The Effect of Inhaled Nitric Oxide on Maximal Oxygen Consumption During Exercise in Hypoxia

• Status: Recruiting
• Trial end date: 2022-12-01
• Target enrollment: 0
• Participant gender: All

Summary

During exercise in conditions of low oxygen (termed hypoxia), such as mountaineering at high altitudes, the lung blood vessels constrict in an attempt to protect the body from the negative effects of hypoxia. It appears that this blood vessel constriction may limit the heart to pump blood during heavy exercise, leading to reductions in exercise performance. Inhaled nitric oxide is a drug that is known to relax the lung blood vessels. Inhaled nitric oxide has been used to relax lung blood vessels and improve exercise capacity in patients with chronic disease. It is unknown if similar improvements would be observed during exercise in healthy individuals when exposed to low levels of oxygen. The goal of this study is to determine if inhaled nitric oxide can relax the lung blood vessels and improve the heart's pumping ability during exercise in low oxygen conditions. Further, the investigators will determine if these improvements in lung blood vessel and heart function increase exercise performance. Participants will complete 6 sessions over a three week period where they will perform exercise challenges while breathing low levels of oxygen with and without inhaled nitric oxide. The low oxygen conditions will be comparable to being at an altitude of 14,000-17,000 feet. 17,000 feet would be equivalent to standing on the summit of King Peak in the Yukon (the 4th tallest mountain in Canada).

• Phase: Phase 1/Phase 2
• Accepts Healthy Volunteers?: Accepts Healthy Volunteers

Details

• Lead Sponsor: University of Alberta
• Treatments: Nitric Oxide

Criteria

Inclusion Criteria:

• Non-smokers and less than 10 pack years smoking history

• Young healthy males and females with normal lung function and no known history of cardiopulmonary disease.

Exclusion Criteria:

• Individuals with significant cardiovascular, metabolic, neuromuscular or any other disease that could contribute to abnormal respiratory and cardiovascular responses to exercise will be excluded.

• Individuals with musculoskeletal injuries that prevent them from completing cycle ergometry exercise trials will be excluded.

• For safety reasons, pregnant females will be excluded.

• Participants currently on oral steroids (i.e. prednisone) or phosphodiesterase type 5 (PDE5) inhibitors will be excluded.