My girl has wrestled for several years now and I can tell you most refs wont let them wrestle in a swimming cap. They say it gets to much traction on the mat and could hurt thier neck. Most refs are pretty good guys and they let the hair hang down a little. But there is one ref by the name of Don Johnson who will not tolerate any of that hair out of a net, thats is, if its below your collar. But if you are a boy wrestler its OK with him. Hes nothing like the Don Johnson from Miami Vice!