title: Combined inhalation of beta2 -agonists improves swim ergometer sprint performance but not high-intensity swim performance.
abstract: There is a high prevalence of asthma and airway hyperresponsiveness (AHR) in elite athletes, which leads to a major use of beta2 -agonists. In a randomized double-blinded crossover study, we investigated the effects of combined inhalation of beta2 -agonists (salbutamol, formoterol, and salmeterol), in permitted doses within the World Anti-Doping Agency 2013 prohibited list, in elite swimmers with (AHR, n = 13) or without (non-AHR, n = 17) AHR. Maximal voluntary isometric contraction of m. quadriceps (MVC), sprint performance on a swim ergometer and performance in an exhaustive swim test at 110% of VO2max were determined. Venous plasma interleukin-6 (IL-6) and interleukin-8 (IL-8) were measured post-exercise. No improvement was observed in the exhaustive swim test, but swim ergometer sprint time was improved (P < 0.05) in both groups from 57 ± 1.7 to 56 ± 1.8 s in AHR and 58.3 ± 1 to 57.4 ± 1 s in non-AHR. MVC and post-exercise plasma IL-6 increased (P < 0.05) with beta2 -agonists in both groups, whereas IL-8 only increased in AHR. In summary, inhalation of beta2 -agonists, in permitted doses, did not improve swim performance in elite swimmers. However, swim ergometer sprint performance and MVC were increased, which should be considered when making future anti-doping regulations.
authors.affiliation: Respiratory Research Unit, Bispebjerg University Hospital, Copenhagen, Denmark; Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark.
authors.forename: A
authors.initials: A
authors.lastname: Kalsen
authors.forename: M
authors.initials: M
authors.lastname: Hostrup
authors.forename: J
authors.initials: J
authors.lastname: Bangsbo
authors.forename: V
authors.initials: V
authors.lastname: Backer
mesh_terms: D000280:Administration, Inhalation; D000293:Adolescent; D058666:Adrenergic beta-2 Receptor Agonists / Q000494:pharmacology*; D000420:Albuterol / Q000031:analogs & derivatives / Q000494:pharmacology; D054874:Athletic Performance / Q000502:physiology*; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004983:Ethanolamines / Q000494:pharmacology; D005260:Female; D000068759:Formoterol Fumarate; D006801:Humans; D015850:Interleukin-6 / Q000097:blood; D016209:Interleukin-8 / Q000097:blood; D007537:Isometric Contraction / Q000187:drug effects; D008297:Male; D053580:Muscle Strength / Q000187:drug effects*; D010807:Physical Endurance / Q000187:drug effects*; D052097:Quadriceps Muscle / Q000502:physiology; D000068299:Salmeterol Xinafoate; D013550:Swimming / Q000502:physiology*
chemical_list: D058666:Adrenergic beta-2 Receptor Agonists; D004983:Ethanolamines; D015850:Interleukin-6; D016209:Interleukin-8; D000068299:Salmeterol Xinafoate; D000420:Albuterol; D000068759:Formoterol Fumarate
keywords: airway hyperresponsiveness; competitive swimmers; doping; plasma interleukins; quadriceps muscle strength; sprint performance