How do you prevent pony tail dents?

I get really bad pony tail dents! I'll put my hair up in a pony tail for as short as 5 minutes and i get a huge (and i mean HUGE!!!!!)dent (and my hair is naturaly strait!!!)! I need advice; i cant go on looking like a fairy-tale-peasant-little-girl-person! But, don't tell me: "don't put it in a pony tail" because i am on the bball team and i can't play without it in a pony tail! Meaning its stuck in a pony tail for like 2 hours everymorning! AHHHHHH! PL3A53 H3LP!