ABSTRACT
The aim of our work was to increase the physical fitness by the determination of the optimal training intensity. In the physiological examination of ball-orientated games, the intermittent characteristic of the efforts is apparent. As football is a good example of that, we applied an intermittent exercise protocol, based on Mader's method (1980) developed for swimmers, for the longitudinal examination of footballers' physical fitness. Moreover, we studied the connection between the aerobic and anaerobic metabolism as well as the intensity of efforts.
