When I was in the Marines, I was running several miles a day and I could walk all day long without even breaking a sweat. I remember how great I felt all those years ago and I never thought I'd let myself get out of shape again.
For years, I had thought about getting back into a walking or jogging program again but I always rationalized against it by saying I didn't have the time. Well it all started in early March when on a balmy day, I decided to go for a walk at lunch instead of getting yet another sausage and meatball sub. During that walk, I realized that I could get in 3-4 miles every day with no loss of productive time. It felt so good walking again that I decided to get up an hour earlier (5AM) and walk three miles BEFORE work as well. So now I get 6 miles a day and none of this cuts into my personal time. When I go home after work, I still have the entire evening to do what I wish (except I have to go to bed an hour earlier which is no big deal).
Once I reach my target weight, I'll probably give up the 5AM walks but I'll still do the lunchtime ones to maintain. So during this time of getting up at 5AM, I consider myself "back in boot camp."
But at age 40, enough is enough. I'm back in "boot camp."