You haven't read it right?
I started doing parkour back in 2002/3 then for me it was the same like these: "Let's jump of big things and make a video."
In 2004 I changed and started to train "real" park our in the way David belle intended it.
I also trained with a guy who was pretty darn good.
In 2009 I quitted because of my study and other sports I focussed on.
During those years I've been very involved in the "hardcore" parkour scene. Hell, I even tried once with some guys from the original group that David Belle started ages ago.
I've amassed quite some knowledge about parkour, and I intend to share it to help your friends.
The drops they do aren't hard to just perform they just take some balls.
And whilst they aren't feeling it right now the way they land is putting incredible strain on their knees.
The force of landing from a height of 2m is pretty high. Now the Parkour roll is an excellent way to transfer the downwards energy into forwards energy. But almost no one can do a proper parkour roll. A Parkour roll isn't a judo roll and especially not a gymnastic roll over your spine, in a parkour roll not a single part of your spine will be in contact with the ground. A good parkour roll will be fluent and no speed will be lost.
Wait for 0:29 in this video, then you will see two excellent parkour rolls in a row. No the jumps aren't that big at all but his technique is flawless. Also watch the rest of the video for some great examples of good technique in parkour..
(And this is also one of the guys I used to train with.)
And please tell this to your friends.
I am a part of all that I have met. ~Alfred Lord Tennyson
And yes I'm Dutch.