I've written previously about the risks of endurance athletes using ibuprofen and other NSAIDs prior to training and competition, but it's back in the news. Another research study adds to the growing evidence that taking ibuprofen or other anti-inflammatory painkillers before exercise doesn't offer any benefit, and it may actually cause physical damage, particularly to the intestines.
When we exercise the blood flows to where it's needed—the working muscles—and digestion slows way down. This is one reason you may experience cramps if you eat a lot prior to intense exercise. However, this the new research shows that without blood flow, some of the cells lining the small intestines are damaged and start to leak, and those study subjects who took ibuprofen prior to exercise showed evidence of even more leakage.
While the researchers aren't stating specifically all the long-term consequences of ibuprofen use, the concern is that intestinal integrity may be compromised and would allow small amounts of bacteria and digestive enzymes to leak into the bloodstream. Other concerns include a possible decrease in the ability to absorb nutrients, especially after exercise, which is the best time for athletes to replenish glycogen stores.
Read more about these and other studies of ibuprofen use and athletes in the New York Times blog, Well.