In the final fight scene, Frank Dux (played by Jean Claude Van Damme) is fighting Chong Li. After Chong Li throws the salt, or powder in Dux's eyes, he goes into this flashback sort of thing. Obviously, this is a tough fight, so Dux is sweating hard and his hair is all messed up and sweaty, as well as his face. After he finishes his flashbacks and kicks Chong Li, it shows him again and now his hair is nice and styled (and Dry). And his face is also dry at this point. Another funny thing is, they forgot about the hair, but remembered the blood coming out of his nose.