They paddle faster, and faster, and faster, until they're going so fast that they literally lift up out of the water, and they're standing upright, sort of paddling the top of the water.
水掻きをドンドン速くするとスピードが上がり やがて体が湖面から浮上して 背中をピンと伸ばしたまま 足が水面を漕ぎだします