A few days ago I was practicing swinging around on bars, the no-frills unpainted steel kind, for the first time in a long while. Within fifteen minutes of beginning I had ripped a patch of skin off my left hand from that the area below the knuckles where the skin folds together when you're pinching your fingers and thumb towards each other (AKA pinch grip). After a few more minutes I had torn two calluses from just below the fingers on the same hand, and a callus on the right hand was threatening to go as well. This sort of thing happens a lot when you're new (or newly returned) to swinging around on bars. But the old Instagram post (above) reminded me that there's a long-term method to preventing calluses ripping too often: developing a whole hand callus. All credit for this idea goes to Katy Bowman, who has covered the topic a bunch of times on her site and podcast, including the science behind it.
The challenge to building a whole hand (or foot, or both!) callus is that it requires exposure to a variety of surfaces, loading patterns, and intensities. I know why I ripped this set of calluses so quickly: I had only been hanging and doing simple uni-directional movements on smooth and predictable surfaces, predominately olympic rings, for a while, and had definitely not done any dynamic swinging movements on any surface for some time too. The smooth metal and wood surfaces you find in urban areas, parks, or in the gym are a good place to start, but as with me, if that's the only kind of surface you hang and swing from odds are you'll keep ripping calluses on the regular. The fix to that, as Katy articulates better than I will, is to more surfaces into the mix. Practically speaking that's going to be natural surfaces, trees and rocks, and different textures of the urban landscape—concrete walls, brick walls, rock walls, or finding those terribly uncomfortable square bars and railings. For the purposes of the big monkey-like swings though it's not just the surface, but also the force of that movement that needs to be replicated with these different surfaces. Personally that's the greatest challenge, as suitable trees for those big moves are hard to come by in the forests of North Carolina, which are dominated by pine trees with no sturdy branches anywhere near the ground.
All this is to say is for me this remains an unproven theory and a reminder to continue working on developing a more uniform callus across both my hands and feet; I'm doing way better in that regard with the feet, but it's easier to get that variety of exposure for your feet if you're walking barefoot, though the arch needs improvement for specific types of climbing techniques.