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Physical Activity Articles
Obesity is an excess of body fat.
It is difficult to directly measure body fat. Body mass index (BMI) is a popular method of defining a healthy weight. BMI should be used as a guide, along with waist size, to help estimate the amount of body fat.
BMI estimates a healthy weight based on your height. Because it considers height as well as weight, it is a more accurate guide than body weight alone.
If you want to keep tabs on your activity level and how many calories you're burning without buying a gadget, check out this government Web site:
It's run by United States Department of Agriculture (USDA). Why is the USDA in the exercise business? Because the department promulgates nutrition guidelines, and good nutrition necessarily involves energy balance, which means making sure that the amount of calories you're taking in should match the number you're burning — and be less if you are trying to lose weight. So although you can't eat physical activity, it's part of the USDA food pyramid.
Recommendations for physical exercise that focus on principles, not numbers.