As one ascends to higher altitudes, the air becomes ‘thinner’, meaning there is a substantial decrease in the availability of oxygen. A reduction in oxygen disrupts the brain’s ability to perform some of its most complex processes including decision-making and memory (generally referred to cognitive function).
As you might expect, these processes progressively deteriorate as the amount (atmospheric pressure) of oxygen decreases. Impaired cognitive function has a number of implications for an individual’s ability to perform complex tasks at high altitude, which ultimately can seriously compromise an individual’s overall safety.
Exercise to the Rescue?
Performing a single session of aerobic exercise (cycling, walking, running, etc.) at sea level improves these same cognitive functions for up to an hour after completion of exercise. This is really cool because we can strategically use an exercise session to boost our mental capacity, especially if we’re feeling low (study break anyone?).
You might expect that exercising at high altitude would not elicit the same brain-boosting benefits due to the lack of oxygen; however, emerging research suggests the opposite! Researchers found that breathing air with low oxygen impaired cognitive function in healthy adults. However, performing 20 minutes of cycling while breathing low oxygen restored cognitive function to sea level values.
What remains to be explored, and is my research question for the trek, is whether a single exercise session retains the ability to improve cognitive function in individuals living at high altitude for multiple days.
To answer this question, we will measure cognitive function (using tests on a computer) and brain activity (using EEG) before and after a 20-minute session of brisk walking at 3 different locations on the Everest Base Camp trek.