Spinal muscular atrophy (SMA) shows a feature that the number of neuron in anterior horn of spinal cord and its function decline, and screening nerve in skeletal muscle and a gradual muscular atrophy are arisen by a fault in SMN gene (survival motor neuron gene). Through endurance exercise, it has been reported that the advancement of aerobic exercise capacity and protection for a nerve cell are effective, however. Therefore this study has been a single case study which has researched into type III SMA patient by carrying out 12-week combined exercise. As the participant, 17-year-old man (height: 161.0 cm, body weight: 47.2, BMI: 18.2) who has SMA III has taken part. He has done combined with exercise, which blends aerobic exercise and resistance exercise during 12 weeks. For measurement, aerobic exercise capacity by using body composition, physical fitness, and the arm ergometry and Isokinetic muscle function has been carried out. As the result, the muscle mass of arm and trunk in the body composition has grown by 10.5%, 7.6% and 5.6%. Continuous sprint has risen by 5.9% in the physical fitness. It``s shown that the result that VO2max and AT-VO2max has increased by 10.3% and 19.1% respectively in the aerobic exercise capacity, and the lactate level has been improved at the final time of exercise, too. In Isokinetic muscle function, the right side of the strength of extensor muscle at the whole of 60°/sec and 180°/sec shows a decreasing tendency, and the right side of the strength of flexor muscle and the left side of the strength of flexor and extensor muscle show the result that they has increased. Therefore, it also suggests that SMA patients should be able to make the aerobic exercise capacity and muscular strength improved a through continuous exercise.