Rock 2 - Exercise
“Good things come to those who sweat.”
We Are Built To Move
Our next rock is exercise. We all know how important exercise is for our bodies. The idea that 20-30 mins a day of aerobic exercise is good for the health of the heart, the cardio-vascular system and our core strength is common. What we perhaps don’t know is that exercise is as important for the health and functioning of our brains and the minds they produce as well.
Just 300,000 years ago, an eye-blink in evolutionary time, humans were running around the African savannah chasing down their food or running away from predators. We moved every single day, foraging for meals, exploring our range.
Our brains and bodies have been built with a certain expectation about the levels of exercise we should be doing every day. And here again, with this second of our hallowed rocks, we see the dangerous impact of our 21st century life-style on our bodies and brains. Sitting still at desks or in front of screens is for our current generation, the new smoking. It is doing so many of us real harm.
Exercise creates more of a hormone called brain-derived neurotrophic factor (BDNF). What does this do? A range of different things, but at the level of the neurone it causes them to sprout more connections (dendrites). This increase in connections happens differentially in our pre-frontal cortex (PFC) the swankiest bit of our evolutionary brain kit, the part of the brain that helps us manage and control goal-orientated behaviour and our impulses. Exercise also increases blood flow to the brain and encourages the capillaries that feed neurones to grow.