Shoulder complaints are frequently observed to result from the increased stress to the upper extremities of wheelchair users. The cause may be muscle dysbalances of the stressed musculature, whereby the changed situation in the wheelchair during everyday and athletic exercise is important. To demonstrate the different importance of altered shoulder stress in the wheelchair situation and in additional athletic stress, maximum strength in the dominant shoulder was recorded in 14 trained and 13 untrained paraplegics. The goal was to examine the differences between the groups during concentric (60 degrees/s) and eccentric (60 degrees/s) shoulder exercise. Based on the strength/velocity curve, differentiation was also made between the shoulder movements in dependence on various movement velocities. Finally, a comparison was to be made with the test results of untrained and trained, non-paralyzed subjects examined by the same test methods in earlier studies. The results show higher maximum torques in both groups under eccentric stress (p < 0.001), more expressed in trained paraplegics (p < 0.001). In group comparison, there are only slight differences in concentric exercise. The comparison between untrained paraplegics and untrained normal persons (non-paralyzed) show hardly any differences. Trained paraplegics attain values comparable to those of non-paralyzed athletes in eccentric and isometric shoulder exercise. It is concluded, that objective data for determination of the strength situation in the shoulder musculature can be obtained by isokinetic strength measurements in paraplegics. Obviously, eccentric forms of exercise are particularly important. Valuable information can be obtained by determining shoulder strength in dependence on work mode and comparison with non-paralyzed subjects; the information must be interpreted according to the movement.