So says this research study claiming what we all knew: cotton socks are blister bait.

Biological engineering students at the University of Missouri-Columbia tested 10 popular brands of athletic socks and separated the good from the bad with a device that measured moisture and friction, which causes blisters.

All-cotton socks are most likely to cause blisters on sweaty feet, according to research data, while nylon socks performed the best. Socks that were a cotton-synthetic blend scored somewhere between the two.

The study also noted that it’s the fabric — not the price or brand — that determines relative likelihood of blistering.