Purpose. In most circumstances it is possible to provide the precise estimation of force and weight by means of kinesthetic differentiation. In some conditions, like physical effort or fatigue, kinesthetic differentiation can become reduced. The kinesthetic differentiation capacity can be expressed as repeatability of muscular contraction force or movement. The present study investigates the direction of changes in kinesthetic differentiation of force applied by both arms during elbow flexion and extension before and after exercise. Basic procedures. The study sample consisted of 23 cyclists (mean ± SD) aged 18.1 ± 1.8 years, 17 rowers aged 18.1 ± 1.8 years, and a control group consisting of 32 subjects aged 21.3 ± 1.3 years. All subjects performed a progressive exercise test. Kinesthetic differentiation was measured as the repeatability of force applied during elbow flexion and extension. Main findings. The results obtained confirm that kinesthetic differentiation in both arms after exercise improved by means of elbow extension. Further research can contribute to the development of ways of control of adaptation changes in the central nervous system and the locomotor system on a general level, since the studies so far have described either local changes, e.g. EMG, or provided specific data related to typical patterns of activity in a given sport. Conclusions. The proposed method allows identification of effects of intense exercise on the kinesthetic differentiation capacity on a more general level.