Impact of varying physical activity levels on airway sensitivity and bronchodilation in healthy humans.

Publisher: Canadian Science Publishing Country of Publication: Canada NLM ID: 101264333 Publication Model: Print-Electronic Cited Medium: Internet ISSN: 1715-5320 (Electronic) Linking ISSN: 17155312 NLM ISO Abbreviation: Appl Physiol Nutr Metab Subsets: MEDLINE

Publication: 2011- : Ottawa, ON : Canadian Science Publishing
Original Publication: Ottawa, ON : National Research Council of Canada, c2006-

Inhalation* ; Motor Activity*; Bronchodilator Agents/*administration & dosage ; Lung/*drug effects ; Saline Solution, Hypertonic/*administration & dosage; Actigraphy ; Administration, Inhalation ; Cross-Sectional Studies ; Female ; Forced Expiratory Volume ; Healthy Volunteers ; Humans ; Kansas ; Linear Models ; Lung/physiology ; Lung Volume Measurements ; Male ; Models, Biological ; Nebulizers and Vaporizers ; Random Allocation ; Time Factors ; Vital Capacity ; Young Adult

The purpose of this study was to determine if the amount of physical activity influences airway sensitivity and bronchodilation in healthy subjects across a range of physical activity levels. Thirty healthy subjects (age, 21.9 ± 2.6 years; 13 men/17 women) with normal pulmonary function reported to the laboratory on 2 separate occasions where they were randomized to breathe either hypertonic saline (HS) (nebulized hypertonic saline (25%) for 20 min) or HS followed by 5 deep inspirations (DIs), which has been reported to bronchodilate the airways. Pulmonary function tests (PFTs) were performed prior to both conditions and following the HS breathing or 5 DIs. Moderate to vigorous physical activity (MVPA) level was measured via accelerometer worn for 7 days. Following the HS breathing, forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) significantly decreased from baseline by -11.8% ± 8.4% and -9.3% ± 6.7%, respectively. A 2-segment linear model determined significant relationships between MVPA and percent change in FEV1 (r = 0.50) and FVC (r = 0.55). MVPA above ∼497 and ∼500 min/week for FEV1 and FVC, respectively, resulted in minor additional improvements (p > 0.05) in PFTs following the HS breathing. Following the DIs, FEV1 and FVC decreased (p < 0.05) by -7.3% ± 8.6% and -5.7% ± 5.7%, respectively, from baseline, but were not related (p > 0.05) to MVPA. In conclusion, these data demonstrate that higher MVPA levels attenuated airway sensitivity but not bronchodilation in healthy subjects.

Keywords: airway responsiveness; différences liées au sexe; fonction pulmonaire; hypertonic saline; lung volume; pulmonary function; sensibilité des voies aériennes; sex differences; solution saline hypertonique; volume pulmonaire

0 (Bronchodilator Agents)
0 (Saline Solution, Hypertonic)

Date Created: 20151118 Date Completed: 20160907 Latest Revision: 20151125

20250114

10.1139/apnm-2015-0185

26575101