The study included 44 men with 28 of them were overweight or obese and 16 had weight within a norm. None of them performed regular exercises before. After a 12-week program of cardio exercises, the scientist noticed the highest increase of testosterone levels in overweight or obese men who exercised most vigorously.
Hiroshi Kumagai, a lead researcher of the study, says: “So, it seems the increase in physical activity, especially vigorous physical activity, is the main factor for increasing serum testosterone levels.”
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