Due to last week's family schedule, I didn't get to skate during the week, so I went to Skaters' Edge Friday night to ride the "snowman" bowl. During the course of the session I rode with a four year old (well, and 11 months) and a 48 year old. They were both pretty good. The four year old dropped into the 8' deep end, no problem.
Below, not me, but it should give you the idea:
It isn't apparent when you're watching what a tiring workout it is.