One tactic I like to use to stay healthy and keep on track is writing my work outs on a calendar. This way I have a record of what I've done to both be aware if I've slacked off a bit, and also to see what I've accomplished (being proud of your work is great motivation). Personally, I use my iCal, but any calendar, journal, etc. will work. Here is what my month is looking like so far.
As you can see, my second week of August was a little lax (I was on a ranch in the mountains, nearest gym was at least an hour away), but after that I picked it up and did a 4 day work out week.
This isn't something that takes a lot of time to do. Just jot a quick note and move on with your day. This little thing has been a great motivator for me. I love seeing what I've accomplished, and believe me, when you're not feeling like you want to hit the gym, but notice you've only been once in the past week, you will get your butt to the gym.
So, try it out! I don't include my walks with my dog, but you may want to. It's your tracking system, do what you want with it!