 
Calluses occur in response to repeated pressure and friction. Calluses on the soles of your feet usually develop according to your walking patterns. Most people associate the idea of calluses as a negative but they are fairly natural and many develop them in different places out of the necessity of our daily lives.
I am sporting new calluses across the four fingers of my left hand as I am trying to learn how to play a guitar. At this moment in time I couldn’t imagine the process without them. The tips of my fingers are still a little tender even with the calluses. Over the summer I developed a callus on the outside of one of my big toes from the sandals I was wearing. This callus didn’t make me happy but now a month or so into fall weather it is rapidly disappearing.
Before children entered my world and I prioritized a hardcore yoga practice I used to love to do ten minute headstands. At the time I developed a callus on the top of my head and would be totally weirded out anytime it peeled, especially the first time when it started flaking off and I had I had clue what is was.
I don’t necessarily think calluses on your feet are bad for you depending on where they develop. You can get an idea of how well you walk by where on your feet calluses form. The picture at the top indicates three spots that wouldn’t be bad for calluses to develop. Most everyone starts their footfall on the outer heel because there is no bone to land upon on the inside of the foot, so that is where you would want to develop that heel callus. The inner heel is just a cushiony pad. You can see in the picture below that the calcaneus bone is thinner than the heel itself.
The footfall should proceed from the inner heel across the center of the foot which ideally doesn’t touch the ground before rolling to the outer ball of the foot and then across to the inner ball and big toe for push off.
So callusing in these spots– inner heal outer ball and inner ball— is okay (or across the whole ball if it is even). The main reason our feet wouldn’t callus, other than pedicures, would be because our shoes provide too much cushion as to not suffer the wear and friction that leads to calluses. But our feet are mean to be quite mobile and adaptable to surfaces. In my mind a lack of callus suggests a lack of contact which isn’t good.
I used to walk predominantly on the outsides of my feet and since relearning how to walk my calluses have changed from the outer foot and moved more towards the middle of the ball of the foot. Nowadays, I am barefoot or wearing minimal shoes a lot and I hope over time that I can get the inner foot to develop more of a callus because it would mean I was getting a better footfall more consistently.
Where do your feet callus?
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