Anti-inflammatories in endurance training
As a pharmacist by trade, obviously pharmacology and pharmacy in general are close to my heart. Added to that, I am a long-distance runner (self-professed) by choice and desire. Having run a few marathons and a couple of ultra-marathons now, I like to think I know a fair deal more than when I first started out. However, it would be naïve of me to imply that I know it all, or that there’s nothing more to learn. So when the opportunity came to write this article, I knew that I wanted to tick three boxes: It had to relate to pharmacology; it had to involve running; and we had to learn something from it.
Fortunately, I found a topic that will do just that. I’ve spoken about anti-inflammatory drugs before in my series of articles on doping in sports, so you already know that for the most part you can use them without getting banned or fined. So we’re allowed to use them, but…should you? My interest in this topic was first raised when I was chatting with another pharmacist about the nature of inflammation and anti-inflammatories. See, inflammation, as much as we may hate it, is a very necessary part of life. The pain, heat and redness we feel and see all serve a purpose. The process of inflammation is your body releasing chemical mediators that in turn attract important cells and other mediators, starting a whole cascade of events that, ultimately, results in healing. Healing is good, right? Especially when you’ve been training hard for that big race and you’ve been pushing yourself to the point of serious fatigue, healing is what you need to make sure that when it’s time to perform that you can do just that.
So then, do we really want to prevent inflammation? Is the use of anti-inflammatories counterproductive to post-training recovery? And we can extend the question further: do anti-inflammatory drugs negatively impact performance in endurance (running) events?
This would generally be a good time to start writing a research proposal and envisioning the big, impressive study you’re going to do to find out the answer to that question. Fortunately for me, somebody else has done all the hard work. Through a relatively casual search using the keywords ‘anti-inflammatory’, ‘running’, ‘endurance’ and ‘performance’, I managed to find a few articles to review.
Before I go into what I found, I want to make two things clear. First, the majority of articles found, and the focus of my search is non-steroidal anti-inflammatory drugs (NSAIDs). These are far more readily available than steroidal drugs like prednisone. One can easily acquire a five-day supply of NSAIDs from most community pharmacies. This class includes drugs such as ibuprofen, naproxen, indomethacin and diclofenac. Secondly, when I talk about these drugs, I am generally referring to the oral dosage forms, such as tablets and capsules. Many of these products are available as gels to be applied directly to an injured area. This limits the systemic absorption and limits side effects as a result. It also limits whole body effectiveness. For the purpose of this article, I am referring to oral dosage forms.
A study by Gorski et al. (2011) explored the prevalence of NSAID use in triathletes, specifically at an Ironman competition. Of 327 participants, 93 used an NSAID during the race, the majority of these participants stating that they used the medications for pain prevention. When asked about their knowledge on the effects of the NSAIDs, most athletes were aware of the anti-inflammatory and analgesic effects, but were unaware of most of the negative effects of the drugs. This is a cause for concern, particularly in endurance sports where dehydration is a risk. NSAIDs are often associated with gastrointestinal complications (stomach cramps and risk of peptic ulcers), but they have also been linked to risk of kidney damage and cardiac complications. In an environment where dehydration (another cause of kidney damage) is common, and the cardiovascular system is under persistent pressure, the lack of education on these products could have serious ramifications.
So, health risks are one thing, but people have been known to throw caution to the wind with regards to their health, particularly when there is a goal to be pursued. But when it comes to goals, performance is everything. On that point, a 2010 study by Machida and Takemasa (2010) explored the effect of ibuprofen in mice with regards to skeletal muscle adaptations. While a study on mice is obviously difficult to correlate to humans, it is interesting to note that while the mice that were administered ibuprofen did manage to run longer distances than mice without, the running-distance-dependent adaptations one expects to see with endurance training did not occur. These adaptations typically include an increased capillary-to-fibre ratio and increases in IIa myofibre. This study therefore suggests that even if ibuprofen allowed the participant mice to run further, the benefit typically associated with running longer distances was not present. So, in essence, the positive effects of endurance training could be suppressed by NSAID use.
Returning to studies on humans, Da Silva et al. (2015) conducted a randomised controlled clinical trial in male long-distance runners, comparing a cohort supplied with ibuprofen versus a cohort supplied with placebo. Following a muscle injuring protocol, the results revealed that ibuprofen had no positive preserving effect on muscular endurance. Overall there was no ergogenic effect associated with ibuprofen.
At this point, three things have become abundantly clear to me: 1) NSAIDs are not necessarily associated with better performance in endurance events; 2) NSAIDs are associated with adverse effects that could be actively harmful to endurance athletes; 3) this is a topic needing and deserving of further study.
This article is just a brief insight into a topic that is of relevance to anyone participating or wishing to participate in endurance events. If you are an endurance athlete, I urge you to do further research yourself, and above all else to be mindful that just because you can get a medication over the counter at a pharmacy does not mean it’ll always be good for you. The negative effects of a drug can often far outweigh the positives. For myself, I think I’ll lay off the anti-inflammatories in my next injury. The body needs time to heal, and athletes (current or aspiring) owe it to themselves to listen. The body knows best.
Gorski, Tatiane, et al. "Use of NSAIDs in triathletes: prevalence, level of awareness and reasons for use." British journal of sports medicine 45.2 (2011): 85-90.
Da Silva E, Pinto RS, Cadore EL, Kruel LF. Nonsteroidal anti-inflammatory drug use and endurance during running in male long-distance runners. J Athl Train. 2015;50(3):295-302.
M. Machida, T. Takemasa Ibuprofen administration during endurance training cancels running-distance-dependent adaptations of skeletal muscle in mice. J Physiol Pharmacol. 2010 Oct; 61(5): 559–563.