Painkillers in sport: a form of legal doping or an excessive reliance on medication that puts the long-term health of athletes in jeopardy? With evidence of widespread use of over the counter anti-inflammatories to support performance or recovery at amateur level, File on 4 looks asks if there is enough regulation of painkilling drugs in sport across the ranks. About half of players competing at the past three World Cups routinely took non-steroidal anti-inflammatory drugs like ibuprofen, according to research carried out by FIFA's former chief medical officer, Prof Jiri Dvorak. For him, this clearly constitutes the abuse of drugs in football, one which risks player's health and could "potentially" have life-threatening implications. But is the sports community taking these warnings seriously enough? Professor Dvorak first warned about the long-term implications of players misusing painkillers in 2012 - has anything changed? Industry insiders their concerns about pain killer use in professional sport - including one former rugby international who says he developed serious long-term health problems as a result. And with evidence that even paracetamol can have a performance enhancing effect, how can sports regulators control substances that can give a competitive advantage but are widely available over the counter? With tales of athletes receiving pain relief in order to compete with broken toes or even a fractured bone in their back, we explore the lengths some may go to in order to stay in the game and ask if some sports are risking long-term harm by chasing short-term goals. Producer: Alys Harte Reporter: Beth McLeod.