Step Up Your Walking Workout

Where you walk may be just as important as how long. Experts say walking on grass or gravel actually burns more calories than walking on a flat surface like the mall or pavement. For example, if your track has sand, it's worth going to the park rather than walking one your street as you'll burn about 50% more calories.

One caveat: My trick knee dictates which surface it likes to walk on most often. If you have special considerations like this, be careful. Getting a more intense workout won't pay off if you suffer a re-injury and end up burning no calories because you're out of commission!