Constrained swelling buckles skin

Moisture under clothing may make healing skin easier to damage by friction. This hypothesis asks whether swelling buckles its outer layer. The proposed test holds fluid, temperature and hydration at each skin depth constant, then changes lateral restraint. A restrained surface layer may swell more than the layer attached below, creating compression and folds before friction. Free expansion should keep it flatter and preserve strength in later friction, even with protease-free fluid. A rival mechanism says sweat proteases, enzymes that cut cell-to-cell junction proteins, weaken skin while its shape stays unchanged. Measuring folds and strength could distinguish contributions to healing skin.