In my view, one of the greatest things about Parkour is that you can incorporate pretty much any movement into your style. With no competition there are no rules. We're not fussy about this; there have already been a wide selection of breakdance, gymnastic, strength training and general dance movements added to our repertoires. They say that necessity is the mother of invention, but Mum's nowhere to be seen here.
As parkour has evolved, so have training methods. Today you see a lot more people supplementing their parkour training with weight lifting than you did just two or three years ago. There's obviously nothing wrong with this. Many people (including me) have seen great strength and performance gains as a result of incorporating weight lifting into their parkour strength training. However, as this trend continues, I've seen many people completely reject the high repetition endurance training that parkour was built on.
Over the past 8-weeks, I have been teaching a course at UCLA. There are two sessions per week, 1.5hr each. The course is the first of its kind in America (as far as I am aware). It mainly takes place in doors at UCLA’s large gymnastic gym; however, we have had the opportunity to head outside for three of the classes. The students have excelled and shown surprising steps in the 8-week period.