oh yeah, I would definately buy a helmet.
Last year my GF forgot her helmet and open track was kind enough to let her barrow one. But when she plopped it on, she started screaming EEWWWW!!!! and quickly yanked it of... What we didn't know is that someone else had used it a little while ago and was full of nasty sweat inside!
Other than long pants, thats all you need.
