Sportsmen who produce electrical brainwaves of a certain frequency in the moments before a critical task - such as scoring a goal - are more likely than athletes who register few such brainwaves to succeed.
Researchers used electroencephalography, when electrodes placed on the head measure the brain's electrical activity, to study karate athletes breaking thick pieces of wood, football players taking penalties and cricketers 'stumping' the opposition.
In all three, the scientists detected marked differences in the brainwaves of sportsmen who were successful in the tasks and those who were not. Even in the same individuals, a high level of electrical activity was the necessary precondition for success.
David Collins, a sports scientist at Surrey University's St Mary's College in Twickenham, south-west London, said that in the karate athletes 'this effect was more pronounced for a harder task (breaking three inches of wood) than an easy task (1in) and its absence was associated with failure to break'.
The 'alpha' brainwave frequency appears to be the most important electrical activity associated with good concentration, he said. 'Increased attention to external stimuli results in alpha blocking. Thus the increases in alpha activity may be indicative of an inner focus of attention which is, in turn, associated with more effective task preparation.'
Dr Collins suggested that it may be possible to develop a reliable instrument to measure alpha brainwaves to help athletes train for mental as well as physical perfection. The researchers have also used psychological techniques to investigate aggression in sport. 'Athletes, particularly those in contact sports, are identified as commiting more violent crimes than the rest of the population, while anecdotes of the hostile, intent-to-harm mentality of players abound,' he said.
There has been great concern, especially in the United States, that certain sports encourage almost psychopathic behaviour. Some people have, for instance, wondered whether 'Mike Tyson is a nasty basket because he boxes', he said. Contact sports especially have been accused of either attracting people with violent tendencies or making people violent.
By comparing the emotional behaviour of athletes and non-athletes with psychological tests for aggressiveness, the researchers investigated whether certain athletes are more violent by nature and concluded this was not the case, Dr Collins said. 'The suggestion of psychopathic tendency in contact sportsmen should . . . be dismissed as scaremongering.'