Abstract
BACKGROUND: Mucociliary clearance is the main defense mechanism of the respiratory system, and it is influenced by several stimuli, including aerobic exercise and cigarette smoking. We evaluated the acute response of mucociliary clearance to aerobic exercise in smokers and nonsmokers compared with that found after acute smoking and smoking combined with exercise. Also, we investigated whether there was a correlation between mucociliary clearance and the autonomic nervous system under these conditions.
METHODS: Twenty-one smokers were evaluated for mucociliary clearance by saccharin transit time (STT), and the response of the autonomic nervous system was evaluated by heart rate variability after aerobic exercise, after exercise followed by smoking, after acute smoking, and after rest. For comparison, 17 nonsmokers were also assessed during exercise. Repeated-measures analysis of variance with the Tukey test or the Friedman test followed by the Dunn test was used to evaluate the STT, autonomic response, and other variables to exercise and/or smoking in smokers. A paired t test or Wilcoxon test was used to analyze responses to exercise in nonsmokers. Correlations were evaluated using Pearson or Spearman coefficients.
RESULTS: The STT was reduced after exercise in both groups, with similar responses between them. Other stimuli also reduced the STT. The STT showed a negative correlation with sympathetic activity in smokers and a positive correlation with the parasympathetic system in nonsmokers.
CONCLUSIONS: Although impaired in smokers, mucociliary clearance responded to the stimulus of exercise, as demonstrated by similar STTs compared with nonsmokers. This response was correlated with the autonomic nervous system in both groups. In smokers, mucociliary clearance also responded to the stimuli of smoking and exercise followed by smoking.
Footnotes
- Correspondence: Ercy MC Ramos PhD, Departamento de Fisioterapia, Universidade Estadual Paulista, Rua Roberto Simonsen, n° 305, Presidente Prudente, São Paulo, CEP 19060-900, Brazil. E-mail: ercy{at}bol.com.br, ercy{at}fct.unesp.br.
This study was supported by the Pró-Reitoria de Extensão Universitária (PROEX)/Universidade Estadual Paulista (UNESP), Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) grants 2012/09932-0 and 2012/04699-6, and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) grant 2012/484658. This study was registered in the Brazilian Clinical Trials Registry (CAAE: 04397312.8.0000.5402). The authors have disclosed no conflicts of interest.
- Copyright © 2015 by Daedalus Enterprises