EDIRNE, Turkey—Turkish oil wrestling is all about the leather britches.

For three days this weekend, some 1,500 men—from 11-year-old striplings to improbably muscled Goliaths—donned long, thick, black pants made of water-buffalo and cowhide. Then, they doused themselves in olive oil from head to toe and strode into a grassy gladiatorial arena.

It's...