Du bist ein hamburger??

[Mid Life Crisis Marathon Man]

My advice... less is more. 3 sessions a week. No cross training, no massive health kick, just eat sensibly and minimise those known evil foods.

Which is exactly what I did for both my marathons - three runs per week, eat tolerably well and ditch the cross training. Perhaps not ideal if you're after a fast time, but enough to see you through, and most important, far less chance of injury.