Reactive Training in Enhancing Technical Performance and Modulating Cortisol Biomarkers in Competitive Soccer Players

: Centorbi, M, Medoro, A, Modolo, L, Di Claudio, G, Di Martino, G, Della Valle, C, Buonsenso, A, Marziliano, N, Davinelli, S, Calcagno, G, di Cagno, A, and Fiorilli, G. Reactive training in enhancing technical performance and modulating cortisol biomarkers in competitive soccer players. J Strength Cond Res XX(X): 000-000, 2026-In soccer, the ability to perceive, process, and integrate external and internal stimuli is crucial for the development of players' technical, physical, and tactical skills. This study aimed to assess the effectiveness of an Experimental Warm-Up (EWU) protocol for enhancing soccer-specific technical and physical skills while optimizing cortisol levels in elite soccer players. Thirty-two male soccer players (age: 24.7 ± 3.1 years) from 2 elite teams were assigned to an experimental group (EG; n = 18) or a control group (CG; n = 14). During the 12 weeks, along with their regular warm-up (WU), the EG performed an EWU consisting of 4 progressive coordination exercises, 4 times per week. The CG maintained their usual WU schedule. Technical abilities were assessed pre- and postintervention using the Y-Planned and Y-React, React Index (Y-REACT minus Y-PLAN), Illinois Change of Direction with and without ball (ICODT-BALL and ICODT), Technical Index (ICODT-BALL minus ICODT), and Loughborough Soccer Shooting (SHOT) tests. Urine samples were collected before and after the 12-week intervention to measure cortisol levels. The RM-ANOVA revealed significant improvements from pre- to postassessment in the EG for the ICODT-BALL, Technical Index, Y-REACT, React Index, and SHOT (p < 0.001). These improvements were significantly greater than those in the CG. In addition, the EG showed a significant reduction in cortisol levels from pre- to postintervention (p = 0.0007) and compared with the CG (p = 0.003). These findings indicate that incorporating coordinative training into WU improves technical performance and agility in soccer, supporting better regulation of cortisol levels in elite players.