I hope no one gets upset but I have to ask this.
I'm not a mtn biker but my 33 year old son is. He doesn't ride the trails or off road for long distances. When he has to ride it isn't very far, maybe 1 or 2 miles tops. He primarily does what I'll call "stunts". He likes doing things like jumping off the roof of his shed, short drops on the trail (usually less than a 20 foot drop), or jumping over stumps and rocks.
I'm a roadie and don't understand how this can be considered cycling.