A daily walk on the treadmill can help you get the amount of moderate-intensity cardiovascular activity recommended by the National Institutes of Health. However, if you choose walking to lose weight, the frequency, duration and intensity of your workouts matter. A half-hour of brisk walking almost every day helps you lose weight — but the more time you spend on the treadmill, the faster you'll see results. Consult your doctor before beginning any new exercise or diet regimen.
Your Walking Program
The treadmill might be the best piece of exercise equipment for you if you enjoy walking or running. Treadmills, which can be set to various speeds and inclines, can also efficiently track how long you've walked at any given speed and the distance you travel. Walking on the treadmill is also a weight-bearing exercise, which may reduce your risk of osteoporosis later in life. The number of calories you burn depends on your weight, intensity and the time you spend on the treadmill. According to the American Council on Exercise's online physical activity calorie calculator, someone who weighs 140 pounds burns only 64 calories for every 30 minutes she walks on the treadmill at 2 miles per hour — a very casual pace. A brisk 3.5-mph walk of the same duration burns 121 calories. Someone who weighs 180 lbs., however, would burn 82 and 155 calories, respectively, during the same timed workouts.
Increasing Your Efforts
Harvard Medical School points out that the number of calories you burn is the ultimate determinant of how rapidly you lose weight and gain health benefits from your walking program. If you've just joined a gym or purchased a treadmill and haven't exercised in a long time, the American Council on Exercise suggests easing into your walking program. Start with five- to 10-minute walks, increasing your duration and intensity by 10 to 20 percent every week. Strive for at least 30 to 40 minutes of brisk treadmill walking practically every day of the week. Harvard defines the minimum amount of cardiovascular activity recommended by groups such as the American College of Sports Medicine and American Heart Association as an "excellent starting point" for reducing your risk of heart attack, stroke and an early death — but, if you want to lose weight, 60 minutes of exercise each day is the best way to burn extra calories.
Target Heart Rate
The intensity of your walk — the amount of effort you put into your treadmill workouts — matters when it comes to weight loss. You'll burn some calories at an easy plod; however, the American Council on Exercise recommends that the intensity of your walk increases your heart rate to at least 55 but no more than 90 percent of its maximum. Your maximum heart rate, measured in beats per minute, is 220 minus your current age. For example, if you're a 40-year-old adult, your maximum heart rate is roughly 180 bpm. Therefore, the target rate you should aim for is anywhere between 99 and 162 bpm. To determine if your pace is brisk enough, take a brief pause during your treadmill workout and press your fingers lightly against the carotid artery on the side of your neck. Count your pulse for 10 seconds, then multiply it by six.
Walking on a treadmill can get you the weight-loss results you want. But because weight loss is ultimately about the numbers, it's important to take into consideration the number of calories you consume every day and keep in mind that your exercise program doesn't give you carte blanche to eat at will. If you burn 500 calories more than you consume each day through a reduced-calorie diet and exercise, you'll lose roughly 1 lb. of weight a week. According to the Centers for Disease Control and Prevention, a healthy weight loss is slow and steady -- between 1 and 2 lbs. per week.