NSAIDs are commonly used to minimise pain and the risk of injury as well as to treat existing injuries

Anti-inflammatory drugs, such as over-the-counter ibuprofen, are commonly used by runners to ease post-exercise aches, pains or injuries, but carry a risk of harm according to a new study into the use of the pain killers by recreational runners in the UK. 

Non-steroidal anti-inflammatories (NSAIDs) block the production of inflammatory chemicals called prostaglandins, which reduces pain and inflammation, however they also block protective prostaglandins in the stomach and prostaglandins that help maintain kidney function. Intended for short-term pain relief, the drugs have well documented established risks, including acute renal impairment and gastrointestinal problems.

The use of NSAIDs amongst athletes across all sports and levels is well known, with the drugs commonly used to minimise pain and the risk of injury as well as to treat existing injuries.  It is thought that the associated risks of NSAIDs are heightened when used by athletes during endurance events. The stress placed on the human body during an event such as a marathon, can put additional pressure on the renal and gastrointestinal system, increasing the risk of harms from NSAIDs.

Additionally, NSAIDs may increase the risk of conditions such as hyponatraemia - a potentially fatal reduction in sodium caused by water overload during endurance races. Additionally, they may also impair healing and the training adaptation to exercise. However, little is known about the use of the drugs amongst recreational sports people, for example runners regularly taking part in organised running events.

The research, led by a team at Queen Mary’s University London and the University of Birmingham, surveyed 806 Parkrun UK participants, over the age of 18. Participants had a mean age of 48 with a relatively even gender split (48% women and 52% men). The study used self-completed questionnaires, and looked at the use of both over-the counter NSAIDs such as ibuprofen, alongside prescribed medication such as diclofenac. Survey participants were asked about their history of sporting injury, use of NSAIDS before, during, and after exercise, reasons for taking NSAIDs, and adverse effects of NSAIDs.

  • Of the 806 participants, 88% had used NSAIDs in the past 12 months with just under 80% of the runners opting for ibuprofen
  • As might be expected, the study showed a significant association between the distance covered per week and injuries, with 70% of participants reporting a sporting injury within the last 12 months
  • The most common weekly distance reported by runners was between 11km and 20km (or 6.3–12.9 miles)
  • The use of NSAIDs before, during and after running varied with 57% of respondents having taken NSAIDs before a run or race, 11% during, and 67.7% afterwards
  • Women were more likely to use NSAIDs after a run or race (73%) than men (62%)

Importantly, 1/3 of those surveyed experienced a suspected adverse reaction to NSAIDs, including gastrointestinal discomfort, heart burn, nausea and vomiting, diarrhoea and gastrointestinal bleeding. While over half of respondents were aware of the risk of adverse gastrointestinal reactions, few were aware of the potential that NSAIDs may delay recovery time from exercise or an injury. Over 40% of runners did not know about the gastrointestinal, cardiovascular and renal side effects.

Co-author Dr Anthony Cox, from the University of Birmingham’s School of Pharmacy, said: “While our research has shown that injury is, as expected, associated with NSAID use, runners also reported using NSAIDs to facilitate participation in events, to push through injuries by increasing pain tolerance and to deal with post‐event soreness. Particularly concerning is the routine use of NSAIDs in marathon and ultra-marathon runners during race events, and high mileage training schedules.

“This high usage of NSAIDs, without full knowledge of adverse effect or cautions for use, is concerning. While prudent use of NSAIDs may be playing a valuable role in enabling individuals to participate in exercise they might otherwise avoid, we would recommend that organisers of longer endurance events should consider providing evidence‐based advice on the use of NSAIDs.”