Pulmonary and Vascular Adaptations to a 5-days Exercise Protocol in Ozone in Physically Active Individuals With Asthma and Exercise-induced Bronchoconstriction
试验速览
- 阶段
- 不适用
- 入组人数
- 40
- 试验地点
- 2
- 主要终点
- Change in FEV1 from baseline to 10 minutes after exercise
研究概览
简要总结
Researchers found that impairments in the cardiopulmonary system caused by acute exposure to ozone were outweighed by repeated exposures to ozone. The goal of this study is to confirm there will be an adaptation similar to what was previously proved but in individuals with asthma and exercise-induced bronchoconstriction (EIB). The purpose is to examine adaptive responses in a randomized cross-over trial in which physically active individuals will perform submaximal exercise on five days in ozone and filtered air exposures separated by a washout period.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Basic Science
- 盲法
- Triple (Participant, Care Provider, Outcomes Assessor)
盲法说明
Air quality condition (Ozone and filtered air) will be double-blinded; Participants will not be told at any time before the study completion to which group they are assigned (intervention or sham)
入排标准
- 年龄范围
- 18 Years 至 50 Years（Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Recreationally active individuals
- •Diagnosed asthma and/or mild exercise-induced bronchoconstriction: defined by an FEV1 fall equal to or greater than 10% but lower than 25% in the eucapnic hyperventilatory test.
- •Able to securely perform a maximal exercise test (responded 'no' to all questions on the PAR-Q+ questionnaire)
- •Able to communicate in English
排除标准
- •Diagnosed with any cardiorespiratory or vascular diseases
- •Pregnant or potentially pregnant
- •Non-smoking
- •Lower limb musculoskeletal injury or lower limb limitation to cycle on a bicycle ergometer
- •Recent respiratory symptoms or upper tract infection within 4 weeks
- •On vitamin (e.g., C or E) supplementation
研究组 & 干预措施
Ozone (O3) group
Participants of the experimental group will perform sub-maximal exercise (60% of VO2max for 30 minutes) on a cycle ergometer while inhaling 170ppb ozone delivered continuously during each exercise session.
干预措施: Exercise (Behavioral)
Filtered Air
Participants of the sham group will also perform sub-maximal exercise (60% of VO2max for 30 minutes) on a cycle ergometer similar to intervention. However, only in this group, the ozone generator will not be activated so that just filtered air will be delivered to the participant while performing each exercise session.
干预措施: Exercise (Behavioral)
Filtered Air
Participants of the sham group will also perform sub-maximal exercise (60% of VO2max for 30 minutes) on a cycle ergometer similar to intervention. However, only in this group, the ozone generator will not be activated so that just filtered air will be delivered to the participant while performing each exercise session.
干预措施: Filtere Air (Other)
Ozone (O3) group
Participants of the experimental group will perform sub-maximal exercise (60% of VO2max for 30 minutes) on a cycle ergometer while inhaling 170ppb ozone delivered continuously during each exercise session.
干预措施: Ozone (Other)
结局指标
主要结局
Change in FEV1 from baseline to 10 minutes after exercise
时间窗: Measured at baseline and 10 minutes after each exercise bout
Measurement of pulmonary function: forced exhaled volume in the first second (FEV1) in liters
Change in FEF25-75 from baseline to 10 minutes after exercise
时间窗: Measured at baseline and 10 minutes after each exercise bout
Measurement of pulmonary function: forced expiratory flow at 25-75% of pulmonary volume in liters per second (L/s)
Change in FVC from baseline to 10 minutes after exercise
时间窗: Measured at baseline and 10 minutes after each exercise bout
Measurement of pulmonary function: forced vital capacity (FVC) in liters
次要结局
- Change in Pulse Wave Velocity (PWV) from baseline to 20 minutes after exercise(Measured at baseline and 20 minutes after each exercise bout)
- Change in Fraction of exhaled nitric oxide (FeNO) from baseline to 5 minutes after exercise(Measured at baseline and 5 minutes after each exercise bout)
研究者
Michael Koehle
Professor
University of British Columbia