Title: “Exercise-induced arterial hypoxaemia in female master athletes”
Thesis Supervisor: Dr. Bill Sheel
Committee Members: Dr. McKenzie, Dr. Koehle, Dr. McKinney, Dr. Inglis (chair)
Abstract:
The capacity of the normal lung is “overbuilt” and exceeds the demand for pulmonary oxygen transport in the healthy, exercising human. However, in some highly fit individuals the lung’s diffusion surface, airways, and/or chest wall musculature are underbuilt relative to the demand for maximal oxygen transport. The lungs do not adapt to the “training stimulus” to the same extent as do other links in the oxygen transport scheme resulting in a relatively “underbuilt” pulmonary system and a reduction in the amount of oxygen in the blood – a phenomenon called exercise induced arterial hypoxemia (EIAH). Approximately 50% of young male endurance athletes exhibit EIAH with few studies documenting the occurring of EIAH in women. The ‘normal biology of aging’ impacts the respiratory system with well documented decrements in pulmonary function. For example, there is a progressive decline in lung elastic recoil and diffusion surface area. Little-to-no attention has been given to the female master (40+ years) athlete population in terms of EIAH. This study will determine the relative prevalence of EIAH in endurance trained female masters athletes. Participants will have their resting pulmonary function and exercise capacity assessed on day one. On day two, participants will be instrumented with a radial artery catheter, and oesophageal temperature thermistor to perform detailed gas and lung mechanics measures during three constant load exercise tests (50%, 75% and 90-95% VO2max). The proposed work will advance our understanding of the complex interrelationships between aging and training induced changes to the components of oxygen delivery in an understudied group.