Health Update: Fit for fatherhood

Men who are trying to father children should avoid strenuous exercise, according to a recent study from the US. Researchers writing in Fertility and Sterility found that when fit men doubled their usual training programmes for two weeks, their sperm counts dropped by 43 per cent. After three months, sperm counts were 52 per cent lower.

The researchers suggest that the fall in testosterone levels after exercise could affect the production of sperm for several months.