Avoid pain killers and non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen during training because they damage the gut and hinder absorption of nutrients, delaying recovery. NSAIDs have also been shown to impair healing of tendons and blunt muscle hypertrophy response.
A recent study published in the journal Medicine and Science in Sports and Exercise tested what happens in the gastrointestinal tract during intense exercise after taking ibuprofen. Researchers measured a biomarker called IFABP, which when elevated, indicates damage to intestinal cells and is a marker of extended inflammation. IFABP was tested in trained cyclists at rest with ibuprofen, and after intense cycling with and without ibuprofen. A dose of 400 mg of ibuprofen was taken about 12 hours before exercise and another 400 mg was taken an hour before exercise.
Results showed significant damage to the cells in the intestines after exercise with ibuprofen. Markers of damage following the cycling trial with ibuprofen was almost double that following the cycling trial without the drug (875 vs. 474 pg/mL). In addition, following exercise with ibuprofen, other markers indicated that the barrier of the gut was injured, essentially causing leaky gut.
Researchers believe that when you combine intense physical activity with NSAIDs, damage to the intestines is increased as a result of redistribution of blood flow from the gut to the muscles, skin, heart, and lungs. This harms the lining of the gut, which could put you at risk for greater susceptibility to toxins because the gut lining is more permeable and not as protective. It will also inhibit absorption of nutrients, and long-term NSAID use could lead to serious damage to the gut and chronic inflammation.
There is other bad news about NSAID use with exercise: It has been associated with increased risk of cardiovascular adverse events and been shown to get in the way of long-term tendon and muscle repair. NSAIDs reduce the regeneration of satellite cells, which are the cells that rebuild connective tissue that joins muscle with bone.
NSAIDs also impair the muscle hypertrophy response by 50 to 75 percent in animals. In addition, we know they suppress protein synthesis following a single bout of exercise, possibly blunting muscle development in humans as well.