I used to be a hardcore parkour kid in elementary school with my friend. We didn't know wtf parkour was though. We used to climb on top of those big metal things that hold all the equipment can't remember the names, we would do frontflips and backflips off them, we would do backflips off swings, we would do backflips off the playground bridge. We were actually insanely good for 5th graders. I can't even do a frontflip or backflip now and I don't have near as much guts as I did. Also I almost got suspended because the proctors kept telling me to stop doing backflips and I'd try to sneak it by when they weren't looking.
that's not parkour. if it takes you 10 seconds to get up a wall your own height... that means you're normal. climbing ladders is also quite normal behavior.
