The impact of a heat and moisture exchange mask on respiratory symptoms and airway response to exercise in asthma

Respiratory symptoms, including cough are prevalent in asthmatic individuals when exercising. This study investigates whether a heat and moisture exchanger (HME) face mask is effective in modulating exercise induced bronchoconstriction (EIB) and post exercise cough in a cold, dry environment in asthmatic individuals.

Twenty-six participants diagnosed with asthma (20 males, 6 females) completed three cycling exercise challenges (EX) at 8 oC and 24% relative humidity (RH) in a randomised order. Participants wore either an HME mask (MASK), sham mask (SHAM), or no mask (CON). Following a 3-min warm-up participants completed 6-min cycling at 80% peak power output. Before and after EX, maximal flow volume loops were recorded. Post EX cough was monitored with a Leicester Cough Monitor (LCM) for 24-hours.  Results were analysed using repeated measures ANOVA and Friedman’s tests and data presented as the mean ± SD or median (IQR).

Eleven participants failed to demonstrate EIB (i.e.>10% ...