“Comparison of The Effects of Zig-Zag Run And Shuttle Run Training On 50-Meter Sprint Speed In Football Athletes”. COMPETITOR: Jurnal Pendidikan Kepelatihan Olahraga 18, no. 1 (May 1, 2026): 0151–0159. Accessed May 25, 2026. https://competitor.idjournal.eu/index.php/competitor/article/view/494.