More seriously, this seems to be a reference to http://www.youtube.com/watch?v=8WaXPFIUJMk to me.
1.R: "You raise your body up like this, 'Yun!'"sfx: *streetch*
2.R: "And lower it like this, 'Yah!'"sfx: *fwap*
3.R: "Yun-yah! Yun-yah!"sfx: *thwap thwap*
4.R: "Alright, little ones, now you try!"Kos: "Yu-! Yu-!"
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