2013-02-05-Too-much-TV-inactivity-linked-with-lower-sperm-counts_ST_U.xml
^$^The price of sloth may include a lower sperm count.
Healthy young men who watch a lot of TV or skimp on exercise have lower counts than guys who watch less or move more, a new study finds.
The study is small and does not prove cause and effect. But it adds to evidence that modern living may be contributing to possible declines in sperm counts in developed countries.
The findings also may offer some reassurance to active guys who have heard that exercise might decrease sperm counts, says Jorge Chavarro, a researcher at the Harvard School of Public Health and a co-author of the study published Monday in the British Journal of Sports Medicine.
"Most of the previous research has focused on endurance athletes," who may be under unusual stresses, Chavarro says.
The latest study included 189 college men, ages 18 to 22, from Rochester, N.Y. Among the results:
On the couch. Those who watched the most TV, more than 20 hours a week, had sperm counts 44% lower than those who watched none.
Working out. Those who exercised the most, more than 15 hours a week, had sperm counts 73% higher than those who exercised the least, fewer than five hours a week.
Fertility. Researchers could not say whether the differences would have any effect on fertility.
Obesity and high-fat diets have been linked to lower sperm counts in other studies. Researchers also have been looking into the effects of fertilizers, plastics and other environmental factors.
Yet some question whether sperm counts are falling at all: They blame inconsistent study designs and other factors for the reported declines.
To see more of USAToday.com, or to subscribe, go to http://www.usatoday.com
Copyright 2012 USA TODAY, a division of Gannett Co. Inc.