Effect of high-intensity exercise on aerobic performance and airway inflammation in asthma

Abstract

Background: Low levels of physical fitness are associated with an increased body mass index (BMI) and both are related to the occurrence of asthma. This association may be mediated by airway inflammation. Therefore, the aim was to quantify the effects of a three month high-intensity exercise intervention on aerobic performance and airway inflammation in children with asthma, as part of a wider randomised controlled trial. Methods: 125 participants with asthma (aged 13.0±1.1years, BMI 21.8±4.7kg·m -2 ; male n=68) were randomised to receive an extracurricular high-intensity exercise intervention (one school, n=42) or control (four schools, n=83). The intervention consisted of 30 minute sessions, three times per week for three months using a 1:1 ratio of exercise to rest personalised to >90% estimated heart rate max. Baseline and three month measures included stature, body mass, multi-stage fitness test and fractional exhaled nitric oxide (FeNO). Results: Aerobic fitness, FeNO and BMI were not significantly different between control and intervention at baseline. FeNO levels were 40.6±35.2ppb (range 7-150ppb), demonstrating high levels of inflammation in children with asthma (>35ppb). Relative to baseline, children in the intervention significantly improved their aerobic fitness at three months (p Conclusion: High intensity exercise improves aerobic fitness and maintains BMI in children with asthma. There was no reduction in airway inflammation suggesting it is not affected by level of fitness.