The Problem (and Solution)
Everyone knows that we experience chronic aches and pains in parkour. It is inevitable, right? Some would even say it's a good part of the learning process.
I've found, through my experiences with training myself and others and through reading (Dr. Phil Maffetone and Thomas Kurz mostly), that it is not necessarily an inevitable part of training.
They describe the problem, in short, as having a severely undeveloped aerobic energy system.
The solution, for those who are experiencing regular interruptions to their training due to injury, is to build the aerobic energy system using really low intensity aerobic activity by monitoring using a heart rate monitor to stay in your aerobic range.
Unfortunately, parkour is almost entirely anaerobic (high intensity, short duration) and this type of training easily leads to over-training from not allowing enough recovery. Anaerobic training takes more recovery if the aerobic system is not well developed.
The Solution Isn't Practical!
Ideally, we would get beginners to spend 3 to 6 months building their aerobic base before gradually introducing them into the higher intensity parkour. Also, those who intend to train regularly for years to come will need to build an artificial "season" or seasons into their year. A couple of months each year should be devoted to building the aerobic base to avoid aches and pains. This would detract from the appeal to beginners so it doesn't seem very practical.
So, I've been learning about this in more detail lately. The results from case studies seem undeniable and I am going to embark upon an "off" season to build my aerobic base. I realise that this doesn't fit in with parkour as we know it so I'm happy to be the guinea pig and report back how the experiment goes. Maybe, if the results are good enough, others might try it too. The best motivation comes from great results.
Your Part
I'm really interested to hear from the sport-scientists and the cross-fitters among you on these issues. I seem to have some injury, even minor ones, come up every year. It's enough that I'm sick of the interruption to my routine and I want to solve it. It may not be much of an issue for the young uns though...
Over the last few years I've found that reducing the amount of work per session and having more sessions is a better way to train as recovery is better, but there is a barrier still and I think I need to reduce the intensity even more to be totally aerobic for a time.
There are a lot of factors, like how I intend to carry this out, but that will come in further discussion or you can have a read here and here or here on my blog
That was then, this is now: Having spend 6 months building my aerobic base, I have lost very little parkour strength and skill. My immunity is much better, my recovery is insanely better (combined with fish-oil high in EPA), and I have higher energy combined with lower stress. Well worth the experiment!