Biologists have found that the thickness and hardness of a callus doesn’t affect the foot’s sensitivity, in a study published in Nature on June 26. Using a custom-built device that applies pressure to the skin, study participants pushed a button when they felt a poke.
“People who had thicker calluses had no loss of sensitivity,” says coauthor Daniel Lieberman of Harvard University to Science News. Forming calluses doesn’t “exert a cost in terms of our ability to sense the ground underneath us,” says Lieberman.
N.B. Holowka et al., “Foot callus thickness does not trade off protection for tactile sensitivity during walking,” Nature, doi:10.1038/s41586-019-1345-6, 2019.