Researchers recruited 20 members of the Brazilian military who claimed to be regular runners. They performed their test by giving some participants Ibuprofen and others a placebo, then had each individual perform rigorous exercise on a treadmill. This allowed researchers to draw conclusions about those taking Ibuprofen and those taking a placebo. After exhausting trials of exercise and running, it was discovered that those who took Ibuprofen before running reached exhaustion at a slightly higher rate than those who took the placebo. Researchers stated “these observations indicate that long-distance runners should take caution when using [nonsteroidal anti-inflammatory drugs such as ibuprofen] to improve muscle-endurance performance because the side effects...may outweigh the expected benefits.”