Effects of body language training on mental health and performance in adolescent Ju Jutsu athletes

Background Competitive anxiety and psychological distress are prevalent in youth sports and can impair both mental health and performance. While psychological skills training is established, few interventions target athletes’ body language to reduce anxiety and improve confidence and performance. Aims This study examined the effects of a 12-week body language training program on competitive anxiety, psychological well-being, nonverbal behavior, and athletic performance in adolescent Ju-Jutsu athletes. Methods Fourteen athletes (14–18 years) were randomly assigned to an intervention (INT) or control group. INT included posture-focused nonverbal behavior training with daily posture exercises, sparring-based practice, and coach feedback. Pre- and post-intervention assessments included the Wettkampfangst-Inventar-State, the Depression Anxiety Stress Scale, video-based body language ratings, and competition performance. Data were analysed using ANCOVAs and mixed ANOVAs. Results For performance anxiety, significant group effects at post-test emerged for cognitive anxiety ( p = .005, η 2 = .53) and somatic anxiety ( p = .013, η 2 = .44), accompanied by a significant time × group interaction for self-confidence ( p = .01, η 2 = .43). Regarding psychological distress, significant group effects favored INT for total DASS-21 scores ( p = .004, η 2 = .23), depression ( p < .001, η 2 = .33), and stress ( p = .002, η 2 = .47), while general anxiety showed no significant group effect ( p = .41, η 2 = .03). Confident body language increased numerically but without significant group differences ( p = .227, η 2 = .08). Anxious body language decreased over time in both groups, without a significant intervention-specific effect ( p = .089, η 2 = .06). In competitive performance, INT showed a significant reduction in losses ( p = .019, η 2 = .41). Improvements in wins ( p = .06, η 2 = .27) and points per match ( p = .587, η 2 = .05) were observed within INT but were not supported by significant group-level effects after controlling for baseline values. Conclusions In this pilot randomized controlled trial, body language training was associated with reductions in performance anxiety, depressive symptoms, and stress, as well as improvements in selected competitive outcomes. Given the small sample size, these findings should be considered preliminary and require confirmation in adequately powered studies.