Looking to add an upper body work out to your cardio program? The Powerbelt Walking System ($89.99) is a padded belt that you strap around your waist and use with your arms. The way it works is that you grab the grips and swing your arms, much like you would if your were power walking. The retractable resistance in the cables (connected to the grips) gives you an upper body work out, allowing you to burn more calories.
This is great because you can use the Powerbelt while on the treadmill whereas before it was tough to do any upper body training due to the safety factor. While you may feel a little silly using it, safety is not an issue with the Powerbelt. Buy it on walkerswarehouse.com.