Anti-Inflammatories Decrease Workout Soreness
First of all, most NSAIDs (non-steroidal anti-inflammatories like Aleve, Motrin, and Advil) can reduce kidney function, and "if you're already dehydrated that can add additional stress to the kidneys," says Dr. Beckerman.
But Dr. Beckerman also doesn't like the idea of blocking your body's natural inflammatory response. Inflammation happens as a direct result of your body trying to repair damage done during your workout. If you block that process, you may not feel that unpleasant soreness, but you also may not reap as great a reward. Your body needs to be able to rebuild itself to get stronger.
There's more: One study found that NSAIDs taken before endurance distance events don't actually improve soreness after the event. And another showed that athletes who took an NSAID dose before working out had small levels of stomach bleeding after just one hour of cycling.
In fact, new research shows that anti-inflammatories actually cause more inflammation. In the gastrointestinal tract, NSAIDs damage the stomach and colon, making them porous and allowing seepage into the bloodstream and lymphatic system. That, in turn, triggers a body-wide inflammatory response.
A more sobering statistic to consider is that at least 100,000 Americans are hospitalized every year from NSAID-induced gastrointestinal bleeds with 16,500 resulting deaths, says Dr. Kerry Kuehl, director of the Human Performance Laboratory at Oregon Health and Science University.