"This experiment found that caffeine (equal to about two cups of brewed coffee) could produce a large reduction in pain resulting from eccentric exercise-induced, delayed-onset muscle injury," wrote lead author Victor Maridakis from the University of Georgia.
"This finding may improve the quality of life of individuals who experience skeletal muscle pain after engaging in unaccustomed, eccentrically biased exercise."
But the researchers warned that the study, which only involved nine women with low caffeine intake, may not be applicable to the more general population, particularly regular caffeine users.
The average worldwide daily coffee consumption of one and a half cups, while the US average is more than three and a half cups.
Writing in the Journal of Pain, the Georgia researchers report the results of their experiment with nine university-age women with regular low caffeine consumption. The volunteers were assigned to receive either caffeine or placebo 24 and 48 hours after exercise session that caused moderate muscle soreness in their thigh muscles (quadriceps).
The volunteers than performed two different quadriceps exercises, one designed to produce a maximal force, the other designed to generate a sub-maximal force. The researchers report that the women who consumed caffeine one-hour before the maximum force test had a 48 per cent reduction in pain compared to the placebo group, while those that took caffeine before the sub-maximal test reported a 26 per cent reduction in pain.
"This experiment found that caffeine (equal to about two cups of brewed coffee) could produce a large reduction in pain resulting from eccentric exercise-induced, delayed-onset muscle injury," wrote the researchers.
Maridakis said in a statement that the findings may be particularly relevant to people new to exercise, since they tend to experience the most 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," he said.
Co-researcher Patrick O'Connor said that caffeine might even be more effective in relieving post-workout muscle pain than several commonly used drugs. O'Connor said that previous studies have reported that the pain reliever naproxen produced a 30 per cent reduction in soreness, while aspirin produced a 25 per cent reduction, and ibuprofen has produced inconsistent results.
"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," he said.
The Georgia-based researchers added that people should use caution when using caffeine before a workout since too much caffeine can produce side effects in some people.
"It can reduce pain," Maridakis said, "but you have to apply some common sense and not go overboard."
Zoë Wheeldon, spokesperson for the British Coffee Association (BCA) told NutraIngredients.com that all new research was interesting but that the BCA would like to see more studies before it is known if the results of this small sample can be applicable to the wider population.
Wheeldon said that the other studies have shown that having coffee before exercise may help us to exercise for longer and harder, and that the drink is actually recognised as an important source of fluid in the diet.
She also noted that the drink is a rich source of antioxidants, improves performance and alertness, and may be used to assist sports training.
Source: The Journal of Pain Published on-line ahead of print; doi:10.1016/j.jpain.2006.08.006 "Caffeine Attenuates Delayed-Onset Muscle Pain and Force Loss Following Eccentric Exercise" Authors: V. Maridakis, P.J. O'Connor, G.A. Dudley, K.K. McCully