Staying fit when you're busy

This month is December, and being the typical mailman, I'm getting a lot of overtime. We have over the past months been doing 30 percent of Amazon's volume, but recently that has climbed to 70 percent. The overtime is great on the wallet, but with time, it gets to the point where it wears one out. Then add to that my personal circumstances of working out after work are now trashed, due to family responsibilities at home, and you can see that my regimen has been trashed.
I've given a lot of thought as to what I might do to counteract this annual trashing of the routine. My first thought is, to not worry about it. The body needs some time to recover from hard workouts and maybe I just need to decide that December is that time. I can begin again with renewed vigor in January.
Then again the gym rat in me says "no". There's got to be another way. I thought about basketball players in the NBA. In the off-season, the dedicated ones do a lot of strength training to build themselves up for the season. Then, during the season, they can't work out as much as they'd like, but they are doing other things to keep in shape. In their case it's playing basketball. So, I ask, how can I emulate that while delivering mail, mostly from a truck?
One way is to decide that the trips up to people's houses with packages is my workout for the day. I can run, to increase the intensity of my workout, or I can walk, to keep from tripping or for an easier workout. With hundreds of packages each day, this kind of working out can add up. I may not get the intense focus on various areas of the body to strengthen, but my general fitness can remain high. And I can tone it down in a limited way by walking instead of running.
So, think of your own personal circumstances and do the best with what you have.
Another to consider is diet. This time of year it's easy to grab treats that your loving friends and neighbors have dropped by. It's much easier to grab a cookie than to make a sandwich, for example. But this is the time to keep on top of your eating habits and limit yourself. I like to choose certain days to overindulge--my family's Christmas party is one of them--and then limit myself the rest of the time. Don't keep totally away from Aunt Mildred's fudge, but limit yourself to one small piece. That way, you keep a certain amount of control. Eating habits are even more important than exercise in the way we feel and in maintaining a healthy weight.
And then, when you set your goals for the New Year, you will have already created within yourself the discipline you need to advance those goals past the first month and throughout the rest of the year.