We had gym uniforms in junior high/middle school. They were double thick cotton T's with light blue on one side and dark red on the other. And twill elastic waist shorts in light blue. They were issued to us and we were required to keep them clean. I remember that double sided t's were so fricken HOT because they were so thick! We'd have to go back into the locker room and flip them inside out depending on which team you were on.

Oh, and you could tell when someone's parents weren't paying attention to the laundry because if you washed them in anything but cold, the red would bleed through to the blue and you'd have a mottled purplely colored jersey that didn't match either team!