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Looking for the Formula for Losing Weight? It's No Secret.
Tuesday, May 26, 2009
How many calories do you need to cut to lose weight? Begin by estimating the calories you burn in an average day based on your age, sex, height, current weight and activity level. You can do this with the Harris Benedict Equation, developed in 1919.
First, you calculate your basal metabolic rate (BMR), which tells how many calories you burn per day at complete rest.
To calculate BMR for women, use this formula: 655 + (4.35 x weight in pounds ) + (4.7 x height in inches ) - (4.7 x age).
For men, use this formula: 066 + (6.23 x weight in pounds ) + (12.7 x height in inches ) - (6.8 x age).
Next, factor in your daily activity level, using this formula:
Sedentary: BMR x 1.2.
Lightly active (light exercise one to three days a week): BMR x 1.375.
Moderately active (moderate exercise three to five days per week): BMR x 1.55.
Very active (vigorous exercise six to seven days a week): BMR x 1.725.
Extremely active (intense exercise or sports training six to seven days per week): BMR x 1.9.
What the equation doesn't take into consideration is lean muscle mass. Someone with a lot of muscle and little body fat will need more calories, and those with higher body fat will need less. As fitness levels increase, so does BMR.
Nevertheless, Harris Benedict gives a pretty good idea of how many calories you should consume to stay at your current weight. Because a pound of fat equals about 3,500 calories, cutting 500 calories a day will mean one pound lost in a week, a reasonable amount.
But eating less isn't the only way to slim down. To lose 500 calories a day, you also can cut calories by 250 and add a workout that burns 250 calories.
Some tweaking with the formula might be necessary. If weight doesn't drop after a few weeks, cut the calories, increase the exercise, or both. Always hungry? Add calories or back off on the workouts.
Calorie counts for various foods can be found online at sites such as Calorie King (http://www.calorieking.com) and TheCalorieCounter.com. Calories burned via various activities can be found at CaloriesPerHour.com and NutriStrategy.com (http://www.nutristrategy.com).