Fitness fanatics are aggressive

London: Fitness fanatics are more likely to be aggressive, dominant and highly sexed, according to scientists who have identified a link between exercise and personality.

Their findings confirm the old stereotype of muscle-bound bullies kicking sand in the faces of nerdy people who spend more of their spare time in front of a screen rather than the gym, reports a website.

This suggests a link between a person`s personality and their ability to generate energy, said the joint study by universities in New South Wales in Australia and California, in the US.

It may also explain why some animals in captivity continue to exercise even though they do not need to in order to eat or survive.

Australian professor Peter Biro who wrote the report said it showed a link between personality and energy levels.

"Some of us are couch potatoes while others are drawn to sport and exercise. We often associate the athletic `jock` type or person with being aggressive and social, whereas the more sedentary `nerd` often is seen as more socially awkward and submissive," he said.

"These are generalisations, but most people would probably agree there is some truth to them," he added.

Studies suggest personality is linked to metabolism, the chemical process that converts food into energy and fuels the body.

"There are also several species of fish and birds where those with a higher metabolism exhibit more aggression and tend to dominate those with a lower metabolic rate," said Biro.

"It may just be that some individuals generate much more energy than others. We are still some ways from a really solid understanding of the links between metabolism and personality, but recent research suggests these ideas have merit and are worth studying further," he added.