Although I've said post 40, these are actually principles you should consider implementing well before 40 years old.
As you approach your 40's you can't train like you did in your 20's (if you did train at all). By adopting the principles discussed in this episode, you will be training smart and lightyears ahead of people your age in terms of training and injury prevention.
For more info on training, go to www.aaronmorton.co