What is basal metabolic rate (BMR) ?

THE Basal metabolism , often abbreviated as BMR or basal metabolism, represents the essential amount of energy that your body requires to maintain its vital functions at rest. This includes fundamental processes such as breathing, pumping blood, digestion, and maintaining body temperature .

These energy needs are the incompressible minimums necessary to guarantee the basal functioning of the body, even when you are at rest, fasting for more than 12 hours, and in conditions of thermoneutrality .

Basal metabolism is expressed as calories per day or watts and varies depending on several key factors, including weight, height, sex, muscle mass, and age. These variables explain why basal energy needs differ from person to person.

Different calculation methods for women and men ?

Yes, basal metabolic rate calculation methods take into account differences between women and men. For example, the Harris-Benedict formula , one of the most commonly used methods, provides separate equations for the two sexes.

For men, the formula is: 66 + (6.2 x weight in pounds) + (12.7 x height in inches) – (6.8 x age in years).

For women, it is: 655 + (4.35 x weight in pounds) + (4.7 x height in inches) – (4.7 x age in years).

To understand everything about basal metabolic rate of a woman , read our dedicated article.

These differences in the formulas reflect the physiological variations between the sexes, particularly in terms of body composition and metabolic rate. Men generally tend to have a greater muscle mass than women, which influences their basal metabolism. Understanding these distinctions is essential to accurately calculate basal metabolism and adapt nutritional contributions accordingly.

Basal Metabolism Calculator (Black & al formula)

 

Interpretation of results:

Basal metabolic rate (BMR)	General interpretation*
Less than 1,200 kcal/day	Very low metabolism (often in small, elderly or very sedentary people)
1,200 – 1,500 kcal/day	Metabolism rather low
1,500 – 1,800 kcal/day	Average metabolism (common values ​​in adult women)
1,800 – 2,100 kcal/day	Moderately high metabolism (common values ​​in adult men)
More than 2,100 kcal/day	High metabolism (often in tall, muscular, or young people)

Different formulas for calculating your basal metabolism: which one to choose ?

There are several formulas to calculate the basal metabolism, each having its own benefits And limits . The choice of formula often depends on the profile of the person and the level of precision wish.

Harris and Benedict formula

The Harris-Benedict formula, proposed in the early 20th century, is one of the oldest and best-known for estimating basal metabolic rate. The equations are as follows:

Men: MB = 66 + (13.7 × weight in kg) + (5 × height in cm) – (6.8 × age in years)

Women : MB = 655 + (9.6 × weight in kg) + (1.8 × height in cm) – (4.7 × age in years)

Although still used, this formula is less accurate for certain populations, particularly overweight or elderly people.

Mifflin-St. Jerome Formula

Developed in 1990, the Mifflin-St Jeor formula is widely considered one of the most reliable And scientifically validated . It is recommended for the general population. The equations are as follows:

Men: MB = 10 × weight in kg + (6.25 × height in cm) – (5 × age in years) + 5

Women : MB = 10 × weight in kg + (6.25 × height in cm) – (5 × age in years) – 161

Black et al. formula.

Proposed in 1996, the Black et al. formula offers increased accuracy for specific populations, including overweight or elderly individuals. However, it is more complex to use. The equations are as follows:

Men: MB = 1.083 × weight in kg ^0.48 × size in m ^0.50 × age ^-0.13

Women : MB = 0.963 × weight in kg ^0.48 × size in m ^0.50 × age ^-0.13

In summary, the choice of formula depends on your profile and yours specific needs . The Mifflin-St Jeor formula is generally recommended for the general population , while the Black et al. formula is more appropriate for overweight or elderly people.

Let's calculate your basal metabolism together

For calculate your basal metabolic rate precisely, we use the method of Black et al. , recognized as one of the most reliable. This method is particularly suitable for overweight people and to the elderly people .

Data to be collected (weight, height, age, gender)

To perform the calculation, you need to gather the following information:

• Weight : your weight in kilograms (kg).
• Size : your height in meters (m).
• Age : your age in years.
• Sex : man or woman, because the equations differ according to gender.

Calculation example

Let's say we want to calculate the basal metabolic rate of a 35-year-old man who is 1.75 m tall and weighs 75 kg. Here are the steps:

For men, the Black et al. equation is:

MB = 1.083 × P ^0.48 × T ^0.50 × A ^-0.13

Or :

• P : the weight in kg.
• T : the size in meters.
• HAS : age in years.

By inserting the values:

MB = 1.083 × (75) ^0.48 × (1.75) ^0.50 × (35) ^-0.13

After calculations, we obtain approximately:

MB ≈ 1,918 kcal/day

For a 30-year-old woman, 1.60 m tall and weighing 60 kg, the equation would be:

MB = 0.963 × P ^0.48 × T ^0.50 × A ^-0.13

By inserting the values:

MB = 0.963 × (60) ^0.48 × (1.60) ^0.50 × (30) ^-0.13

After calculations, we obtain approximately:

MB ≈ 1,542 kcal/day

Interpret the result

Basal metabolism is the amount of energy your body needs to maintain its vital functions at rest. For example, if the result for man is about 1,918 kcal/day , this means that his body consumes this energy daily without any physical activity.

This data is essential to adjust your nutritional contributions and define your health goals. It plays a key role in the weight management and the planning your total energy expenditure .

Factors influencing basal metabolism

Basal metabolism calculation formulas provide a useful estimate , but it is essential to understand that the latter can vary considerably depending on several factors. To obtain a more accurate assessment and personalized recommendations , we strongly advise you to consult a health professional or nutritionist.

Here are the main factors that influence basal metabolism:

Age

Age plays a major role in the variation of basal metabolic rate. As we age, basal metabolic rate tends to decrease, mainly due to the loss of muscle mass and increased fat mass.

Generally, older people have a lower basal metabolic rate than younger adults.

Sex

Gender is also a determining factor. Men generally have a higher basal metabolic rate than women, largely due to their greater muscle mass . Muscles, being metabolically active tissues, consume more energy than fats.

Height and Weight

Height and weight directly influence basal metabolic rate. The taller and heavier a person is, the more energy their body requires to maintain its vital functions. However, it is important to distinguish between fat mass and muscle mass, because the muscles consume much more energy than fats.

Body Composition

Body composition, particularly the percentage of fat mass and muscle mass, has a significant impact on basal metabolic rate. Muscles expend approximately 20 to 25% of the basal metabolism at rest, while fat consumes much less energy. Increasing muscle mass can therefore be an effective strategy for stimulate basal metabolism .

Physical Activity

Regular physical activity plays an essential role in maintaining and even increasing basal metabolism. In particular, prolonged exercise causes an increase in muscle catabolism, which stimulates basal metabolism during the recovery phase.

In addition, practicing physical activity helps to prevent muscle catabolism often associated with restrictive diets. This is a valuable ally for maintaining optimal muscle mass.

Genetic and Environmental Factors

Basal metabolism is also influenced by genetic factors And environmental factors , such as climate or lifestyle. For example, a lack of sleep can slow down your metabolism , while extreme weather conditions can increase your energy expenditure to maintain an adequate body temperature.

By taking these things into account, you can better understand why your basal metabolic rate may vary from someone else's, even if you use the same calculation formulas.

Let's move from basal metabolism to total energy expenditure

Calculate your basal metabolism is an essential step, but to better understand your overall energy needs, it is equally important to consider your level of physical activity . This will allow you to determine your daily energy expenditure (DEJ) .

Understanding the concept of physical activity level (PAL)

THE physical activity level (PAL) is a key element for estimating the total energy expenditure . It represents the intensity and duration of your daily physical activities.

NAP is usually expressed as a physical activity factor, which varies depending on the type and intensity of activities performed. For example, a sedentary person will have a low NAP, while a professional athlete will have a high NAP.

Here are the most common NAP categories:

• Sedentary : Little or no physical activity.
• Slightly active : Light physical activity (1 to 3 days per week).
• Moderately active : Moderate physical activity (3 to 5 days per week).
• Very active : Intense physical activity (6 to 7 days per week).
• Extremely active : Very intense physical activity (more than 7 days per week) or heavy physical work.

Calculate your daily energy expenditure (DEJ)

To determine your Daily energy expenditure : To calculate your basal metabolism, you need to add the energy consumed during your physical activities. Here are the steps to follow:

1. Calculation of basal metabolism : Use one of the formulas mentioned above to get your basal metabolic rate.
2. Determination of NAP : Assess your level of physical activity and assign it an appropriate multiplication factor.
3. Calculation of energy expenditure related to physical activity : Use the METs ( Metabolic Equivalent of Task ) method to estimate the energy expended during each activity.

The formula used is as follows:

Energy expenditure (kcal) = MET × weight (kg) × duration (hours)

For example, for a 1-hour weight training session with a MET of 6 for a 75 kg man:

6 METs × 75 kg × 1 hour = 450 kcal

4. Calculation of the DEJ : Multiply your basal metabolic rate by the NAP factor, then add the estimated energy expenditure for each physical activity.

The final formula is:

DEJ = MB × NBP + Energy expenditure due to physical activity

This method offers a more precise approach to tailoring your nutritional planning to your specific needs , especially if you engage in regular or intensive physical activities.

How to boost your basal metabolism naturally ?

Boost your basal metabolism in a natural way is not only possible, but also beneficial for your overall health . Discover proven ways to boost your metabolism without resorting to chemicals or questionable supplements.

Adapted Diet and Nutritional Rebalancing

Diet plays an important role in boosting metabolism. Here are some dietary guidelines to follow:

• Lean Protein : Include lean proteins like chicken, fish, eggs, beans, and legumes in all your meals. Protein requires more energy to metabolize than carbohydrates or fats, which contributes to increase basal metabolism .
• Complex Carbohydrates : Choose complex carbohydrates rich in fiber such as sweet potatoes, brown rice, spelt, or oats. These foods require more energy to digest, thus activating the metabolism.
• Good Lipids : Consume healthy fats found in avocados, oily fish, nuts, and oils like sesame and sunflower. These fats are essential for optimal body function and promote metabolism.

Hydration and Meal Frequency

Proper hydration and proper meal frequency are also important:

• Hydration : Drink at least 1 liter of water per day, mainly between meals. Proper hydration can increase basal metabolic rate by 3% while improving digestion and nutrient absorption.
• Meal Frequency : Eat 5 small meals each day instead of 2 or 3. This strategy helps maintain an active metabolism throughout the day.

Targeted Physical Activity

Physical activity is a powerful accelerator of metabolism:

• Bodybuilding Strength training is particularly effective because muscle uses more energy than fat. Even short sessions of 15 to 20 minutes a day can help burn calories while you're at rest and boost your metabolism.
• Cardio HIIT : High-intensity interval training (HIIT) cardio activities are also very effective at increasing metabolism. These sessions can increase metabolism by more than 40% for 72 hours after exercise.
• Regular Activities Regular physical activities such as walking, jogging or cycling also help to increase energy expenditure and maintain an active metabolism.

Sleep and Stress Management

Sleep and stress management are essential for optimal metabolism:

• Sleep : Quality sleep is essential for the body to regenerate and maintain an active metabolism. Lack of sleep can slow down metabolism.

[MY] Women's Balance Essentials specifically helps improve sleep through a targeted composition of relaxing herbs, adaptogens and vitamins.

 

• Stress Management Stress management is important because chronic stress can negatively affect metabolism. Practicing relaxation activities like meditation or yoga can help reduce stress and maintain a healthy metabolism.

[MY] Serenity Essentials contributes to stress management through a thoughtful synergy of 3 adaptogenic plants, 3 highly bioavailable forms of magnesium, and vitamins B + D.

By integrating these natural methods in your daily routine, you can significantly boost your basal metabolism and improve your overall health.

What you need to know about calculating basal metabolism

Understanding and calculating your basal metabolism constitutes an essential step for optimal management of your health and weight. The formulas of Harris-Benedict , Mifflin-St Jeor , and Black & al. are valuable tools that help estimate your basic energy needs. To get an accurate estimate, it is important to consider factors such as age , sex , the size , the weight And body composition .

By adopting a balanced diet, rich in proteins , complex carbohydrates And good lipids , while practicing regular physical activity, you can significantly improve your basal metabolism. Managing the stress and the sleep also plays a key role in this process. Remember to take into account your physical activity level to calculate your daily energy expenditure and adjust your nutritional intake accordingly.

It's time to take action ! Calculate your basal metabolic rate, adopt healthy habits, and consult a health professional to benefit from personalized advice. A more balanced life and better health are within reach.

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FAQ

What factors influence an individual's basal metabolism ?

THE basal metabolism of an individual is influenced by several factors, including age, height, weight, sex, as well as genetic factors and body composition, especially the amount of muscle. Climate and facultative thermogenesis can also play an important role.

How does basal metabolism differ between men and women ?

Basal metabolic rate differs between men and women in several key ways:

• Women burn more carbohydrates and less fat at rest compared to men.
• Men generally have a higher body mass , which results in a higher basal metabolic rate, requiring more calories for their basic functioning.
• Sex hormones, particularly estrogen, influence women's ability to burn calories and store fat.

What proportion of daily energy expenditure is basal metabolism ?

The basal metabolism represents between 60% and 70% of daily energy expenditure. This proportion varies depending on the individual's level of physical activity, ranging from 45% for very active people to up to 70% for sedentary individuals.

Why is knowing your basal metabolic rate important for weight management and overall health ?

Knowing your basal metabolism is essential for weight management and overall health. This indicates the minimum amount of energy needed for the body to function at rest. By understanding this energy requirement, it is possible to adapt calorie intake and physical activity to:

• Optimize calorie burning.
• Prevent loss of muscle mass.
• Maintain a healthy energy balance.

A precise understanding allows for the implementation of personalized strategies in terms of diet and exercise, thus promoting sustainable weight loss and better overall health.