jean-michel, you know your body better than anyone. If you are listening to the ques your body is giving you then much of this can be avoided. In an otherwise normal, healthy person you should be able to take care of these intense loads.

being 41, working 50+ hours a week, having 3 kids and a wife and still getting in 5000 miles a year and racing and working out in the off season, i can definitely say that if you pay attention to the other 90% of your day, then the 10% seems way easier.