Purpose. The goal of this thesis is to test the qualification of changes in balance as the effect of long-lasting balancing on a movable platform alternately in sagittal and frontal planes. It was expected to find answers to the following problems: 1. Does the effort caused by a 10-minute balancing in the given planes and in the given pattern have an influence on dynamic balance parameters? 2. Till which moment are the subjects able to improve their balancing skills in the given planes? 3. Do the possible changes progress in the same way in both planes considered? Basic procedures. 28 men aged between 24.3 and 33.8 years took part in this test. Average age of the subjects was 25.2 years. The tests were made on EasyTech Balance Platform. Tests consisted of a trial of balancing in a standing position with feet placed parallel on the platform. The subjects' task was to operate the platform through the right feet pressure to make the same sinusoid line as the pattern was. A ten-minute trial was made alternately in the sagittal and frontal planes. Individual dynamic parameters were recorded each minute of the test. Main findings. Significant improvement was noted in the first three minutes of the test. Between the 4th and 7th minutes parameters were relatively stable. The best results were recorded in the 8th minute of the test and this level was kept till the end of the trial. The character of the observed changes was analogous in the case of both planes. Conclusions. There was a statistically significant improvement in the dynamic body's stability noted in both planes in the test. Best results were recorded in the 8th minute of the test. The test used in the trial was long enough to establish the borderline between motor learning and the beginning of tiredness. The higher level of stability in the sagittal plane was affirmed in all successive minutes of the trials made.