In the past, I've been so worried about losing fitness that I didn't give myself enough recovery time after running a marathon- I just wanted to get right back to pounding out miles and nailing workouts so I could improve on my fitness and keep working toward faster and faster times, but that is a sure way to go down the road to injury.
This time around, I decided to take it easy for 2 full weeks- just enjoy the time off, enjoy not waking up at 4:45am, enjoy not having sore and tired legs, and let my body get a good rest so it will be ready for the next round of training. Other than an easy paced 40 mins on trails with a friend last weekend, I haven't run a step, and my body is thanking me for it. I feel well rested, and I have no aches or pains, so it's time to think about getting back into the training.
I plan on easing into it slowly- there's no rush, and I want to make sure that I don't wake up any lingering injuries that might be lying dormant after my marathon. This coming week I plan on a few easy paced runs, but no hard workouts. Next weekend I'm pace bunnying a local marathon (I'm the 4:15 bunny), so that will be a good, long run, but at a very relaxed pace. I think the week after that I'll start to build some workouts back in- there are a few trails races this fall that I want to do, and I need to sharpen up on speed and hills.
If you're running a fall marathon this year, don't feel compelled to jump right back in to your training. It's much better to take a couple of weeks off to recover now than a couple of months off later on to recover from injuries.