Introduction. The aim of the study is to evaluate the metabolic and hormonal response of soccer players to maximum effort (test for determining anaerobic threshold changes - PPA) carried out under field conditions within a training cycle, which included a preparation period of about 7 weeks. Materials and methods. In blood samples of the 20 subjects the concentrations of lactate was determined, (LA) in whole blood, also including cortisol (C), testosterone (T) and growth hormone (GH) in blood plasma, during a running exercise performed according to the formula for determination of PPA. The heart rate (HR) was recorded during the running exercise. Threshold speed was determined based on OBLA. The tests were carried out twice: at the beginning and at the end of the seventh week preparatory period. Results. The training increased the threshold speed by an average of 0.4 m/s, lower concentrations of LA during the second test and less severe changes in HR. Endurance of the tested athletes increased at more favourable hormonal response with respect to cortisol nd and GH. The endurance component in the training, in the 2nd test resulted in lower resting testosterone levels, which did not affect the metabolic balance. The ratio of testosterone to cortisol (T/C), its growth after the period of training, showed a more stable anabolic-catabolic balance, which justifies the validity of the training assumptions in this period. Conclusions. The study confirmed the usefulness of metabolic-endocrine indicators in the monitoring the physiological response of athletes to exercise, as well as beneficial changes in the process of adaptation of bodies of athletes subjected to training.