Home Nutrition How to Calculate BMR - Basal Metabolic Rate? Formula attached

How to Calculate BMR – Basal Metabolic Rate? Formula attached

The main principle of achieving progress in sports is one single factor that will be considered in the following material – basal metabolic rate — 40% workout, 20% sleep, and 40% nutrition. However, the question is how to plan nutrition to attain specific goals correctly? Of course, the plan takes into account physical and mental needs and expenses.

What Is BMR?

Basal metabolic rate (or basal metabolism) is an indicator of energy and the intensity of metabolism in the human body. It is determined by the amount of fasting energy in optimal temperature conditions, which is necessary to maintain the homeostasis in complete physical and mental rest.

Simply put, basal metabolism shows how much energy the body spends to maintain the constant activity of internal organs, muscles, and the central neural system’s work.

The energy that the body receives as a result of such reactions goes to ensuring a constant body temperature.

Thanks to basal metabolism, the following features are provided:

  • basic hormones synthesis;
  • basic enzymes synthesis
  • basic cognitive function provision;
  • food digestion;
  • normal sleep;
  • immune system maintenance;
  • anabolism and catabolism balance maintenance;
  • respiratory functions maintenance;
  • main energy elements transportation by blood;
  • constant body temperature maintenance.

This is not a complete list of what is happening in our bodies. Even when a person is sleeping, most of the processes, albeit slower, help to synthesize new building elements and carry out the breakdown of glycogen into glucose. All this requires a constant influx of calories that a person receives from food. In particular, this necessary consumption is the daily minimum of how many calories are needed to maintain the body’s basic functions.

basal metabolic rate

Rubner’s Body Surface Law

Oddly enough, but sometimes the metabolism is determined not only by biochemical processes but also by simple laws of physics.

The scientist Max Rubner revealed a relationship linking the total surface of the body with the number of calories burned.

How does it work? Two main factors made his assumption correct:

  1. Body size. The larger the body’s surface, the larger the organs, and the greater the need for energy that puts the entire system in motion.
  2. Maintaining heat. For the normal functioning of the body, metabolic processes occur with the release of heat. For humans, the average temperature is 36.6 degrees Celsius. Moreover, the temperature (with rare exceptions) is evenly distributed throughout the body. So, to heat a large area, you need more energy. All this is connected with thermodynamics.

Therefore, from all lead us to the conclusion:

«Bulky »people really spend more energy during their basal metabolism. Tall people are most often thin due to calorie deficiency caused by increased basal metabolism and spending of energy necessary to maintain temperature for a larger body area.

Factors Responsible For Basal Metabolic Rate

The initial basal metabolic rate in men with a body weight of about 70 kg averages 1700 kcal. For women, such parameters are 10% less.

If we consider the level of basal metabolism as a dynamic system, then some factors determine the basic background, and the amount of energy distributed:

  • The amount of incoming energy. The more frivolously a person forms their diet (a constant excess of calories, frequent snacking, intentional acceleration of metabolism), the more actively the body spends energy even in a passive mode. All this leads to a constant increase in the hormonal background, in the load on the body, and, as a result, more rapid failure of individual systems.
  • The presence of artificial stimulants of metabolic rate. For example, people who use caffeine have a lower basal metabolism if they quit using it. At the same time, their hormonal system begins to malfunction.
  • General mobility of a person. During sleep, the body transports glucose from the liver to muscles, synthesizes new amino acid chains and enzymes. The amount of resources spent on these processes directly depends on the total load on the body.
  • Change in basal metabolic rate. If a person takes himself out of balance, then the body will spend additional energy on the restoration and stabilization of all processes. Moreover, this applies to both acceleration and deceleration.
  • The presence of external factors. Changes in temperature will cause the skin to intensely release heat to maintain overall temperature, which can change the dynamic factor that affects the whole level of basal metabolism.
  • The ratio of digestible and excreted nutrients. With a constant excess of calories, the body can simply reject unnecessary nutrients. In this case, basal spending will increase for the process of converting useful nutrients for the means of transportation only.

Besides, it is worth highlighting the main end products of metabolism, which are, regardless of its rate, are excreted from the body.

Related Articles


Please enter your comment!
Please enter your name here

Related Articles

Ecdysterone – Increases Your Muscle Mass? Uses, Side Effects, Dosage

Ecdysterone is a natural substance with hormone-like properties that controls molting and metamorphosis in arthropods in bodybuilding. There is...

Soy Protein and Muscle Gain Good or Bad?

Soy has recently become one of the most popular protein products with soy protein, consisting of isoflavones and saponins, being the most...

4 Different Ways To Increase Metabolism & Burn Calories

Increase Metabolism - Main Myth: fast metabolism always leads to a lean and skinny build, while a slow one leads to putting...