Eleven hours, 21 minutes and 15 seconds — that's how long it took Flora Colledge from jumping into the Hardangerfjord in Norway to celebrating at the top of the 1,883 meter Gaustatoppen mountain. "It was a dream come true," the 37-year-old Briton said of her Norseman triathlon victory this year. "It was my fifth attempt to win this event."

After two second-place finishes in 2019 and 2021, Colledge finally reached the top of the podium and can now call herself a XTri world champion. XTri stands for extreme triathlon and along with the distance of an Ironman race — 3.8km swim, 180 km cycle and a 42.4km run — is the extra challenge of the course. In the Norseman, around 3,000 metres of altitude have to be overcome on the bike and it's more than 1800 metres in the marathon.

Flora Colledge is not just an extreme athlete though, but also a sports scientist who is currently researching the phenomenon of sports addiction, specifically looking at the ideas of compulsiveness, excessive sporting activity and a behavioural addiction.

Addiction risk from seven hours a week onwards

"I didn't start looking at it because I had the feeling that I would be at risk myself. The topic chose me," Colledge tells DW and laughs. "As an athlete at a high level, I find it exciting to explore the differences between sports addiction as a disorder and training with a high workload in a healthy way."

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Colledge herself trains around 25 hours a week. In her research, she has identified a mark of around seven hours a week as the threshold for a possible sports addiction.

"For someone who has a full-time job, a family and other commitments, one hour a day is not a small amount. If they still do sport and neglect other commitments to do so, you can talk about sports addiction from around seven hours of training per week," explains the scientist, who works at the University of Lucerne in Switzerland.

The phenomenon of sports addiction was discovered in passing in 1970. The New York doctor Frederick Baekeland wanted to investigate whether a lot of exercise promoted deep sleep. To this end, he offered money to passionate runners who trained daily. In return, they were to give up their sport for a month. Most of them refused, even when the scientist offered them large sums of money. Baekeland coined the term "exercise addiction". There are now more than 1,000 scientific articles on the phenomenon, and research has really taken off in the last five years.

In contrast to gambling and betting addiction, sports addiction is not yet recognised as an independent psychiatric disorder. Colledge admits that some studies should be treated with caution, stating that some forms of measurement used to identify sports addiction are "far too simple".

In a frequently used questionnaire, athletes are asked whether they have increased their training workload and whether they use sport to improve their mood. These are two of six questions. "An athlete will clearly answer yes to both questions," explains Colledge. "Of course you increase your training workload. And it's no problem at all that physical activity leads to a good mood. That's why we recommend sport."

Symptoms of anxiety and depression

But when does passion start to become addiction?

"Sport can play a central role in life, but it shouldn't be the only priority," says Colledge. People who are committed to sport have clear goals but, unlike addicts, can also cope well with breaks from training.

"Taking a day off is fine and does not lead to withdrawal symptoms. Sports addicts, on the other hand, report severe anxiety and severe depressive symptoms and even suicidal thoughts if they are unable to exercise regularly," says Colledge. This inner compulsion to exercise at all costs and never to reduce the intensity is one of the main warning signals.

That's why amateur athletes are potentially at even more risk.

"Professional athletes generally understand that you don't just get fitter through training, but that you also need recovery phases to compensate for the intensive training phases," says Colledge, who has a professional triathlon licence herself. "Sports addicts don't understand this. It's not about getting better, faster or fitter, it's just about completing a daily training programme. And that shouldn't be less tomorrow than it is today, maybe even a bit more."

Training despite fracture or fever

Opinions differ among scientists as to how many active people are addicted to sport. Endurance sports are considered to be particularly at risk. In 2022, for example, researchers identified a high risk of sports addiction among cyclists at six per cent. The risk among marathon runners was just under seven per cent.

However, a high risk does not necessarily mean a pathological disorder. An estimate by Simone Breuer and Jens Kleinert from the German Sports University of Cologne is often quoted in this context. According to this estimate, around one in a hundred athletes exhibits isolated abnormalities, one in a thousand tangible signs of a disorder. And one in ten thousand is probably in need of treatment. This also applies, for example, when symptoms of an eating disorder coincide with those of a sports addiction.

"It becomes pathological when sport has become a psychological burden," says Flora Colledge, citing the following example to highlight the point at which people should seek treatment. "I don't actually have time for two hours of training today because I have to work or look after my family. But I do it anyway, even between two and four in the morning if necessary, because there's no other way."

People who simply ignore illnesses or injuries and continue to train are also in need of treatment, says the sports scientist. "There are sports addicts who carry on despite a fatigue fracture or high fever. They are no longer able to listen to their body."

Searching for the right therapy

How do you treat a behavioural addiction that is not yet officially recognised as a psychiatric disorder?

"We are still at such an early stage of research that we haven't even been able to test forms of therapy," replies Colledge. "There is no clinical trial for sports addiction therapy."

However, there is evidence that so-called cognitive behavioural therapy (CBT) can be helpful. "You learn to deal with your feelings about sport in a different way. You try to slowly reduce the workload in order to come to terms with the feelings associated with it." Complete withdrawal from sport, as in the case of alcohol addiction, makes no sense: "People need sport, so complete abstinence is not an option."

Colledge says she will continue to take part in extreme triathlons.

"I'm more made for endurance sports. The longer, the better," says Colledge, who adds she just enjoys competing in impressive natural surroundings and in a small field. "It's less of a battle against other opponents. I really try to get the best out of myself in these challenging conditions. I think that's great." And without any addiction of course.