A late colleague of mine once told me that as a student back in the 90s she had had a very nerdy, strict, old-school style female teacher who used to stand in front of the class with her hair in a bun.

When the class went on an excursion, that teacher, to everyone´s utter surprise, opened her bun to reveal a perfect knee-length mane, and went on to really destroy everybody at table-tennis, including even the most skillful, fastest, and sportiest of boys - to everybody´s surprise, again.