Frainer, D. E. S., De-Oliveira, F. R., Abad, C. C. C. and Kiss, M. A. P. D. M. (2008) “Validity evidences in t20 as an approach to the anaerobic threshold in young soccer players”, Journal of Physical Education (Maringá), 15(2), pp. 33-37. Available at: https://periodicos.uem.br/ojs/index.php/RevEducFis/article/view/3419 (Accessed: 25December2025).