خلفة عماد الدين, and مزروع السعيد. “The Effect of a Gradual Muscle Relaxation Training Program on Relieving Psychological Stress to Improve the Level of Running Achievement Among Long-Distance Runners Less Than (17) Years ”. sports creativity 13, no. 01 (December 15, 2025): 133–154. Accessed February 4, 2026. https://journals.univ-msila.dz/index.php/JOSC/article/view/636.