Philip J. Goscienski, M.D.
Running is a wonderful, exhilarating sport. As an exercise, it's overkill.
Hundreds of thousands of years ago our Stone Age ancestors ran in order to bring down animals for food. Humans became such efficient runners that they could chase after game for hours until the animal slowed down or stopped from exhaustion. Even a deer does not have the endurance of a well-conditioned human.
It may seem like an advantage to live in a land where food is abundant and predators are rare but it's not from a biological perspective. When our ancestors sprinted to avoid being eaten or to capture their next meal they exercised their heart, lungs and blood vessels. We can accomplish nearly as much - and from a practical point of view, all that is necessary - by walking at a brisk pace with less risk of falling, fracture or fatigue. Rarely do walkers tear a knee cartilage, rupture a tendon, crack a foot bone or break an ankle. Those are not uncommon injuries among runners. In other words, unless you are a competitive athlete, running just isn't worth the risk in order to use up a few extra calories.
How about jogging? Doesn't it burn more energy than walking? Not if we compare it with walking at a fairly brisk pace. For instance, if you jogged 5 miles in one hour you would burn 412 calories (average, depending on weight). Brisk walking at 4 miles per hour for 60 minutes would burn 420 calories. The reason is that like running, jogging is a relatively efficient means of locomotion for humans. Walking very fast is not as efficient or smooth, so it takes more effort and it burns up more calories.
The good news: walking at a pace of 3 to 4 miles per hour can melt the fat away if you also make a modest reduction in calories. You can easily walk off about 300 calories a day and cut back on 200 more from baked goods, soft drinks, alcohol, etc. Provided that you are taking in the amount of food that is appropriate for your frame you would lose about one pound every week. By blending exercise with modest diet restriction most of that weight will consist of fat, not muscle. In contrast, severe calorie restriction, whether it's low-carbohydrate, low-fat or low everything will cause you to lose lean body mass - that means muscle and other valuable body parts.
Whether you decide to walk, jog or run, be sure to have a medical check-up if you haven't been exercising in the past year or so. Approximately one-third of Americans over the age of 50 have conditions such as high blood pressure and early diabetes but are totally unaware of it.
Sore muscles are the curse of well-intentioned but overeager exercisers. Don't sabotage your exercise plan by trying to keep up with your well-conditioned buddy. A ten-minute walk is plenty for the first day. Add 5 minutes a day until you reach your target of one hour a day at least 4 days a week. You might even like it so much that you'll take up a new sport - like running.
Philip J. Goscienski, M.D. is the author of Health Secrets of the Stone Age, Better Life Publishers 2005. Contact him at email@example.com.