Tour de France = 23 days, (2 rest days), biggest stress level you can tolerate on a daily basis.
I see many athletes training for Ironman like it's the Tour de France, training hard day after day. The goal in Ironman is to produce a performance on single day, when rested. The Tour de France goal is to produce a performance on many days, when tired. Notice the difference? Your training should reflect this difference as well.
In short, if you're preparing for Ironman, QUIT TRAINING FOR THE TOUR DE FRANCE! It's Ironman, not the Tour.
Coach Vance