Introduction. Skin is the largest organ of the human body. It plays an important role in protection against harmful substances found in the surrounding environment and takes part in the elimination of heavy metals from the body by sweating. The aim of the study was to evaluate the changes in the concentration of lead and copper in the sweat collected on the first and the fourteenth day of endurance training. Materials and methods. The research included 43 patients undergoing a supervised, two-week endurance training on a cycle ergometer and cross-trainer. The lead and copper contents were presented in relation to the sodium content as an indicator of the amount of excreted sweat. Results. The lead concentration in relation to the sodium content in the samples of sweat taken with the use of swabs is statistically significantly higher on day 1 (Me = 1.64-E-4) than the 14th day (Me = 0.37-E-4) p = 0.027. In the sweat samples collected with a plaster, the lead concentration on day 14 of rehabilitation (Me = 0.08-E-4) is statistically significantly lower than before the beginning of the training cycle (Me = 1.19-E-4) p = 0.044. The concentration of copper in sweat samples collected with swabs and patches on day 1 of the rehabilitation cycle does not significantly differ from the content of samples collected on day 14. Conclusions. Endurance training with submaximal heart rate results in reduced excretion of lead in the sweat and does not significantly affect the level of copper. Further research into the impact of physical effort on the excretion of metals from the body can help explain the results.