Recruiting

Ozone

Sponsor:

University of British Columbia

Code:

NCT05105529

Conditions

Asthma

Asthma, Exercise-Induced

Exercise Induced Asthma

Exercise Induced Bronchospasm

Eligibility Criteria

Sex: All

Age: 18 - 50

Healthy Volunteers: Not accepted

Interventions

Exercise

Ozone

Filtere Air

Study Details

Brief summary:

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.

Conditions

Asthma

Asthma, Exercise-Induced

Exercise Induced Asthma

Exercise Induced Bronchospasm

Study ID

NCT05105529

Start date

Jan 1, 2021

Status verified date

May, 2022

Completion date

Feb, 2023

Anticipated

Primary completion date

Jan, 2023

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18 - 50

Healthy Volunteers: Not accepted

Inclusion Criteria:

  • 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

Exclusion Criteria:

  • 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

Study Design

Enrollment

40 participants

Anticipated

Allocation

Randomized

Intervention Model

Crossover

Primary purpose

Basic Science

Interventions and Outcome Measures

Arms

experimental: 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.

sham comparator: 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.

Interventions

Exercise

Cycling at 60% of VO2max on a cycle ergometer for 30 minutes

Ozone

Breathing 170ppb ozone

Filtere Air

Breathing filtered air

Primary outcome measure

  • Change in FEV1 from baseline to 10 minutes after exercise [ Time Frame: Measured at baseline and 10 minutes after each exercise bout ]
  • Change in FVC from baseline to 10 minutes after exercise [ Time Frame: Measured at baseline and 10 minutes after each exercise bout ]
  • Change in FEF25-75 from baseline to 10 minutes after exercise [ Time Frame: Measured at baseline and 10 minutes after each exercise bout ]

Central Contacts and Locations

Central contacts

Patric O Gonçalves, BScPT

6048229331patricog@alumni.ubc.ca

Michael Koehle

michael.koehle@icloud.com

Locations

Environmental Physiology Laboratory

Recruiting

Vancouver, British Columbia, Canada, V6T 1Z1

Contacts

Michael Koehle, MD, PhD

604 8229331michael.koehle@ubc.ca

Principal Investigator:

Michael Koehle, MD, PhD

University of British Columbia

Recruiting

Vancouver, British Columbia, Canada, V6T 1Z3

Contacts

Michael Koehle, MD, PhD

(604) 822-9331michael.koehle@ubc.ca

Principal Investigator:

Michael Koehle, MD, PhD

More Information

Sponsor

University of British Columbia

Last update posted

Jun 2, 2022

Last verified

May, 2022

Keywords

  • Ozone
  • Air pollution
  • Asthma
  • Exercise-induced bronchoconstriction

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by University of British Columbia on 2022-06-02.