It’s well established that exercise provides a good way to burn calories and lose weight. But exercising alone doesn’t guarantee that you’ll drop any pounds. To lose weight you must create a calorie deficit by burning more calories than you ingest. If you wish to slim down, take a look at your diet and lifestyle first, then create an exercise program to help you achieve your goals.
Things You'll Need
 Calorie scale

Determine your basal metabolic rate (BMR), which estimates the number of calories your body burns per day, without taking your activity into consideration. For women, start at 655. Add your weight in pounds times 4.35, then add your height in inches times 4.7. Subtract 4.7 times your age in years from the previous subtotal, to determine your BMR. A man begins with 66, then adds 6.23 times his weight, plus 12.7 times his height, before subtracting 6.8 times his age. For example, a 30yearold woman who’s 5 feet 4 inches tall and weighs 130 pounds would calculate as follows: 655 + (4.35 x 130) + (4.7 x 64) – (4.7 x 30). This results in a BMR of 1,380.3 calories burned per day.

Factor in your activity level, using the Harris Benedict Equation, to estimate your daily energy expenditure. If you’re sedentary, multiply your BMR by 1.2 to estimate how many calories your body burns in a typical day. If you do some light exercise one to three days per week, multiply your BMR by 1.375. If you perform moderate exercise three to five times days per week, multiply by 1.55. If you exercise vigorously six or seven days each week, multiply by 1.725. If you perform very intense exercise daily, multiply by 1.9. Remember that a physical job counts as exercise.

Calculate the number of calories you’re currently ingesting. Use a calorie scale to determine the number of calories in everything you eat. Add up the numbers each day for a week, then divide the total by seven to determine the average number of calories you ingest each day.

Subtract the number of calories you burn each day from the number of calories you’re ingesting. If the result is a negative number, you already have a calorie deficit. If the number is positive, you’re taking in excess calories.

Choose your exercises so you’ll burn off sufficient calories to create a calorie deficit. For example, if your daily caloric intake is 2,000 and you’re burning 1,800 calories per day, perform exercises to burn more than 200 calories each day. You have countless choices when selecting your exercise program. If you’re new to exercise, you can begin by walking. If you weigh 155 pounds, walking at just 4 mph  that’s one mile every 15 minutes  burns 167 calories every 30 minutes. At 155 pounds you can also burn 223 calories in 30 minutes by swimming, 167 with moderate calisthenics, 260 with lowimpact aerobics or 112 by lifting weights.
Tips & Warnings
 All else being equal, the more you weigh, the more calories you’ll burn during exercise.
 You can estimate the number of calories you burn daily using a variety of online calculators, if you don’t wish to do the math yourself. Try several calculators and use the average result, because each site will likely deliver a different number.
 You can also create a calorie deficit by reducing the number of calories you ingest, or by combining exercise with a lowercalorie diet.
 See your doctor before you start a new exercise program or make major changes to your diet, particularly if you’ve been inactive or if you have any health concerns.
References
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