An item missing from stage setting is how many miles do you normally do per week vs the tour distance?

Shootingstar has a good point, "everyone is dffierent". I'm 10 years your junior, but I ride at about the same speed as you. I normally do about 150-ish miles/week. After a ride that covers twice my distance, I'd reward myself with a week of taking it easy -- walks if I felt like it and shorter, flat distances (don't push yourself--ride at an effort that feels like a casual stroll).

I'd not be surprised to feel sluggish for a week or so after that--more if I pushed it really hard. Studies show that the rest phase is more important the older we get--easy days after every hard effort and an easy week ever 3-4.

You'll see gain from your effort if you make sure to give your body rest. Not necessarily a day -- just a day at lighter effort.

http://www.drmirkin.com/fitness/8844.html