Three sets of carefully timed oscillometry and dyspnea score measurements will be performed: 1) at "baseline", before the participant receives their scheduled dose of LABD and roughly 4 hours following a scheduled dose of SABD; 2) between 15-20 min after having received their next scheduled dose of SABD and just preceding their next scheduled dose of LABD (SABD only); and 3) after having received the scheduled dose of LABD and between 25-35min of the most recent SABD administration (LABD + SABD), such that there is overlap in the time window of SABD and LABD onset at the time of the third set of testing.
