Strenuous Workouts Impair Male Fertility

It is better to look than to procreate good? In some cases, that might be a win/win, but generally speaking, most men would rather be fertile than fit. Those men, or their wives, may want to take a close look at a study done at the University of Cordoba in Spain, showing that men who exercise to exhaustion
experience changes in their hormone levels and sperm counts. The Scientific American reports that the researchers assigned
16 healthy young men to either pedal to exhaustion on a special
exercise bike four times a week, or to avoid
intense physical activity. After two weeks, the exercisers showed a drop in their sperm concentration,
ejaculate volume, and the number of sperm per ejaculate, as
well as other changes in sperm quality. Their levels of two
other hormones — follicle stimulating hormone and luteinizing
hormone — fell, but remained within normal levels, while their
testosterone levels rose.
Sciam reports that two to three days after the training ended, hormone levels
and measures of sperm and semen quality and quality had
returned to near-normal levels among the exercisers. The researchers warn, however, that recovery might not be so quick
among older men.