Caffeine may ease post-workout muscle pain

By Amy Norton

NEW YORK (Reuters Health) - That morning cup of coffee may be an antidote to post-exercise muscle soreness, if preliminary research is correct.

In a small study of female college students, researchers found that a caffeine supplement seemed to lessen the familiar muscle pain that crops up the day after a particularly challenging workout.

Known as delayed-onset muscle soreness, or DOMS, the pain is common in the day or two after a workout that was more intense than normal. Exercise that involves eccentric contraction of the muscles is particularly likely to cause delayed muscle pain.

In eccentric contraction, the muscle produces a force while it's being lengthened. This happens when a person runs downhill, for example, or lowers a weight during a bicep curl.

Exercisers and researchers alike have tried many ways to prevent DOMS -- including over-the-counter painkillers, stretching and massage -- but studies have found no cure-all for the problem.

In the current study, published in the Journal of Pain, researchers at the University of Georgia in Athens looked at the effects of a caffeine supplement on delayed muscle pain in nine young women.

First, in a simulated workout, the researchers used electrical stimulation to produce eccentric contractions in the women's thigh muscles -- enough to cause moderate day-after soreness.

Next, they repeated the procedure over the next two days, but on each day, the women took either a caffeine pill or placebo pill one hour before the muscle workout. Neither the women nor the researchers knew which pill was given on which day.