The researcher wanted to examine the implications of an aerobic swimming training program on the body composition, biochemical, and physical fitness variables of obese men aged 40-45 years. A sample size of 12 subjects was chosen, and they were put through a 12 weeks aquatic training program, 3-4 sessions every week, 45 minutes to 60 minutes in duration, with progressive intensity and the use of aquatic aids in order to increase muscular resistance. The findings indicated significant changes, which were found statistically significant after the intervention such as decreases in weight, body mass index, body fat percentage and mass and increases in fat-free mass and body density. Biochemical results showed low levels of glucose and insulin, high levels of testosterone and low levels of cortisol. There was also the improvement of the physical fitness indicators such as cardiorespiratory endurance, muscular endurance of upper and lower limbs and abdominal muscles. The researchers concluded that aerobic aquatic exercise is effective and safe and its benefits are holistic, encompassing body composition, biochemical markers as well as physical fitness and should be introduced in the physical rehabilitation and exercise programs.