underwear

UNDERWEAR FOR CHAMPIONS. All Male players, and those Mighty Studs in particular, are highly commended to wear those elastic pants to prevent urologic dysfunctions. Liu Shiwen wearing therapeutical pants. Again, the compressional underwears will make your legs stronger...

According to this video, Jun Mizutani admits he doesnt wear underwear when playing table tennis. Bonus: Koki Niwa's chikita Due to my bad japanese, I cant translate much :P