Purpose. The aim of the study was to assess the effects of strength training on the physical capacities of disabled persons with cervical spine injuries. Basic procedures. The study sample consisted of four disabled subjects with C4-C6 cervical spine injury, who were active Paralympic athletes (one swimmer and three wheelchair rugby players) from the Foundation of Active Rehabilitation. The study was carried out over a period of 15 months. The Biodex System 3 Pro isokinetic dynamometer and an arm cycloergometer were used for measurements. The measurements of muscle torques at the shoulder joint were carried out at 8-week intervals using the Biodex dynamometer. Main findings. The test results revealed a correlation between the body's physical endurance and strength capacities of subjects with cervical spine injuries. The "Upperton" strength training equipment modified for tetraplegics allowed maximal loading of the disabled athletes' shoulder girdle. Conclusions. Strength training improves the maximal force of arms in tetraplegics and positively affects their physical endurance. Tetraplegics can take advantage of strength training only by using hand-fixed weights, due to the limited function of arm flexors, including the greatly reduced hand gripping function. Strength training is an indispensable element of rehabilitation of tetraplegics.