Walking is a very safe sport because it rarely causes injuries. Running causes injuries frequently because you take both feet off the ground at the same time and land with a tremendous force that can tear muscles and shatter bones. On the other hand, when you walk, you always keep at least one foot on the ground and land with minimal foot strike force.

If you want to walk to become fit, you have to move fast. You should exercise vigorously enough to increase your heart rate at least 20 beats a minute higher than when you rest. That means you will be breathing harder and probably perspiring. There are two ways to increase your walking speed. You can take longer steps or you can move your feet at a faster rate. To lengthen your stride, swivel your hips so you reach out further forward with your feet. This will cause you to twist your body from side to side, which will tend to make you point your toes inward when your feet touch the ground. When you point in you lose distance. Try to point your toes forward with each step.

To move your feet at a faster rate, you have to move your arms faster. Every time you move one leg forward, you pull the arm on the same side back and the arm on the other side moves forward. Your legs will only move as fast as you can move your arms. Bend your elbows so you can move your arms faster. The fulcrum of your arm-swing is at your shoulder. The straighter you keep your elbows, the longer it takes your arms to swing forward and back. Bending your elbows shortens the swing and helps you speed up your pace.

Gabe Mirkin, M.D.

Dr. Gabe Mirkin has been a radio talk show host for 25 years and practicing physician for more than 40 years; he is board certified in Sports Medicine and three other specialties.

Dr. Mirkin's daily features on fitness have been heard on CBS Radio News stations since the 1970's. He has written 16 books including The Sportsmedicine Book, the best-selling book on the subject that has been translated into many languages. His latest book is The Healthy Heart Miracle, published by HarperCollins.

Dr. Mirkin is a graduate of Harvard University and Baylor University College of Medicine. A Boston native, Dr. Mirkin did his residency at the Massachusetts General Hospital. He has served as a Teaching Fellow at Johns Hopkins Medical School, Assistant Professor at the University of Maryland, and Associate Clinical Professor in Pediatrics at the Georgetown University School of Medicine. He has run more than forty marathons and is now a serious tandem bicycle rider with his wife, nutritionist Diana Mirkin.