Athletic performance isn’t just what you’re physically capable of. It’s what you’re capable of within the context of what your brain is willing to endure for the risk and reward in a given moment. Your brain’s first job is to make sure you don’t die. So like a speed governor on a car, it won’t let you exert true maximum performance—which could leave you exhausted to the point of being vulnerable—unless the stakes are high enough. It will shut you down at a lower physical “limit” if the risk of exertion isn’t worth the reward.
