Let’s compare the benefits of walking to running. Both walking and running will improve cholesterol, lower blood pressure, reduce your risk of Type 2 diabetes, help you lose weight and improve your overall fitness. Unlike bicycling, both are weight bearing exercise, so both will help build bone density.
Walking is definitely easier on your feet, knees and lower back. It is one of the safest exercises and provides the cardiovascular benefits without the stresses of running. But to get the same benefits of running, you have to walk briskly and walk longer — about twice as long. In terms of calories burned, an hour of walking equals a half hour of running.
For maximum health and weight loss benefits, you have to walk “briskly”. Strolling around the block won’t do it. Ideally, you should work up to waking a 15 minute per mile pace, or 4 miles an hour.
To get used to that pace, start on a treadmill. Walk comfortably for a few minutes to get your base line pace; then increase the pace by .5 for as long as you can; rest by going back down to your comfortable pace. When you feel at ease, increase your pace again, etc.