Curious Kids is a series for children of all ages. If you have a question you’d like an expert to answer, send it to [email protected].
Why do you have to wear a helmet when you’re skateboarding? – Artie, age 13, Queens, New York
Back when I was 13, I was an avid skateboarder – the kickflip was my go-to trick. And I didn’t see why I needed to strap on a helmet before practicing my ollies.
But now, doing the work I do, I get it.
My research is centered on understanding how physical forces cause brain injury and how to best protect against it. So I spend a lot of time thinking about how the brain gets hurt and how to improve helmets. This includes work focusing on protecting members of the United States military in training and active combat zones.
So why is it so important to wear a helmet when skateboarding, and also riding your bike, and really any sport or activity where your head could get hurt?
Your very own supercomputer
Inside your head sits probably your most amazing organ – your brain. It allows you to do everything you love, such as tasting ice cream, watching movies, listening to music and, of course, skateboarding.
Your brain is the world’s mightiest supercomputer. Everything it does requires billions of tiny brain cells, called neurons, working together in unison. These cells send messages to the rest of your body that regulate everything from body processes you’re not even aware of – such as your heartbeat – to moving your muscles, to helping you think and talk.
Some researchers estimate that humans have about 86 billion neurons, although scientists are still working on finding the exact number. That’s more than 10 times the number of all the people living on earth. And they’re all crammed inside a space the size of a melon, working together tirelessly, day in and day out.
Of course, your brain is not just made up of neurons. There are a lot of other cells supporting the neurons, including astrocytes and microglia, which are important helper cells to the neurons.
But as busy as your brain cells are, they are also incredibly soft and squishy. In fact, your brain has the consistency of jello. And like jello, it is very vulnerable, especially to physical forces, such as a fall or a sudden jolt.
The physical forces of a fall
Now, you might be thinking, doesn’t my skull protect my brain? And, yes, it does offer some protection. But your skull is a layer of cortical bone only about .28 inches (7 millimeters) thick, making it a useful barrier that prevents dirt and other objects from getting into your brain, but it’s too thin and too stiff to keep your brain safe in case of a fall while skateboarding.
Why is that? It helps to break down what happens when your unprotected head hits the pavement: Upon impact, your skull deforms, or changes shape, and often rotates. But your skull is not capable of fully absorbing that impact. So the…
