Beta-2 agonists and exercise performance in humans

• Published in: Science & sports 2010-12, Vol.25 (6), p.281-290
• Main Authors: Collomp, K., Le Panse, B., Candau, R., Lecoq, A.-M., De Ceaurriz, J.
• Format: Article
• Language: English
• Subjects: Acute administration; Administration orale; Albuterol; Biological and medical sciences; Dopage; Doping; Fundamental and applied biological sciences. Psychology; Inhalation; Life Sciences; Oral intake; Prise aiguë; Prise de courte durée; Salbutamol; Short-term administration; Vertebrates: body movement. Posture. Locomotion. Flight. Swimming. Physical exercise. Rest. Sports
• ISSN: 0765-1597; 1778-4131
• DOI: 10.1016/j.scispo.2010.08.002

Due to fears of doping effects, the World Anti-Doping Agency has put certain restrictions on the use of the pharmacological class of beta-2 agonists. In 2010, all beta-agonists are prohibited except salbutamol and salmeterol by inhalation, which require a declaration of use in accordance with the international standard for therapeutic use exemptions. We reviewed the current literature to determine whether inhaled or oral beta-2 agonists enhance human performance and, based on our findings, we present hypotheses on the mechanisms that might account for the documented performance gains. Most of the trials were conducted after acute therapeutic inhalation and generally failed to show improved performance after such local low-dose administration, probably because of a lack of sufficient systemic bioavailability. In contrast, almost all trials after acute or short-term oral administration at therapeutic dosage demonstrated significantly improved performance, whatever the exercise intensity. The mechanisms by which the systemic administration of beta-2 agonists produces ergogenic effects are unknown, but the popular theory that salbutamol has an ergogenic effect due to its anabolic properties can be ruled out. The theory that it enhances substrate oxidation is incomplete, and both central and peripheral effects have been suggested. Further studies are needed with particular focus on: (1) the effects of systemic administration of terbutaline or bambuterol ; (2) the effects of short-term supratherapeutic inhalation, and (3) the determination of a urinary threshold for terbutaline, salmeterol and formoterol. En raison des possibles effets dopants, l’Agence mondiale antidopage a instauré certaines restrictions concernant l’utilisation des substances appartenant à la classe pharmacologique des bêta-2 agonistes. En 2010, tous les bêta-2 agonistes sont interdits, à l’exception du salbutamol et du salmétérol par inhalation, ces administrations locales nécessitant une déclaration d’usage. Nous proposons, à partir de la littérature scientifique actuelle, de faire un état des lieux des connaissances concernant les effets ergogéniques des bêta-2 agonistes. Parallèlement, certaines hypothèses à propos des mécanismes d’action potentiellement impliqués dans l’amélioration de performance sont présentées. La plupart des études ont été conduites suite à des inhalations de bêta-2 agonistes à dose thérapeutique et ne mettent pas en évidence d’amélioration de la performance sportive