Regular aerobic exercise decreases circulating estradiol/testosterone ratio in overweight and obese men

The ratio of circulating estradiol to testosterone has been identified as a powerful predictor of cardiovascular disease in men. Obesity results in an increased circulating estradiol/testosterone ratio and is a high risk of cardiovascular disease. Aerobic exercise is a well-known preventive and effective strategy for the treatment of cardiovascular disease. However, the effect of regular aerobic exercise on the circulating estradiol/testosterone ratio in overweight and obese men has not been clarified. The present study aimed to investigate the effect of a 12-week aerobic exercise program on the circulating estradiol/testosterone ratio in overweight and obese men. Fifteen overweight and obese men (mean age, 46 ± 3 years; body mass index, 28.7 ± 1.0 kg/m2) completed a 12-week aerobic exercise intervention (90 min/session, one to three sessions/week). Before and after the intervention, we measured the circulating levels of estradiol and testosterone and calculated the estradiol/testosterone ratio in overweight and obese men. After the intervention, serum testosterone levels increased significantly (p < 0.05), whereas plasma estradiol levels did not change significantly. The circulating estradiol/testosterone ratio significantly decreased after the 12-week aerobic exercise intervention (p < 0.05). These results suggest that 12-week aerobic exercise decreases the circulating estradiol/testosterone ratio as a predictor of cardiovascular disease and reflects the decrease in the risk of cardiovascular disease in overweight and obese men.