Drinking coffee could help reduce the post-workout pain that puts many people off exercise, a small study suggests.
Moderate amounts of coffee could help reduce post-exercise soreness
The study found moderate doses of caffeine, roughly equivalent to two cups of coffee, can cut muscle pain by up to 48%.
But researchers at the University of Georgia warned their findings may not be applicable to regular caffeine users who are less sensitive to its effects.
The report was published in The Journal of Pain.
The researchers studied nine female college students who were not regular caffeine users and did not engage in regular strength-building training.
One or two days after an exercise session that caused moderate muscle soreness, the volunteers took either caffeine or a placebo and performed thigh exercises.
Volunteers that consumed caffeine had a 48% reduction in pain compared to the placebo group when performing maximum force thigh exercise, and a 26% reduction in sub-maximal force exercises.
Lead author Victor Maridakis said: "If you can use caffeine to reduce pain, it may make it easier to transition from that first week into a much longer exercise program."
Professor Patrick O'Connor who co-authored the study said caffeine may work to reduce pain by blocking the body's receptors for adenosine, a chemical released in response to inflammation.
Caffeine may alleviate pain by blocking adenosine receptors
The researchers warned there were limitations to their findings though.
For example, the small size of the study means it will need to be replicated on a larger scale, and the findings may not be applicable to regular coffee users, or to men.
The researchers recommended that people are cautious about using caffeine before a workout, as too much caffeine can cause side-effects such as jitteriness and sleep disturbance.
Mr Maridakis said: "It can reduce pain, but you have to apply some common sense and not go overboard."
Greg Whyte, a physiologist at the British Association of Sport and Exercise Science, said the soreness felt after exercise is normal and actually a sign that muscles are responding to the exercise.
He said if caffeine is merely reducing the symptoms but not the underlying causes of the pain then it could be useful, but as it can have a diuretic effect it "may cause other problems" after exercise when rehydration is important.
He added that the muscle soreness could also be helped by methods such as stretching, ice-bathing or massage.
Zoë Wheeldon, spokesperson for the British Coffee Association said coffee has been shown in many studies to increase drinkers' capacity to exercise harder and for longer.
But on the new research she said: "This is very interesting, but we should not get too excited just yet and we would like to see more research."
She said the small size of the study in particular meant the results should not yet be extrapolated, for instance to regular coffee users.
However she added that there were many health benefits to drinking moderate amounts of coffee, as it is a source of antioxidants, improves alertness and performance, and can be used to aid sports training.