Effect of respiratory muscle training on pulmonary function in preoperative preparation of tobacco smokers1 Efeito do treinamento dos músculos respiratórios sobre a função pulmonar no preparo pré-operatório de tabagistas

Purpose: To evaluate the effect of utilization of a specific training program of respiratory muscles on pulmonary function in tobacco smokers. Methods: Fifty asymptomatic tobacco smokers with age superior to 30 years were studied, at the moments: A0 initial evaluation followed by protocol of respiratory exercises; A1 reevaluation after 10 minutes of protocol application; and A2 final reevaluation after 2 weeks of training utilizing the same protocol 3 times per week. The evaluation was realized through measures of maximum respiratory pressures (PImax and PEmax), respiratory peak flow (IPF and EPF), maximum voluntary ventilation (MVV), forced vital capacity (FVC) and forced expiratory volume at the 1st second (FEV1). Results: There was no improvement from initial to final evaluation in FVC and FEV1. But there were significant increases in the variables IPF, EPF, MVV and PImax at evaluations A1 and A2. The PEmax variable increased only at evaluation A2. Conclusion: The application of the protocol of respiratory exercises with and without additional load in tobacco smokers produced immediate improvement in the performance of respiratory muscles, but this gain was more accentuated after 2 weeks of exercise.