خلفة عا, مزروع ا. 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 . (J. Spo. Creativity) [Internet]. 2025 Dec. 15 [cited 2026 Feb. 4];13(01):133-54. Available from: https://journals.univ-msila.dz/index.php/JOSC/article/view/636