<qa>  What is the effect of a parallel change in heart rate?4. Non-Invasive methods to measure the role of ANS Some authors suggest that the altered autonomic control of the caliber of airway in asthma can be reflected through a parallel change in heart rate HR, as it is shown that in the asthmatic population are more likely to elevated resting heart rate compared to asthmatic population. Asthma and allergy has been associated with an increased activity of the PNS and asthma causes an elevation of heart rate variability HRV, based on the measurement of basal parasympathetic tone. In fact, the authors asthma severity associated with greater impairment of HRV. 