In addition to building and maintaining lean muscle , one of the main goals of fitness you need to aspire to as you age is cardiovascular health and endurance . As we see more pages of the calendar peel off into the wind, far too many of us begin to slow down and exercise less, which leads to weight gain, a slower metabolism, and an increased risk of metabolic disorders. If you're 60 or older, you need to be doing aerobic exercise to stay active, burn calories, and to maintain heart health. Some of my favorite forms of cardio are long walks, jumping rope, cycling, and rowing. However, a tool that I like to use for cardio is the treadmill. The problem is, when using the treadmill, most people make the mistake of going at a low intensity and incline level. The body can—and will—adapt to any cardio workout you put it through, and it will be more efficient as you repeat the same workout. After all, if you burned 100 calories in one session, the next few times you do it you might be b