Everywhere is walking distance if you have the time.
— Steven Wright

The Commitment - An average of two high intensity workouts per week. An average of two long walks per week.

At roughly the same time that I started reducing the amount of gluten in my diet, I started working out with a trainer in a way that was very new and different for me.  He was a certified trainer in the Crossfit method, which emphasizes "constantly varied, high intensity, functional movement[s]."  Said another way, crossfit-style workouts pack a lot of difficult movements and exercises (often with very heavy weights) into a short period of time.  I was used to hour long runs or bike rides and was amazed at the results I saw from 10-20 minute workouts. Its an addicting way of working out, gets you in great shape, and takes very little time each week.  I have never done the program, but P-90X is also a popular method of high intensity training. Other options could be sprints (running, biking, swimming) or interval training.

Walking is something that I have always loved, and don't do nearly enough.  Walking is very low impact, easy for anyone to do, and makes us much healthier.  Another perk is that walking so often leads to interesting new thoughts and ideas.