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, vol. 13, no. 01, Dec. 2025, pp. 133-54, https://journals.univ-msila.dz/index.php/JOSC/article/view/636.