Autonomic changes in young smokers: acute effects of inspiratory exercise

Abstract

One of the most important consequences of smoking is the development of cardiovascular diseases. However, little is known about the early consequences of smoking and the acute effects of a single inspiratory muscle exercise session (IME). We evaluated the acute effects of an IME on cardiac parameters of young smokers. Twelve nonsmokers (C) and fifteen smokers [S; 2.08 (1.0-3.2) pack-years] underwent an acute IME. We evaluated blood pressure (BP) and lactate, and we recorded RR interval for posterior analysis of heart rate variability (HRV), before and after IME. At baseline, systolic BP and HRV parameters in time and frequency domains were changed in S group in comparison with the C. Following IME, S group reduced systolic BP (-8 %), low frequency band (LF) (-21.4 %), LF/high frequency (HF) (-57 %), as well as increased RR variance (+105 %) and HF band. Our findings indicate that a single session of inspiratory muscle exercise was able to both reduce systolic BP and improve parasympathetic and sympathetic modulations in young smokers. The results of the current study highlight the importance of furthering research on this area to better elucidate the acute and chronic effects of inspiratory muscle training on early cardiovascular and pulmonary changes of cigarette smoking.