My commentary from our Facebook page: Just in case you saw this (ladies) and believe that you are genetically designed NOT to be able to do a pull-up, sorry. How many kinesiologists think that the human body can improve a life-long hole in a strength-to-weight ratio in 12 weeks of thrice-weekly exercises while attempting to lose mass and doing general upper-body exercises? And the leverage argument? Sorry again. Sure, it’s more difficult to fill the strength deficit, but that’s all. Long arms do not equal a genetic out. But if you’ve got long limbs it is waaay better to not let your strength go as a kid cuz it does take more work which means more food to fuel more work=bonus.
Everyone knows (hopefully) that the reason you exercise is to adapt the tissues of your body. The body does not adapt in general, however. Meaning that just because you have a few strong areas does not mean that you are strong all over. You can still have an Achilles heel. A weak spot. Missing scales on a dragon’s left breast plate that are easily penetrated by an arrow shot by one Bilbo Baggins (P.S. Commenting on that last reference will only out you as a huge nerd, which only makes me love you more). But guess what, this post is not about a pull-up. It’s about skin. And not just any skin. Weak skin.
There are lots of visual signs you can learn to read that give you insight into how you use your body and calluses are one of them. A lack of calluses is also a sign. Take a look at your hands and read the story your body is telling. Do you see evidence of your lifelong habits?
Believe it or not, when it comes to closing the upper-body strength gap, what gets in most people’s way is the weakness of their skin. Skin does not have muscle, but it actively thickens over time in response to different types of loading. Skin can adapt to pressure, but what really makes it thicken into a callus is a shear force.
A shear force is when one tissue (in this case, the skin) is pulled in opposing directions. Consider the palm of your hand while hanging:
You can see that the hand, sliding (even slightly) around the bar creates a shear force on the palm. But if you take a closer look at the layers of skin, the shear force is really between the topmost and subsequent layers of the skin:
When you take super-unloaded skin (that’s skin that hasn’t done a lick of work in its entire life) and load your body weight onto it, this shear force often rips the fresh skin. Viola! You’ve just made either a flesh wound or a blister. These are both signs that you tried to jump the skin-strength gap a little quickly. Ideally your skin would have been gently loaded throughout a lifetime, when you weighed less and “hung around” more frequently.
Callused skin is actually an area of strength in skin that has much better circulation than other areas and are a necessary part of the kinetic chain when it comes to movement. But wait! You thought that a callus was something that was unhealthy, right? When you get a little callus, because of repeated friction (like a corn on your toe or a tiny area of callus on the sole of your foot), this small patch of “health” becomes like a rock in a shoe (or a pea under a mattress if you’re a princess). Ideally, calluses should be developed widely — across the entire palmar surfaces of the hands and feet. We need strength in these tissues to really optimize the whole-body strength actions of both the upper and lower body.
And, now that you know how skin works, you can probably answer this reader’s question about his feet:
I’m trying to spend more time walking barefoot, but my feet are sooooo sensitive. Every little pebble, rock, or pillbug is a problem for me. The muscles of my feet don’t mind going barefoot, but it’s torture to the skin. It’s like The Princess and the Pea, but with walking instead of sleeping.
When I was a kid, I went barefoot all the time, even spending a year in Borneo without a pair of shoes. I remember being barefoot without issues until 12 or 13, then it’s a blur… What has happened to me? How can I get that back?
Dear Princess-Footed Sir,
What has happened to you is this: your skin has atrophied since those barefoot in Borneo days of yesteryear. Just like your body does not maintain unused muscle, the body will let skin atrophy if the skin itself is not loaded. My guess is the last 20-something years of keeping the foot skin tension and traction-free means that even with the arms, legs and torso of a god, it appears you literally have the foot-skin of a little wuss.
But why take my word for it when you could take my book’s word for it instead? Here’s a swiped paragraph (because I’m too lazy to write it out again…):
“The optimal way for getting super-regenerating skin would be to allow our foot to interact with natural surfaces outside of the shoe over a lifetime, prompting a slow adaptation in foot skin thickness over that lifetime, giving us a much better ability to cope with the sensations caused by walking barefoot.” – Katy Bowman, Every Woman’s Guide to Foot Pain Relief.
Familiar with “a bed of nails”? I’m not going to explain how it works (you can read about it here), but basically the lack of a full-footed callus means everything you step on creates a higher amount of pressure. Everything you step on acts like a single nail.
If you were appropriately callused for your weight and environment, everything you stepped on wouldn’t hurt as much because you’d be distributing the pressure.
Now for those of you who email me, sending pictures of your blisters and jacked up feet following “the time you thought it would be fun to go barefoot for a 5K with minimal training,” here’s the skinny on surfaces.
I am a much bigger fan of natural surfaces when it comes to bare feet because the skin often takes a much greater beating on man-made stuff. This doesn’t have to do with the hardness of the surface, but how a surface is connected to itself.
Natural surfaces are not fused. The top layers move freely over the lower layers. So when you’re walking or running and push back to move forward, there is much less shear force on the skin because a tiny portion of the top layer of the ground moves back with the foot.
Man-made surfaces are firmly connected throughout and increase the tension and shear on the skin. And, when the surface is porous, like asphalt, it can act like teeth grabbing into the skin. Not a place to begin your barefoot habits.
In case you were wondering why these pictures are so crappy? I only had one hand to draw them with.
And in case you were wondering if I lead a glamorous life? I was pantsed by my 18-month old while drawing pictures with one hand.