Tips to help you reach your exercise and weight loss goals

Published: August, 2012

Need to lose weight? Cutting back on calories consumed while bumping up total activity level is the most effective method.

Wolfing down a candy bar takes a mere minute or two; walking off those calories would take most people about 40 minutes. To lose a single pound, you need to burn approximately 3,500 calories. Doing so through activity alone could easily take a few weeks of regular, moderate exercise. On the other hand, consuming 500 fewer calories a day will result in the loss of a pound a week. For that reason, dieting alone seems as though it would be a fast path to weight loss.

But regular exercise offers certain benefits beyond calorie burning. It slightly increases your resting energy expenditure— that is, the rate at which you burn calories even when the workout is over and you are at rest. And pounds lost through boosting your activity level consist almost entirely of fat. Plus, some studies suggest exercise preferentially targets abdominal fat, which plays a role in hypertension, cardiovascular disease, and diabetes.

Counting calories: What it takes to burn a pound of fat

It takes roughly 3,500 additional calories spent in physical activity to burn a pound of fat.
Walking or jogging uses up roughly 100 calories per mile. (Note: Your actual calorie expenditure depends on a number of factors, including your weight and pace.)
You'll shed approximately a pound of fat for every 35 miles you walk, assuming your levels of food intake and other physical activity remain the same.
If you walk briskly (at a pace of 4 mph) for half an hour on five out of seven days, you'll log 10 miles a week. At the end of three-and-a-half weeks, it's possible to lose 1 pound even if the number of calories you consume stays the same.
If you also cut back on the amount of food you eat by a few hundred calories a day, you can hasten the pace of your weight loss.

For easy exercises that will achieve results, purchase Exercise – A Program You Can Live With from Harvard Medical School.

How vigorously should I exercise?

Whether you are healthy or have medical issues, moderate activity is safe for most people and does plenty to improve your health. If you're in good shape, adding vigorous activities to your workouts cuts time spent exercising and is a boon to health. If you're not fit, work up to vigorous activities slowly. Higher-intensity activities raise your chances for muscle or joint injury and very slightly increase the odds of developing a serious heart problem. This applies particularly to people who are unaccustomed to physical activity, who suddenly start exercising vigorously (although the overall risk of dying from heart disease is lower than if you did no exercise).

How can you judge the pace of your workout? The easiest way to measure exertion characterizes the intensity of an activity through broad categories, such as light, moderate, or vigorous. Called perceived exertion, it's especially helpful for staying in a safe range of activity. As you improve your fitness, you'll find your perception of the intensity of a particular activity—walking up a nearby hill, for example—changes.

The table below describes physical changes at each level of exertion. If you're just getting started with an exercise program, aim for a moderate pace. (If health problems or disabilities make moderate activity impossible, simply do as much as you can.) As you build up, try a mix of moderate and vigorous activities to help build endurance. As you work out more often, you'll notice gains as exercises become easier. Whenever an activity becomes easy, boost the length of your workout or your intensity again.

How hard are you working?
Light Easy
Breathing easily
Warming up, but not yet sweating
Able to talk—or even sing an aria, if you have the talent
Light to moderate You're working, but not too hard
Breathing easily
Sweating lightly
Still finding it easy to talk or sing
Moderate You're working
Breathing faster
Starting to sweat more
Able to talk, not able to sing
Moderate to vigorous You're really working
Huffing and puffing
Able to talk in short sentences, but concentrating more on exercise than conversation
Vigorous You're working very hard, almost out of gas
Breathing hard
Finding talking difficult

For additional information on this and other questions about starting a healthy exercise program, purchase the Special Health Report, Exercise, A Program You Can Live With from Harvard Medical School.

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