Among some athletes, it’s known as “vitamin I,” but the painkiller ibuprofen is now suspected of doing more harm than good, at least when taken before a stressful athletic event. Writing in the New York Times, Gretchen Reynolds reports on research conducted at Maastricht University that put nine healthy men through some experimental paces during four visits. On two visits, the men rested for an hour, and before one visit, they took 400 milligrams of ibuprofen the night before and the morning of their visit. In the two other visits the men did the same thing, except instead of resting, they rode hard a stationary bike. When they were done, the researchers drew blood to see if the “normal” leakage of proteins from intestines after exertion was influenced by the ibuprofen. What did they find? The leakage was was much higher in the men who both took ibuprofen and rode hard than it was in men who took ibuprofen and didn’t ride, or in men who rode without ibuprofen. Reynolds reports that the protein levels remained elevated for several hours. Wait, there’s more: according to Reynolds, other studies have shown that there is no benefit from ibuprofen taken before an athletic event. Read more from Gretchen Reynolds.