The younger teen utterly trashed one of my ergonomic chairs that I'd had for five years at that point - back flapping loose, screws holding it together knocked out. She's 157cm (5'2") and weighs about 55kg (120lb). I have no idea how the hell she managed this.

I'm 194cm/95-100kg and have nothing like this sort of trail of trashed chairs. (One whose back plastic warped badly from being kept too near an open fire.) I'm thinking it's less height and weight and more sheer talent.