Painkillers in sport: A 'career necessity' or a 'serious health risk'?
Listen to 'Gain Without the Pain - Legal Drugs in Sport': File on Four, on BBC Radio 4, Tuesday 30 May, at 20:00 BST.
"Painkillers were my friend, my close lover at times, and at one point in my athletics career, they were just necessary."
Like many retired elite sportmen and women, former Great Britain decathlon Olympian Daniel Awde has spoken openly about a heavy reliance on painkillers.
But this is not just an issue at the top of sport - it affects amateur athletes too.
A poll for BBC's State of Sport week found that 60% of amateur athletes took over-the-counter anti-inflammatories like ibuprofen and naproxen to support their performance or recovery at least once a week.
Building on that research, File on Four spoke to a range of experts and sporting figures to ask whether the use of painkillers in sport has reached epidemic proportions.
The path to addiction
Former England rugby league captain Danny Sculthorpe
"They reckon every tackle in a rugby league match is like a 30mph car crash. So if you're in 50 car crashes on a Sunday, your body's going to be in bits for quite a number of days.
"I used to get up in the morning after and take some paracetamol, taking naproxen, just get some anti-inflammatories in you.
"A lot of them were pink and looked like Smarties so that's what they used to call them."
Sculthorpe said players would regularly take stronger painkillers like tramadol and after major surgery on a spinal injury, he began taking fentanyl, one of the strongest painkillers available.
"I was on these massive amounts for so long, I did get addicted to them," Sculthorpe said.
"A lot of players have been addicted to stuff, it just goes to show players aren't immune - in fact they're probably more likely to get addicted because they take them a lot more than other people".
Sporting Chance - a charity that helps athletes with issues including addiction - told the BBC that around 80 current and retired rugby league players have used their services every year since 2013 and a sizeable number of those are seeking help with painkiller addiction.
The health risks
Dr Ajai Seth, Sports and Exercise Clinic, Queen Elizabeth Hospital, Birmingham
"If someone was over-training and relying on anti-inflammatories to a higher degree, you would have much more serious effects on bone healing, potential fractures, some not healing at all.
"And if that was to happen, it may end someone's running career completely, it may even affect their quality of life massively.
"You can go from being a high-level athlete to being completely incapacitated by an injury in a relatively short period of time if you rely on anti-inflammatories."
On longer term health effects, Dr Seth added: "That's something that can happen over years and decades, but there is increased risk of cardiac health issues, kidney failure, and worsening respiratory conditions."
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How widespread is painkiller use?
Former England rugby captain and Leicester and Bath flanker Lewis Moody
"In a sport like rugby you never play 100% fit. I remember being on a bus and it was a competition to see how many [anti-inflammatories] you could take, which is ridiculous.
"We were advised there was always a certain limit on the number that you could take but when you play a game for long enough, your access to pills and drugs all the time is vast. So boys can build up quite a supply if they want to."
Moody developed ulcerative colitis - where ulcers develop in the bowel - during his career and believes his use of painkillers contributed to that.
Awde, who retired in 2012, openly admits to having used a cocktail of painkillers during this career.
"Within the athletics community I think it was a running joke that a lot of athletes were having ibuprofen for breakfast, lunch and dinner," he told the BBC. "You know everyone seemed to have it everywhere. It became sort of part and parcel of it all.
Awde recalls taking "about 13 or 14" tablets in a day while competing with a knee injury and attempting to qualify for the London 2012 Olympic Games.
"I didn't think of the consequences…if there were any consequences."
What can be done?
Professor Nicola Maffulli, a top sports injury specialist
Professor Maffulli told File on Four that while clubs might see a player as an "asset", a doctor's duty of care is to protect the patient - but that in practice this is not always the case.
"Obviously things have changed and now with the emphasis on sport as a way of showing off how good one is, or how good a nation is - sport has become for winning.
"Unfortunately, this winning ethos can translate in the adoption of practices which are at times less than ethical.
"Let's say that you're a top athlete, that you've been training for eight years to go to the Olympics and you only have this last hurdle before a gold medal, which will change your life, and you're only asked to perform for 30 seconds. What would you do?"
Moody says athletes will always take legal painkillers to try to play through pain and that medical staff should take "the responsibility away from the player".
What the authorities said
The Rugby Football League told File on Four it has a "strong record" of supporting current and former players and an education programme on the risks "associated with prescription painkillers".
World Rugby, which governs rugby union, said: "Player welfare is the number one priority and we operate an evidence-based approach to injury education, prevention and management."
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