Energy Balance Equation PDF

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this content explains how energy input and energy output relate...

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Energy Balance Equation Energy balance is simply the relationship between your energy input and your energy output. The complete energy equation looks like this: Energy Input (calories in) – Energy Output (calories out) = Energy Balance It doesn't look very complicated. But you may not have the numbers to do the math. So to figure out your energy balance you need to gather some important information. Calculate Energy Balance To learn how to manage your energy balance, you need to gather numbers related to your energy input and energy output. Energy Input We input energy when we eat. The food we consume provides calories. Calories are simply a unit of energy or heat. The food we eat and the drinks we consume provide different amounts of energy. Protein and carbohydrates each provide 4 calories per gram, and fat provides 9 calories per gram.1 So how do you know your energy input number? Count the number of calories you eat each day. You can do it with a simple downloadable food diary or you can use a popular calorie counting app. An average woman may consume anywhere from 1,600 to 2,400 calories per day.2 That's a pretty big range. To get the most accurate number for you, track your calories for at least a week. Energy Output Energy output happens when your body uses energy. We often refer to this as "burning" calories. Even when you’re sleeping, your body uses energy to perform basic functions like breathing and circulating blood. The rate at which your body burns calories at rest is called your basal metabolic rate (BMR). BMR makes up roughly 60% to 75% of the total number of calories you burn each day.3 You also expend energy during activities of daily living, like washing dishes or shopping, and of course, through physical exercise. These activities make up about 15% to 30% of your total calorie burn each day.4 The last 5% to 10% of calories (give or take) are burned through the thermic effect of food when you eat and digest meals and snacks.5 There are different ways to calculate the number of calories you burn each day. One of the simplest ways is to use a calorie calculator.

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Energy Balance and Weight To determine how your energy balance will affect your weight, you need to determine if you have a positive or negative balance. To do so, take your numbers and input them into the equation at the top of the article. Then find out if you have a negative energy balance or a positive energy balance. If your energy input and your energy output are more or less balanced, you will maintain your current weight. A perfect energy balance creates a stable weight. To change your weight you need to tip the scales so that they are no longer balanced. Positive Energy Balance A positive energy balance occurs when your energy input is greater than your energy output. That is, you eat more calories than your body uses. Your body stores excess energy or calories as fat. This results in weight gain.6 Energy Input > Energy Output = Weight Gain Negative Energy Balance Weight loss occurs when you create a negative energy balance. That is, you burn more calories than you consume. When this imbalance occurs, your body burns stored energy (fat) in order to function and you lose weight.7 A negative energy balance is sometimes called a calorie deficit. Energy Input < Energy Output = Weight Loss When you evaluate your own energy balance, it's best to get the numbers as accurate as possible. Even small differences in energy input and energy output can make a big difference in your weight.

What is a BMR calculator? Your Basal Metabolic Rate (BMR) is equivalent to the amount of energy (in the form of calories) that your body needs to function if it were to rest for 24 hours.

How can you calculate your BMR? Calculating your basal metabolic rate is easy; all you need to measure is your weight and height, although your age and sex also come into play. The calculators for both sexes are as follows: 2

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For men: BMR = 10 x weight (kg) + 6.25 x height (cm) – 5 x age (years) + 5

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For women: BMR = 10 x weight (kg) + 6.25 x height (cm) – 5 x age (years) – 161

What is the Harris-Benedict equation? The Harris Benedict Equation is a formula that uses your BMR and then applies an activity factor to determine your total daily energy expenditure (calories).

How to determine the Harris-Benedict equation? To determine your total daily calorie needs, multiply your BMR by the appropriate activity factor, as follows: 

Sedentary (little or no exercise) : Calorie-Calculation = BMR x 1.2

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Lightly active (light exercise/sports 1-3 days/week) : Calorie-Calculation = BMR x 1.375

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Moderately active (moderate exercise/sports 3-5 days/week) : CalorieCalculation = BMR x 1.55

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Very active (hard exercise/sports 6-7 days a week) : Calorie-Calculation = BMR x 1.725

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If you are extra active (very hard exercise/sports & a physical job) : CalorieCalculation = BMR x 1.9

For more on BMR, check out the Mifflin St Jeor equation and the KatchMcArdle formula Keeping a healthy diet and using the Harris-Benedict calculator to keep an eye on your BMR will make it easier for you to stay in good health. Thanks to the Harris-Benedict calculator and Harris-Benedict equation you can know the perfect amount of calories to eat if you want to keep your body weight as it is. If you are looking to gain or lose weight, you can also use this number as a point to eat more or less then, respectively. Please remember to consult a medical expert if you are looking to gain or lose a lot of weight.

FAQ 3

How do I calculate my BMR? To calculate your BMR, you would usually use the Harris-Benedict equation: 1. For women, it's BMR = 10 ⨉ weight (kg) + 6.25 ⨉ height (cm) – 5 ⨉ age (years) – 161 . 2. For men, the formula is BMR = 10 ⨉ weight (kg) + 6.25 ⨉ height (cm) – 5 ⨉ age (years) + 5.

What is BMR? Your Basal Metabolic Rate (BMR) is equivalent to the amount of energy, in calories, that your body needs to function if it were to rest for 24 hours. What does BMR mean? BMR stands for basal metabolic rate. It is the minimum number of calories that your body needs for basal functions like breathing, digesting, and keeping the body temperature steady over a day.

What is a good BMR? The average BMR is about 1409kcal (5900kJ) for a woman and about 1696kcal (7100kJ) for a man.

How do I increase my BMR? To increase your BMR (basal metabolic rate), you can try: 1. Eating more protein in every meal. 2. Doing more HIIT (high-intensity interval training) workouts. 3. Increasing your daily activity - choose stairs over the elevator, walk more, switch to a standing desk. 4. Eating more spicy foods. 5. Doing more resistance workouts - muscles burn more calories than fat tissue.

Calculating the Harris–Benedict BMR[edit] The original Harris–Benedict equations published in 1918 and 1919.[1][2]

Sex

Units

Calculation

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Metric

BMR = 66.5 + ( 13.75 × weight in kg ) + ( 5.003 × height in cm ) – ( 6.755 × age in years )

Imperia l

BMR = 66 + ( 6.2 × weight in pounds ) + ( 12.7 × height in inches ) – ( 6.76 × age in years )

Metric

BMR = 655 + ( 9.563 × weight in kg ) + ( 1.850 × height in cm ) – ( 4.676 × age in years )

Imperia l

BMR = 655 + ( 4.35 × weight in pounds ) + ( 4.7 × height in inches ) - ( 4.7 × age in years )

Men

Women

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