SEATTLE, June 1 (UPI) -- Ingesting caffeine within an hour of exercise can reduce the symptoms of exercise-induced asthma, U.S. researchers said.
Co-investigator Timothy Mickleborough of Indiana University in Bloomington and colleagues said the caffeine study involved 10 subjects with exercise-induced asthma in a randomized, double-blind, double-dummy, crossover study.
The subjects ingested 3, 6 or 9 milligrams of caffeine per kilogram of body weight or a placebo an hour before running on a treadmill. Pulmonary function tests were conducted 15 minutes before a eucapnic voluntary hyperpnea challenge -- a surrogate for an exercise challenge -- and then again one, five, 10, 15 and 30 minutes afterward.
The researchers found 9 milligrams of caffeine per kilogram of body weight was as effective as the use of an albuterol inhaler to treat or prevent exercise-induced asthma. The smaller amounts of caffeine of caffeine per kilogram of body weight also reduced the wheezing, coughing and other symptoms of exercise-induced asthma.
For someone weighing 150 pounds, 3 to 9 milligrams of caffeine per kilogram of body weight equals around 205 to 610 milligrams of caffeine, Mickleborough said.
The findings were presented at the American College of Sports Medicine conference in Seattle.