From ThisisLondon.com via Fark

Scientists have shown there’s a reason men fall asleep after sex! Finally some empirical justice!

Why men fall asleep after sex
By David Wilkes, Daily Mail
17 February 2005

The gentle buzz of snoring is among the most annoying sounds known to woman. Especially when it happens shortly after a passionate encounter.

Yesterday scientists explained exactly why it is that men have a tendency to nod off after making love.

Apparently, it’s nothing to do with wanting to avoid a cosy chat with their partner. According to the scientists, they are simply tired out.

‘As frustrating as it is for most women that their male partners just roll over and fall asleep after sex, men aren’t entirely to blame,’ said Dr Neil Stanley, director of sleep at the University of Surrey.

‘Humans are the only animals in which sleep and sex are linked and while often seen as just a poor excuse, there are scientific reasons why men feel tired after sex.

‘The blood rush after climax depletes the muscles of energy-producing glycogen, leaving men feeling physically drained.

‘Because they have more muscle mass than women, men become tired after sex and this subsequently leads to them feeling sleepy.’

Eighty per cent of men said they felt more relaxed and were able to drift off without any problems after making love, compared with 46 per cent of women.

They were among 10,000 adults surveyed by organisers of The Vitality Show, Europe’s largest health and beauty exhibition.

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Not everyone nods off after sex. The survey found 48 per cent of men had actually fallen asleep during the act itself.

A mere 11 per cent of women admitted being guilty of this.