undergoing repeated supramaximal efforts. Twenty-two athletes ( N = 22) were randomly assigned to a control group (CONT, n = 11) or a coherent breathing group (RELAX, n = 11). Over an 8-day protocol simulating competition, athletes completed 3 400-m races. Heart rate variability, salivary biomarkers (alpha-amylase, cortisol, testosterone IL1-β), and sleep parameters were assessed throughout this study. Two-way repeated measure ANOVA revealed that the RELAX group showed significantly increased parasympathetic activity (root mean square of successive difference, p < 0.01) and a more stable cortisol response ( p < 0.01) compared with the control group. The RELAX group also exhibited lower IL1-β levels ( p < 0.05), longer total sleep duration ( p < 0.05), and reduced sleep latency ( p < 0.05). No significant differences in athletic performance were observed between groups. Coherent breathing effectively modulates psychophysiological stress by enhancing ANS balance, regulating HPA axis activity, reducing inflammatory responses, and improving sleep quality. This accessible and low-cost intervention may support recovery and resilience in athletes exposed to repeated high-intensity efforts.