Smith Joshua R, Kurti Stephanie P, Johnson Ariel M, Kolmer Sarah A, Harms Craig
Department of Kinesiology, Kansas State University, 1A Natatorium, Manhattan, KS 66506, USA.
Appl Physiol Nutr Metab. 2015 Dec;40(12):1287-93. doi: 10.1139/apnm-2015-0185. Epub 2015 Aug 26.
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.
本研究的目的是确定在一系列身体活动水平上，身体活动量是否会影响健康受试者的气道敏感性和支气管扩张。30名肺功能正常的健康受试者（年龄，21.9±2.6岁；13名男性/17名女性）分两次到实验室报到，在实验室中他们被随机分配，分别吸入高渗盐水（HS）（雾化高渗盐水（25%）20分钟）或先吸入HS，然后进行5次深呼吸（DIs），据报道后者可使气道扩张。在两种情况之前以及HS呼吸或5次DIs之后均进行了肺功能测试（PFTs）。通过佩戴7天的加速度计测量中度至剧烈身体活动（MVPA）水平。在HS呼吸后，第1秒用力呼气量（FEV1）和用力肺活量（FVC）较基线水平显著下降，分别下降了-11.8%±8.4%和-9.3%±6.7%。一个两段线性模型确定了MVPA与FEV1（r = 0.50）和FVC（r = 0.55）的百分比变化之间存在显著关系。对于FEV1和FVC，每周MVPA分别高于约497和500分钟，在HS呼吸后PFTs有轻微的额外改善（p>0.05）。在进行DIs后，FEV1和FVC较基线水平分别下降了-7.3%±8.6%和-5.7%±5.7%（p<0.05），但与MVPA无关（p>0.05）。总之，这些数据表明，在健康受试者中，较高的MVPA水平可减弱气道敏感性，但不能增强支气管扩张。
