Article Text
Abstract
Objective: To study the effects of an acute therapeutic oral intake of β2 agonist on performance and substrate response during supramaximal exercise in women.
Methods: 12 healthy moderately trained female volunteers performed a Wingate test after ingestion of placebo (Pla) and salbutamol (Sal; 4 mg) according to a double-blind randomised crossover study. Blood samples were collected at rest, at the end of exercise and after 5 (r5), 10 (r10) and 15 (r15) min of passive recovery for adrenocorticotropic hormone (ACTH), growth hormone (GH), insulin, blood glucose and lactate measurements.
Results: Peak power (PP) and mean power (MP) significantly increased whereas time to peak power was significantly shorter with Sal than with Pla (p<0.05). No change was observed in the fatigue index. ACTH was not significantly modified but r15 growth hormone significantly decreased (p<0.05) after the intake of Sal. Both blood INS and blood glucose were significantly increased by the intake of Sal during all the experiments (p<0.01). Blood lactate was significantly increased by the intake of Sal compared with that of Pla (p<0.05) after 10 and 15 min of passive recovery.
Conclusion: From these data, acute therapeutic oral intake of Sal seems to induce, irrespective of the subjects’ gender, an improvement in performance during a supramaximal exercise—that is, increase in PP and MP. Further studies are necessary to clarify whether the mechanisms involved in the response to intake of Sal are linked to central and/or peripheral pathways.
- ANOVA, analysis of variance
- ACTH, adrenocorticotropic hormone
- EIB, exercise-induced bronchoconstriction
- GH, growth hormone
- Glu, glucose
- Ins, insulin
- Lac, lactate
- MP, mean power
- OC, oral contraceptive
- Pla, placebo
- PP, peak power
- Sal, salbutamol
- TTPP, time to peak power