It has been known for some time that caffeine has a positive effect on athletes that experience exercise-induced asthma (also known as exercise-induced bronchoconstriction). A recent study published by the International Journal of Sports Medicine, “Comparative Effects of Caffeine and Albuterol on the Bronchoconstrictor Response to Exercise in Asthmatic Athletes” found that moderate (6mg/kg) to high (9mg/kg) doses of caffeine provided a “significant protective effect against EIB”.
The study was conducted on ten asthmatic subjects. Though the sample size was relatively small, it was a randomized, double-blind, double-dummy crossover study. One hour pre-exercise, subjects were given 0, 3, 6, or 9mg/kg of caffeine or a placebo. Then, fifteen minutes pre-exercise subjects were given albuterol or a placebo. Scientists administered pulmonary function tests pre-and post-exercise to evaluate effectiveness of albuterol plus caffeine, albuterol plus caffeine placebo, caffeine plus albuterol placebo and placebo.
While caffeine only did provide some positive effects, caffeine did not seem to improve the affects of albuterol.
If you experience EIA/EIB, it might be worth reviewing the results of this study with your doctor. The study concluded that negative effects of daily use of short-acting beta2-agonists could be reduced by increasing caffeine consumption prior to exercise.
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