My first century of this season was two months ago. Since then, I have ceased with the long distances and mostly have just walked for minimal exercise. It's time to break out of chairlandia and go for a short run in the morning, three times a week. This starts in less than 12 hours when I, without thinking, get my ass out of bed and put on my shoes for 20 minutes.
When you get stuck in a chair or on a couch, just admit that the flab is starting to take hold and peal yourself away from the monotony. Restart with something easy and incredibly consistent.