The same degree of caffeine-related pain reduction during exercise occurs both in people who normally consume a lot of caffeine and in those with little or no caffeine intake, according to a U.S. study.
It included 25 fit, college-age males who were divided into two groups -- those who had a caffeine intake of about 400 milligrams per day (equal to three or four cups of coffee) and those who normally consumed little or no caffeine, United Press International reported.
The participants did two high-intensity, 30-minute exercise sessions. They were told not to consume caffeine for 24 hours prior to the sessions. One hour before each session, the participants were given a pill. On one occasion, the pill contained a placebo, and the other time, it contained 5 milligrams of caffeine per kilogram of body weight, about the same as two to three cups of coffee.
"What's interesting is that we found that caffeine tolerance doesn't matter, we were perplexed at first," study author Robert Motl, a professor of kinesiology and community health at the University of Illinois, said in a news release, UPI reported.
"Then we looked at reviews of the literature relative to caffeine and tolerance effects across a variety of other stimuli. Sometimes you see them, sometimes you don't. That is, sometimes regular caffeine use is associated with a smaller response, whereas, other times, it's not," Motl said.
The study was published in the April issue of the International Journal of Sport Nutrition and Exercise Metabolism.