Abstract: Pseudoephedrine is an over-the-counter drug to relieve nasal and sinus congestion. Although it has been suggested that pseudoephedrine could be a stimulant and ergogenic aid, pseudoephedrine was recently removed from the banned substance list by the International Olympic Committee and placed on the monitoring program (from January 2004). It was felt that evidence was lacking for an ergogenic effect, although few studies have investigated the effects of pseudoephedrine on exercise performance. This study, therefore, aimed to investigate the effects of pseudoephedrine on 1500-m running performance.
Methods: In a double-blind, randomized crossover design, seven male athletes completed two 1500-m running trials on an outdoor track after having completed a familiarization trial. All trials were 7 d apart. After a 12-h overnight fast, subjects reported to the laboratory and received a standardized breakfast (energy ≍ 500 kcal 50% CHO). Subjects were given either 2.5 mg·kg−1 bw pseudoephedrine or 2.5 mg·kg−1 bw maltodextrins (placebo) in gelatin capsules 70 min before the start of the warm-up, which started 20 min before they ran 1500 m all-out. Pre- and postexercise blood samples were collected and analyzed for lactate and glucose concentrations, partial pressure of oxygen (PO2) and carbon dioxide (PCO2), and percent oxygen saturation.
Results: Pseudoephedrine significantly decreased time to completion of 1500-m time trials in the present study by 2.1% (from 279.65 ± 4.36 s with placebo to 273.86 ± 4.36 s with pseudoephedrine) with no reported side effects. No changes in the measured blood parameters were found, suggesting a central effect of pseudoephedrine rather than a metabolic effect.
Conclusion: The finding was that 2.5 mg·kg−1 bw pseudoephedrine ingested 90 min preexercise improves 1500-m running performance.
1School of Sport and Exercise Sciences, University of Birmingham, Edgbaston, Birmingham, UNITED KINGDOM; and 2English Institute of Sport, Birmingham, UNITED KINGDOM
Address for correspondence: Asker Jeukendrup, School of Sport and Exercise Sciences, University of Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom; E-mail: firstname.lastname@example.org.
Submitted for publication May 2005.
Accepted for publication August 2005.