Effects of pseudoephedrine on maximal cycling power and submaximal cycling efficiency.
OBJECTIVE
To study the effects of a therapeutic dose of pseudoephedrine on anaerobic cycling power and aerobic cycling efficiency.


METHODS
Eleven healthy moderately trained males (VO (2peak) 4.4 +/- 0.8 L x min(-1) participated in a double-blinded crossover design. Subjects underwent baseline (B) tests for anaerobic (Wingate test) and aerobic (VO (2peak) test) cycling power. Subjects ingested either 60 mg of pseudoephedrine hydrochloride (D) or a placebo (P) and, after 90 min of rest, a Wingate and a cycling efficiency test were performed. During the cycling efficiency test, heart rate (HR) and VO(2) were averaged for the last 5 min of a 10-min cycle at 40% and 60% of the peak power achieved during the VO (2peak) test.


RESULTS
There were no significant differences in peak power (B = 860 +/- 154, D = 926 +/- 124, P = 908 +/- 118 W), total work (B = 20 +/- 3, D = 21 +/- 3, P = 21 +/- 3 kJ), or fatigue index (B = 39 +/- 8, D = 45 +/- 5, P = 43 +/- 5%). There were no significant differences in HR at 40% power (D = 138 +/- 10, P = 137 +/- 10 beats.min-1) or 60% power (D = 161 +/- 11, P = 160 +/- 11 beats x min(-1). There were no significant differences in cycling efficiency at 40% power (D = 18.8 +/- 1.8, P = 18.5 +/- 1.8%) or 60% power (D = 20.3 +/- 2.0, P = 20.1 +/- 2.1%).


CONCLUSIONS
A therapeutic dose of pseudoephedrine hydrochloride does not affect anaerobic cycling performance or aerobic cycling efficiency.
Hodges
Alastair N H
AN
Allan McGavin Sports Medicine Centre and School of Human Kinetics, University of British Columbia, Vancouver, British Columbia, Canada.
Lynn
Brenna M
BM
Bula
Jonathan E
JE
Donaldson
Meghan G
MG
Dagenais
Marc O
MO
McKenzie
Donald C
DC
D000328:Adult; D001642:Bicycling / Q000502:physiology*; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004734:Energy Metabolism / Q000187:drug effects; D004809:Ephedrine / Q000008:administration & dosage*; D015444:Exercise / Q000502:physiology*; D006801:Humans; D008297:Male; D018482:Muscle, Skeletal / Q000187:drug effects*; D010101:Oxygen Consumption / Q000187:drug effects; D010807:Physical Endurance / Q000187:drug effects; D013647:Task Performance and Analysis
D004809:Ephedrine