Based on my own experience with running, this doesn't surprise me. I've been a runner for about 5 years and am currently running about 40 miles a week. I actu

Based on my own experience with running, this doesn't surprise me. I've been a runner for about 5 years and am currently running about 40 miles a week. I actually find that I'm in better health now (e.g. fewer injuries, better mood, don't get sick) than before I started running. As long as you do are disciplined with your training, your body can adapt to handle the stresses of running: - Increase your mileage gradually. Most experts agree no more than 10% increase per week. - Get adequate nutrition, hydration, sleep. Runners need a little extra calcium and iron than non-runners. Also, you can expect to burn about 100-125 calories per mile, so you want to make sure you are eating enough. - Wear shoes that fit. Your feet actually swell a little bit as you run, so you generally need to buy running shoes that are one size bigger than your normal shoes. Your shoes should feel comfortable - it's ok to be picky and try on a lot of pairs before you find ones you like. Also some people need to buy gel insoles or arch supports to get a better fit. If you're not sure, you can go to a running store and ask for help. - Run with proper form. The way I describe it to new runners is that proper foot strike feels a lot like jumping rope. You want to be light on your feet, hit the ground mid foot and be springy (not stiff) in your legs, and kick back. If you're not sure, try running barefoot somewhere safe like on a grass soccer field - this will force you to run properly. - Allow for some rest days in your schedule, and take a few days off if you find yourself having pain that doesn't go away, or if you have pain that affects your running form. Don't run if you have a chest cold or fever. Be smart and go easy if you have other conditions like asthma or allergies. If you're not sure, see a doctor. Many people now believe that humans are specifically evolved for distance running: http://www.philly.com/philly/health_and_science/20090720_Baring_his_sole.html http://www.philly.com/philly/health_and_science/20090720_Bar...