| Popis: |
Pseudoephedrine is an over-the-counter drug commonly used as a decongestant, but also thought to have ergogenic effects. The World Anti-Doping Agency (WADA) has prohibited large doses (> 150 μg∙ml-1) of pseudoephedrine, while the National College Athletic Association (NCAA) does not include it on the banned substance list. The purpose of this study was to examine the effect of body weight dosing of pseudoephedrine on 800-m run times of NCAA female runners. Fifteen NCAA female track runners volunteered to participate in the randomized, double blind, crossover design. In trials that were a week apart, participants were given both 2.5 mg∙kg-1 pseudoephedrine and a placebo. Ninety minutes post-ingestion, participants completed an 800-m individual time trial on an indoor track. Finishing time was recorded with an automated video timing device. Heart rate and anxiety state scores were recorded immediately after each trial. Finally, a urine sample was taken from 5 participants about 2 hr post-ingestion. Placebo and pseudoephedrine running times were compared using a iv paired t test. Heart rate and anxiety state scores were also compared using a paired t test. Fourteen runners completed both trials and one was an outlier, giving thirteen participants used for statistical analysis. Despite being dosed (144 mg ± 17 mg) well above normal therapeutic levels, there was no significant difference (p = 0.92) in 800-m times between the placebo (2:39.4 ± 9.6) and pseudoephedrine (2:39.4 ± 9.6) trials, in post-exercise heart rate (p = 0.635, pseudoephedrine = 177.9 ± 14.5 beats∙min-1, placebo = 178.4 ± 18.5 beats∙min-1), or in anxiety state levels (p = 0.650, pseudoephedrine = 38.4 ± 11.6, placebo = 38.1 ± 8.8). A 2.5 mg∙kg-1 dose of pseudoephedrine had no effect on 800-m run times in NCAA female runners, and did not raise urine levels above 150 μg∙ml-1. This raises the question as to why pseudoephedrine is a specified prohibited substance by WADA. (49 pages) |
