Walking and Weight Loss
Walking can provide a moderate cardio workout and burn significant calories, provided you move quickly enough. For optimal results, walk at least 3.5 mph, a brisk pace, which burns about 273 calories per hour for a 150-pound person. You'll get even better results at a very brisk 4.5 mph, which burns about 307 calories per hour at the same weight. To burn even more calories, alternate a few minutes of walking with 30 to 60 seconds of jogging or running. For perspective, you must burn 3,500 more calories than you eat to shed 1 pound.
Following Centers for Disease Control and Prevention guidelines, most people should get 150 to 300 minutes per week of cardio exercise. Walking at a rate of 4 mph, it would take you 150 minutes to cover 10 miles -- so you'd meet your weekly minimum in just one day. Multiply that times seven days per week, and you're looking at 1,050 minutes per week, more than triple the upper recommendation. For healthier -- and more realistic -- weight loss, walk for an hour a day, five days per week, which totals 300 weekly minutes.
Dangers of Overexercise
Walking 10 miles per day can easily lead to overtraining, which occurs when you push too hard and don't allow ample recovery time. With excessive walking, you may experience sore or injured muscles, bone injuries, headaches, trouble sleeping, high morning heart rate and a weakened immune system. According to the American Council on Exercise, you may also begin to feel depressed and irritable, and lose your self-esteem and motivation.
Successful Weight Loss
Don't be in too much of a hurry to slim down -- successful weight loss doesn't come from pushing exercise limits, but rather by establishing healthy habits that you can keep for life. Weight loss begins with your diet, so avoid fast food and processed snacks and instead cook whole, natural foods at home. Portion sizes also matter; a serving of cooked pasta or rice is just half a cup, while a serving of protein is about 4 ounces. Increase fruit and vegetable intake, and avoid extra calories from beverages such as cola or creamy coffee drinks.