As you probably know, the largest organ of our body is our skin. What you might not know is that our skin is actually made up of three different types of skin: Hairy Skin, Mucocutaneous Skin and Glabrous Skin.
- Hairy Skin is the kind of skin that covers most of our body (though maybe some of us would rather it be less hairy).
- Mucocutaneous Skin is the type of skin on our lips and other body entry points.
- Glabrous Skin is the type of skin on your hands and feet.
It’s this last type of skin, Glabrous Skin, which interests me the most as a barefoot runner. The more I run barefoot, the more people ask me questions like, “Doesn’t it hurt?” Most of the time, I’m at a loss to explain why I like running barefoot and why, even when it hurts a little bit, it’s a good kind of hurt.
So I did what I always do when I don’t have an answer: I started reading.
What I found out, besides the three types of different skins, is that where we experience the sensation of pain (something too hot, too cold, too hard, too sharp, et cetera) is only through our skin. When something impacts our body from outside, we localize this pain and are able to detect where it comes from externally.
Interestingly, there are no pain receptors inside our body. Thus, when someone is having a heart attack, they often experience a “shooting pain” in the skin of their left arm. We can only “feel pain” externally.
And, of course, pain is really a good thing. It alerts our bodies to dangers and problems. I went to high school with a kid who literally didn’t feel pain. He had a cognitive break where he just couldn’t feel pain. He was continually cutting himself on things and burning his hands and body on items that were too hot.
What all that means, of course, is that for humans, feeling the sensation of pain is a positive thing. If we can’t feel things that are hurting us or could potentially hurt us, then we open ourselves up to the greater likelihood of injuries.
Glabrous Skin, the skin on our feet, like the skin covering our palms and fingers, happens to be more sensitive than some other skins on our body. This shouldn’t be mistaken by thinking that things hurt significantly more or less on the Glabrous Skin, but you should understand that this skin has more receptors covering it and is better able to differentiate tactile senses. And, of course, the greater number of receptors and input you are able to receive, the better the ability of your brain to differentiate between different types of stimuli.
As I was reading, I came across a finding by Dr. Michael Merzenich from the University of California, San Francisco. The book, The Brain that Changes Itself (by Dr. Norman Doidge), was particularly interesting. Although Drs. Doidge and Merzenich primarily express an interest in how the brain functions in old age and how one might combat the deterioration of brain function, their research hits on the idea that the sensory input we receive from our environment in walking barefoot could improve our motor function. Called proprioception, it essentially means that we can improve our balance, fall less and limit injuries while also increasing mobility just by going barefoot.
In other words, that little pain that we feel walking over pebbles, sticks or cement is good for us. All of the stimuli and sensation we feel through the ticklish Glabrous Skin of our feet helps us engage and thereby develop our brain and motor skills. The benefits of the simple act of removing our shoes shouldn’t be underestimated.
The next time someone asks you if running barefoot hurts, you can tell them honestly and knowledgeably, “A little bit. But it’s good. It’s making me smarter.”
~ Lucas M Peters