In this article we compared the effects of 9 months of judo training (JT; N = 41) and recreational sports games training (SGT; N = 57) on the fitness development of 7-year-old boys. Both programs were performed three times per week. Apart from body height, body weight, and skinfold thickness (SUM2SF), changes in muscular and cardiovascular endurance, flexibility, speed, agility, and coordination were studied. Using the analysis of variance, we found no differences between the groups at study entry, but after 9 months the JT participants achieved significantly better results in the shuttle-run task to test agility, the sit-up test for abdominal muscle endurance, and the sit-and-reach test for flexibility. The JT group also maintained their SUM2SF over the 9-month period, whereas the SGT group showed a significant increase in SUM2SF. No differences were observed between the groups in coordination, flexibility of the shoulder joint, speed, endurance, body height, and body weight. In conclusion, the specialized JT allowed the participants to improve more of their fitness capacities compared with nonspecialized SGT.