Researchers say that's more muscle pain relief than commonly found with pain relievers like aspirin.
"A lot of times what people use for muscle pain is aspirin or ibuprofen, but caffeine seems to work better than those drugs, at least among women whose daily caffeine consumption is low," researcher Patrick O'Connor, of the department of kinesiology at the University of Georgia, Athens, says in a news release.
But caffeine's pain-relieving perks may not apply to those who regularly drink coffee and other beverages containing caffeine. Instead, researchers say caffeine appears to work best in people who don't regularly consume caffeine or exercise.
Therefore, they say, the findings may be most help to people new to exercise -- who also tend to experience the most muscle soreness.
"If you can use caffeine to reduce the pain, it may make it easier to transition from that first week into a much longer exercise program," says researcher Victor Maridakis, of the University of Georgia, in the news release.
Caffeine's Pain-Relieving Perk
In this small study, researchers studied caffeine's effects on postworkout muscle soreness in nine female college students who were not regular caffeine users and did not regularly engage in resistance training. The results appear in The Journal of Pain.
The women received tablets containing either the equivalent of two cups of coffee or a placebo 24 and 48 hours after a resistance-training session designed to produce muscle soreness.
An hour after taking the pills, the women were asked to perform two different exercises using their sore quadricep (thigh) muscles. The results showed that one hour after taking caffeine, the women experienced up to 48% less muscle pain than the placebo group.
In comparison, O'Connor says previous studies of drugs containing naproxen (the active ingredient in Aleve) produced a 30% reduction in muscle soreness, and those using aspirin showed a 25% reduction.
Researchers say more study is needed to examine caffeine's effects on muscle pain.
They recommend that people use caution when using caffeine before a workout. Too much may produce side effects like jitteriness, heart palpitations, and sleep disturbances.
"It can reduce pain," says Maridakis, "but you have to apply some common sense and not go overboard."
SOURCES: Maridakis, V. The Journal of Pain, Dec 11, 2006 online edition, to appear in February 2007 print addition. News release, University of Georgia, Athens.
By Jennifer Warner
Reviewed by Louise Chang