The results of the study cut right through the emotive question of whether players should have sex before matches, a controversial point among World Cup coaches and players, whose views differ widely.
While some coaches allowed wives to accompany players, Switzerland's British coach, Roy Hodgson, insisted that his squad bid farewell to wives before heading for the United States.
Doctors Mordechai Halperin and Alexander Olshanietsky, of the Israeli Impotence and Fertility Research Centre, not only give activity in the marital bed a warm embrace - 'take players' wives to the US but only let them make love at the right time' - they have drawn up a schedule of the most effective timing of sexual exertions for players in different positions. Playing positions, that is.
Their study of sports sexology suggests that goalkeepers and defenders need abstain only for three days before matches, midfielders for four days and strikers, whose scoring touch is more important on the pitch, for six days. However, a week without sex can make an attacker 'too aggressive' and lead to errors, Dr Olshanietsky suggested.
'Twenty minutes of dribbling uses up about the same amount of energy as sexual intercourse,' he said.
A female presence is a prerequisite to maintain 'the subtle mix of aggressivity and concentration' needed to win matches, the doctors found. That finding should give women's football quite a boost.Reuse content