Men who watch three or more hours of television a day are half as fertile as those who rarely sit in front of the box.
Research, conducted by Harvard University, found that men who exercised for 15 hours or more a week had sperm counts that were 73% higher than those who exercised for less than five hours.
The findings, published in the British Journal of Sports Medicine, also discovered that dads-to-be who watched 20 hours or more of television a week had sperm counts 44% lower than those who watched very little.
“Being physically active increases the exposure of antioxidant enzymes, which we know increases sperm count,” said Jorge Chavarro, assistant professor of nutrition and epidemiology.
“Being inactive is the opposite. It’s related to high levels of oxidative stress, which is related to poor sperm production.”
The study is based on the findings from 189 college students aged 18 to 22.
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