title: Exercise and nasal patency.
abstract: Nasal airflow resistances were studied in 20 healthy subjects at rest, with exercise, and during recovery from exercise. Resistances were first measured under resting conditions. As a basis for comparison 0.1% xylometazoline was applied by insufflation; it reduced nasal resistance by an average of 49%. On a subsequent occasion, the degree and time course of changes in resistance were measured 1) during 5-min exercise bouts at rest 25, 50, and 75% of predicted maximum O2 intake (VO2max), 2) during 5-, 10-, and 15-min exercise bouts at 50% of VO2max, and 3) during recovery from exercise. Resistance decreased with intensity but not duration of exercise; an initial sudden decrease was followed by a more gradual but progressive decrease, which continued for several minutes following vigorous short duration exercise. Thus following 5 min of effort at 75% of VO2max, resistance reached a nadir (46% fall) 5 min after cessation of exercise. Recovery of preexercise values required 5 min after 5 min of exercise at 25% of VO2max and 10 min after 5 min of exercise at 50% of VO2max. Some decrease persisted 15 min after 5 min of exercise at 75% of VO2max.
mesh_terms: D000328:Adult; D000403:Airway Resistance / Q000187:drug effects; D005260:Female; D006801:Humans; D007093:Imidazoles / Q000494:pharmacology; D008297:Male; D009666:Nose / Q000502:physiology*; D005082:Physical Exertion; D012123:Pulmonary Ventilation / Q000187:drug effects; D013997:Time Factors
chemical_list: D007093:Imidazoles; C009695:xylometazoline