The effect of hypoxic exercises using an altitude training mask on the strength and extensibility of the respiratory muscles to call for physical effort among young soccer players. Al-Rafidain Journal For Sport Sciences, [S. l.], v. 29, n. 90, p. 30–43, 2026. DOI: 10.33899/rjss.v29i90.62565. Disponível em: https://rsprs.uomosul.edu.iq/index.php/rsprs/article/view/62565. Acesso em: 24 jun. 2026.