The investigation into the maximal oxygen uptake provides the relevant data on the health of players, planning and follow-up of the training effects, also being useful for the early selection of athletes. For these reasons, the increase in VO2max values as indicators of physical capability of athletes is indispensable for achieving the top sports results. Our results show that the highest VO2max values were obtained in the football players, and that football as a sport requires higher degree of endurance compared to volleyball. Taking into consideration the morphological and functional changes as the consequence of the training process, it can be concluded that VO2max values are statistically significantly higher in the groups of athletes compared to the group of non-athletes.