Watching football could be good for a man's sex life - providing his team wins, according to research showing differences in testosterone levels between opposing spectators.
Levels of testosterone, the male sex hormone associated with virility and aggression, increased by more than 25 per cent in men who watched their side win. Men on the losing side suffered an equally significant decline.
The results of the research, soon to be published in the scientific press, will add fuel to the debate over whether raised levels of testosterone in football fans increases their tendency towards post-match aggression and possibly sexual arousal.
Scientists carried out the research on two groups of men while they watched last year's World Cup final between Brazil and Italy. They took saliva samples - which were later analysed for testosterone - before and after the game, which Brazil won on penalties.
The researchers, from Georgia State University, found that the average testosterone levels of the Brazilian fans increased by 27.6 per cent, compared to a 26.7 per cent decrease in the Italian men.
``Testosterone, and the feeling of power associated with it, increases as subjects bask in reflected glory and decreases as they experience vicarious defeat,'' Julie Fielden and Candice Lutter, the two psychologists who ran the experiment, say in their report on the work.
The researchers observed clear differences in behaviour between the two groups of fans after the game. ``Some Brazilians were arrested for riotous celebration in the streets. The Italian men looked depressed and apathetic. They were disheartened by the loss and several had to be pursued into the parking lot by the experimenter to collect post-game samples.''
Football results, page 23
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