Abstract This master’s thesis is done by request of the C.A.M.O. Paintball (Ry) non-profit making association. The goal of this research is to find out the physical load of playing paintball and the levels of aerobic exercise. We present the paintball as a game, little bit of its history and basic idea of the game. As background knowledge we present the different levels of aerobic exercise zones. We use the heart rate variability measurement technique in our research. Whit this measurement we can point out the physical load, energy consumption and the individual training responses during the game time. There were 11 test persons in our research. Test persons were not professional players and the age distribution was between15-47. We used three different paintball fields. We present the test per-sons and the measurement reports. This master’s thesis is groundwork for measuring physical load of playing paintball. Whit this research we were able to get tentative information about the physical side of the players of paintball. In summary we can make this kind of results. Paintball game makes the players physical capacity better. It was promoting their health really well and energy consump-tion was massive. Players can contribute for their game by the activity levels and by the game roles. We hope that our research will bring out some thoughts about paintball as a sport.