Knowing how much energy your body uses each day is essential for achieving your goals (weight loss, muscle gain, maintenance, etc.). These energy needs depend on two fundamental elements: your Basal Metabolic Rate (BMR) and your Physical Activity Level (PAL) . In this article, we'll explore these concepts in detail and show you how to estimate your needs using our calculator. Ready to discover what your body expends each day? Let's go!

Basal Metabolic Rate (BMR): What is it?

Basal Metabolic Rate (BMR) refers to the amount of energy our body uses at rest to maintain its vital functions. This includes processes such as breathing, heartbeat, and body temperature regulation. In other words, BMR represents the energy required for our body to function without any physical activity.

MB is influenced by several factors:

• Age : Metabolism generally slows down with age, mainly due to the decrease in muscle mass.
• Sex : Men tend to have a higher BMR than women due to a greater proportion of muscle, which burns more energy than fat.
• Body composition : People with greater muscle mass have a higher BMR, because muscle consumes more energy at rest.
• Genetic factors : Some people naturally have a faster or slower metabolism than others.

Physical Activity Level (PAL): understanding its influence

Physical Activity Level (PAL) , as its name suggests, refers to the intensity and frequency of your daily physical activity. It is essential to consider your PAL when estimating your total energy needs. Indeed, your BMR alone is insufficient to determine your daily energy expenditure, as it does not account for physical activity. The PAL score is therefore calculated by multiplying your BMR by a specific value.

Here are the different categories of NAP:

• Seated job, little physical activity : This level applies to people who spend most of the day sitting, with little or no movement. For example, an office job with little physical movement. The NAP factor here varies between 1.3 and 1.4.
• Sitting jobs, short trips, moderate physical activity : People with office jobs who move around regularly during the day (e.g., short trips in town or moderate walking) may have a NAP of 1.5.
• Strenuous work or regular and rather intense physical activity : If you do work that requires more physical effort (e.g. manual jobs or regular sports), your NAP will be between 1.6 and 1.7.
• Intense and regular physical activity : Athletes or people who regularly engage in intense physical activity (e.g., frequent training, high-level sports) will have a NAP that varies between 1.8 and 2.

Estimate your energy needs

The theoretical formula is a simple method for estimating your daily energy needs based on your BMR and NAP. While this formula provides a general idea, it remains approximate, as each individual is unique and several other factors can influence your actual needs.

The theoretical formula

• For women: MB = 9,740 × Weight (kg) + 172.9 × Size (m) − 4.737 × Age​ + 667.051
• For men: MB = 13,707 × Weight (kg) + 492.3 × Size (m) − 6.673 × Age​ + 77.607

Next, to obtain your total energy requirements, you must multiply your BMR by your Physical Activity Level (PAL). Note that this formula does not work for a teenager.

If you would like an easier estimate, use our energy needs calculator . It will allow you to quickly calculate your total energy requirements.

Achieve your goals

If your goal is to gain muscle mass, it's essential to consume more calories than your body burns daily. This involves a nutrient-rich diet, but other techniques are also possible. For example, there are specific supplements available for muscle gain.