The problem of evaluating and defining physical endurance of athletes has been the subject of a great body of research and scientific discussion. In team sports, especially football, the energy protection of working muscles in players requires the use of almost all metabolic pathways: aerobic, anaerobic and aerobic-anaerobic. Because of the varying pace of action, the share of energy conversions in muscle cells changes rapidly during a match. Another concern voiced by scientists and football coaches is the question of whether fitness training should always be performed with football balls. The aim of this paper was to present the necessity of monitoring the development of aerobic fitness in football players, and also to answer the question of whether motoric training in football may be performed with balls.