WHEN Scots athlete Jayne Nisbet took part in the final of the Commonwealth Games high jump competition, it marked the end of a long struggle back to fitness after suffering bulimia.

Now leading UK sports bodies have set up a dedicated group to try to address the issue of eating disorders among mostly female athletes, the Sunday Herald can reveal.

The working group involves several bodies including UK Sport, which invests in high-performance sport, and UK Athletics, and is being co-ordinated by the Child Protection in Sport Unit.

Studies have suggested that just over 20% of female athletes from all disciplines suffer from an eating disorder - more than double the rate in non-athletes. Men are also affected, and while prevalence is lower at 8%, that figure is 16 times the rate seen in non-sporting men.

Nisbet spoke of her battle in overcoming bulimia ahead of taking part in the final of the high jump competition on Friday, and told how the disease caused her to miss out on competing in the Commonwealth Games in Delhi in 2010 and highlighted the pressure felt by female athletes about their appearance.

"You are striving to achieve and you can get caught up in different things. I have seen it happen in so many people," she said.

She said she believed she had to lose weight to be on a par with fellow competitors and jump higher. Instead it resulted in her performances worsening and it took two years to build back up to achieve her personal best again.

She added: "You are wearing a crop top and pants on TV, if you are a little bit overweight you are going to get criticised."

The sports which have been identified as most "high risk" for eating disorders include swimming, running, gymnastics, diving, wrestling and judo, due to the athlete either having their body on display, or the sport demanding athletes hit particular weights to compete.

Guidelines produced by UK Sport on the issue note that the normal eating habits of athletes may appear extreme to the non-sporting, but more unusual attitudes can lead to a full-blown eating disorder.

These include "disordered eating", characterised by a restrictive or faddy diet, plus excessive exercise; anorexia athletica, where there is a fear of weight gain although the person is already lean; and bulimia nervosa, marked by recurring binge eating and purging.

Dr Alan Currie, a Scottish consultant psychiatrist based in Northumberland and a trustee of eating disorder charity Beat, said the issue of appearance was only one possible causal factor for eating disorders among athletes, which could also include general background reasons such as a person's psychological make-up.

But he said: "The sports environment adds additional risks, and it varies from sport to sport. For example, in endurance sports like running, there is a relationship between weight and performance - for most people if they are a bit lighter, their endurance capacity is better. A 16-stone man running a marathon has got a lot of weight to carry around 26 miles - if he was 10.5 stone he would be great.

"But if you carry on in that cycle of losing weight to improve your performance then you will come unstuck and that might descend into an eating disorder."

Currie said that sports where athletes had to compete within weight categories, such as judo, wrestling and boxing, could also put competitors at risk of "bulimic-type" behaviours.

Aesthetic sports where there is judgment on appearance - such as gymnastics and diving - combined with wearing revealing outfits were also more likely to have higher rates of eating disorders, he said.

Currie said: "An additional risk might be that if you want to identify a problem early, it is relatively speaking harder to spot someone who is over-exercising and who is unhealthily lean among a group of athletes.

"If you want to spot someone who has got anorexia nervosa and you are looking along a bus queue, it is probably quite easy to pick out the person who is really lean - but on the start line of, say, a 1500m race?"

He added: "People have also commented on the psychological similarities between a good anorexic and a driven perfectionist person who can tolerate high levels of pain and is very compliant and easy to coach.

"Some of those characteristics might make you say, a very good long-distance runner, and they overlap a little bit with some of the psychological traits that might help you towards an anorexic life."

The competitive nature of athletes is also thought to be a risk, with the concept of "competitive thinness" arising among groups of athletes, Currie said.

"Athletes are competitive by nature and they will compete on anything," he said. "People who have been at a Games village, for example, will talk about a card game after the competition is over, which is probably the most intensely competitive card game you have ever seen.

"Sometimes they get attracted towards trying to be thinner and thinner. You want to be faster or stronger than everyone on the team, but you want to be leaner as well. For some vulnerable people that is an additional risk factor."

But he added: "For any given individual, there is not one cause. When you start unpicking their story, you usually pick up a degree of vulnerability that might go way beyond even their involvement in sport. Then it is something about the environment that they found themselves in which added a few additional risk factors."

A spokesman for UK Sport said the working group on eating disorders was in the early stages and has met once so far.

He said: "The aim is to go out to a number of sports over the next few months directly to look at what is happening on the ground, and then work out what support mechanisms can be put in place across the sports industry, whether sport-specific, or more generically."