Proper mucociliary clearance depends on the amount of
mucus, its rheological properties, intact ciliary structure
and activity, and the perfect interaction among these components. Neurohormones and neurotransmitters associated
with the autonomic nervous system also exert a significant
influence on mucociliary clearance because cholinergic
and adrenergic agents stimulate the mucociliary activity or
ciliary beat frequency.41,58 Thus, the association between
mucociliary clearance and the autonomic nervous system
was also investigated in this study with heart rate variability indexes, and significant correlations were found in both
groups when submitted to aerobic exercise.