Firas Abdul-hameed Khalid, Hatim Abdul-kareem Mohammed. The impact of competition effort on the vital capacity of football players according to the playing positions. ms [Internet]. 2021 Mar. 30 [cited 2024 May 5];20(1):0027-3. Available from: https://jcopew.uobaghdad.edu.iq/index.php/sport/article/view/620