One muscular youngster and five children in almost every wagon, making the loudest possible racket. And constantly screaming YARE YARE, which means to perform (i.e. to get the float to move with all those muscles). I've also heard it's some kind of archaic Japanese, but there's no way of knowing what it means in that context.
taken on 2 August 2017, 20:22
location: Sansha Festival in Hachinohe, Aomori, Japan