The effects of ephedrine on the physiological and psychological responses to submaximal and maximal exercise in man.

The purpose of this study was to determine whether a single full therapeutic dose (24 mg) of ephedrine taken orally has any effect upon physical performance and fitness. Twenty-one healthy males, aged 19-30 years, were tested on three occasions within three weeks using a double-blind modified crossover design. The effects of ephedrine were determined by comparing the differences between drug and control conditions using paired t-tests. The test battery included measures of muscle strength, endurance and power, lung function, reaction time, hand-eye coordination, anaerobic capacity and speed, cardio-respiratory endurance, and responses to maximal and submaximal effort, including maximum oxygen intake, ratings of perceived exertion and speed of recovery from effort. Despite a slight stimulating effect on blood pressure and on exercise and recovery heart rates, 24 mg of ephedrine had no effect on any of the measures of physical work capacity. Ephedrine had no effect on lung function of healthy young men, but may have assisted the learning of certain simple psychomotor tasks.