Kana is specifically talking about the Japanese "ouendan" style of cheering, which is more like a military drill than a gymnastics act; hence the uniforms. (It's the same reason Sakaki wore a male uniform at one point in AzuDai, to Kaorin's great excitement.) "Again!!" by Mitsurou Kubo is a good ouendan manga.
FujiKana 76Ah! Pictures from the sports festival!*flip*Yep.Minami, you really surprised me by wearing a gakuran out of the blue like that while you were cheering!Well, yeah, but it won't feel like I'm cheering properly if I don't wear it, right?Yeah! It looked really great on you too!You think? I even had to go out of my way to get Akira to loan me his!Hehe!Wha-!?*shocked*
