One of the most important things that neuroscience research is illuminating is that the traditional mind/body separation is an illusion. Everything that we are learning about the brain points toward a reality in which the two are more connected than we can imagine. In fact, recent research around willpower and our ability to resist temptation and perform hard work suggests that mental and physical fatigue may be inseparable.
Via Medical News Today:
“Cognitive tasks, as well as emotional tasks such as regulating your emotions, can deplete your self-regulatory capacity to exercise,” says Kathleen Martin Ginis, associate professor of kinesiology at McMaster University, and lead author of the study.
Martin Ginis and her colleague Steven Bray used a Stroop test to deplete the self-regulatory capacity of volunteers in the study. (A Stroop test consists of words associated with colours but printed in a different colour. For example, “red” is printed in blue ink.) Subjects were asked to say the colour on the screen, trying to resist the temptation to blurt out the printed word instead of the colour itself.
“After we used this cognitive task to deplete participants’ self-regulatory capacity, they didn’t exercise as hard as participants who had not performed the task. The more people “dogged it” after the cognitive task, the more likely they were to skip their exercise sessions over the next 8 weeks. “You only have so much willpower.”
These results aren’t necessarily surprising. Anybody who’s spent a long day doing hard mental work knows the feeling of being depleted, and how the idea of going out for a run sounds a lot less attractive than it does on a bright Sunday morning. But they do carry implications for sport. Athletes’ ability to exercise only so much willpower ought to remain up front in coaches’ minds when they structure practice. If the goal for the day is a hard, physical workout, it might not be ideal to schedule several hours of film beforehand. If the most important part of the day is a strategy or film session, then it might be better for that to come first.
On a related note, researchers at the University of Cape Town are developing methods to collect fMRI images of cyclists’ brains as they ride to exhaustion. With this research, neuroscientists ought to be able to begin uncovering the neural mechanisms behind fatigue, something that has previously been impossible.