22/1/2021 0 Comments
After weight loss, energy consumption can decrease by up to 50%!
In my first blog article, I mentioned what kind of a phenomenon metabolic adaptation is and how to recognize it. Now I will tell you a bit more about what kind of processes are behind the physiological background of the phenomenon.
To understand how metabolic adaptation starts, we need to understand what is included in total energy consumption.
Resting metabolic rate
Resting metabolic rate is the energy consumption that the body requires for maintaining physiological processes - blood circulation, breathing, metabolism in the cell-level, brain activity. It is the amount of energy consumed daily if one lies still in the bed, not eating in a neutral state of mind. Depending on one’s activity level resting metabolism rate is up to 75% of daily energy consumption, which is the most important process that burns calories for a regular person (~1500 kcal/day). The more the person eats and exercises a day, the higher the resting metabolic rate is. In the same way when losing weight, the resting metabolic rate decreases, especially if exercise doesn’t include strength training. This is due to the decrease of muscle mass and that strength training has an increasing effect on resting metabolic rate. Good muscle training increases the resting metabolic rate by 4-10% for a day, which is 60-150 kcal/day (1, 2)
The mere loss of muscle mass doesn’t explain the significant decrease of total energy consumption (8 kcal/kg/day for each fat-free kilograms of body weight, so a 100 kg person who has 30 kg fat in their body = 70 x 8 = 560 kcal/day (3)) which means that the energy consumption of the cell-level decreases.
It happens through:
- slowing down of the activating (sympathetic) autonomic nervous system
- decrease in thyroid hormones
- decrease of leptin
- or decrease in insulin
The biggest problem is that even if the weight rises back after a weight loss, the resting metabolic rate can stay low even for years.
Most traditional weight loss programs do not prevent these changes even if it would be a lot easier than fixing them later on. The biggest mistake dieters make that is that weight loss is mainly caused by a significant decrease in caloric intake. The less one eventually eats, the less they lose weight.
Heating effect of food
The human body can’t use all of the energy it gets from “burning” food. 3% energy from fat, 5-10% energy from carbohydrates and 20-30% energy from protein is transformed into heat. However, the macronutrient composition of a diet does not have a significant effect on total energy consumption, although foods high in protein increase energy consumption slightly.
Home chores are important activities that burn calories
Daily activities are the second biggest source of energy consumption for most of us. This includes all activities that we do daily - job, hobbies, chores, sex, everything but exercise. During weight loss, the body starts to utilize energy more efficiently, so the same amount of activity consumes fewer calories. Another thing is a change in subconscious behaviour - subconsciously we are more passive after a weight loss to conserve energy.
Dieter, take care of your muscle mass!
Since most of us exercise rather moderately, the amount of energy consumption from exercise from total energy consumption is rather small. Physically active people consume relatively small amounts of energy from exercise compared to their daily activities and resting metabolic rate. However, exercise has two important roles in total energy consumption - maintaining muscle mass and increasing the resting metabolic rate. Both will be elaborated more in the next section.
Hence, during metabolic adaptation in our body:
The biggest decrease in total energy consumption comes from the decrease in the resting metabolic rate. It is mostly caused by changes in hormones and the nervous system, but also from the significant decrease in muscle mass.
During metabolic adaptation, the body conserves energy, which means that we consume less energy during daily activities than before losing weight, where the amount and level of activities decrease subconsciously.
The less we eat, the less our body works to digest food.
In the next section, I will tell you what to do to prevent and treat metabolic adaptation.
1. J Appl Physiol (1985). 1993 Oct;75(4):1847-53. Effect of acute resistance exercise on postexercise energy expenditure and resting metabolic rate. Melby C1, Scholl C, Edwards G,
2. Bullough R. Int J Sport Nutr Exerc Metab. 2000 Mar;10(1):71-81. Effect of acute resistance exercise on postexercise oxygen consumption and resting metabolic rate in young women. Osterberg KL1, Melby CL.
3. Long-term persistence of adaptive thermogenesis in subjects who have maintained reduced body weight. Rosenbaum M, Hirsch J, Gallagher DA, Leibel RL Am J Clin Nutr. 2008 Oct; 88(4):906-12.
18/1/2021 0 Comments
Metabolic adaptation is a state where the body's metabolism slows down to a level where losing weight based on caloric intake is constantly becoming more and more difficult, eventually becoming impossible.
“I’ve tried to lose weight but I’m not succeeding. My body must be adapting metabolically.”
If you are one of the many who has been thinking that this is happening to you, this article for you. Everyone who is starting their “weight loss project” needs advice on how to avoid damaging metabolism.
Metabolic adaptation is a fact but also one of the terms that are used way too freely. It is a rare and complex concept.
Metabolic adaptation is a state where the body's metabolism slows down to a level where losing weight based on caloric intake is constantly turning more and more difficult, eventually becoming impossible.
Metabolic disorder also distorts appetite.
Theoretically: if the difference between caloric intake and consumption is - 9000 kcal a week, a person should lose 1kg/2.2lb of weight a week (1 g of fat = 9 kcal). If a 100kg/220lb person reduces caloric intake to 9000 kcal for a week, does it mean that after 100 weeks there is nothing left anymore?
Your body’s main task is to ensure staying alive for as long as possible. It stores energy when it is available and conserves it when it is unavailable. As soon as we eat less than we consume, it sends a message to the body that “energy is scarcely available, so you should conserve it - because we don’t know who long this will last.”. Due to this weight loss is never a linear process. Typically, weight loss looks like this:
As you can see, the longer the energy deficiency lasts the slower the weight decreases. But what does this have to do with metabolic adaptation?
In metabolic adaptation, the metabolism of the body has taken use of long-lasting mechanisms to stay alive with a minimum amount of energy. Our bodies are super smart. They have been created to stay alive as long as possible, not to achieve the body of a fitness model.
Metabolic adaptation is often “diagnosed” very often and easily in situations where weight loss is not achieved. However, 4 out of 5 times it is something completely different.
Metabolic adaptation is common for:
● Yo-yo dieters
● People who have lost weight by eating less without adding exercise
● Women - Women usually avoid muscle mass - apparently for cultural reasons. We will get back to this later.
● People who have lost weight the wrong way - by eating fewer carbohydrates and protein, where the one accelerates metabolism and the other retains muscle mass
● People who have lost weight very quickly
● Some illnesses (hypothyroidism in bad condition, eating disorders, medication that slows metabolism - beta-blockers)
* in the research it was noted that weight loss decreases the energy consumption of the body to 3-4 kcal/kg of fat-free body weight and even if the weight would increase to the same level as before the level of metabolism stays low. For example, after the Biggest Loser Television Series, the weight of the contestants increased by about 41kg/90lbs and the metabolism rate stayed 700 kcal lower than in the beginning! (1, 2)
“But how do I know that I am experiencing metabolic adaptation or something else?”
There is no easy answer to this. Surely the state of metabolism could be accurately assessed using expensive medical research and methods, but if you are not a competitive athlete, these methods are quite unnecessary.
The easiest way to find out how the body consumes energy is to take a 2-week nutrition test.
1. Count every gram of food and drink you have every day. Follow a similar formula for 2 weeks. Exercise just like before - if you did not exercise at all do not add anything, and if you exercised three times a week keep on going the same way.
2. Weigh yourself daily. After 2 weeks you will see a trend - if your weight has stayed the same or decreased. If your weight is the same (not including small normal physiological changes) the situation is clear: consumption = caloric intake. If you have lost weight, do the following calculation:
Lost weight in kg x 7000 kcal (7000 kcal because the body rarely loses weight only from body fat, some of it is also muscle) / 14 + caloric intake.
As a result, you will get an approximate daily energy consumption
For example: you ate 1200 kcal every day for 2 weeks. Eventually, you lost 1.5 kg.
1.5 x 7000 / 14 + 1200 = 1275 kcal
There are also other important factors - such as hormonal balance - but to interpret these factors one must be very skillful and to know the person’s whole history. Rarely a doctor who is unfamiliar with this subject has sufficient know-how in this.
The level of metabolism is individual - metabolic adaptation is an extreme phenomenon of it.
From below what amount of energy does the metabolic adaptation start?
Again, there is no simple answer. This is muchly dependent on the person and the length of energy deficiency (as can be seen from the formula above, the stabilization of energy consumption is not a linear process). The body starts the process of metabolic adaptation already in the first days when the energy balance changes to negative. Roughly it can be said that if you eat 25% less than your daily energy consumption, a significant slowing down of the metabolic rate is in effect (typical to a person who has lost a significant amount of weight. The need for energy that has decreased over 25% is a sign of metabolic adaptation that has progressed quite far, and I have seen quite a few of these kinds of situations also.
Calculate your daily energy consumption: Calorie Counter - Bodyfirst Personal Training (bodyfirstpt.co.uk) NOTE! The calculator is only approximate and easily overestimates consumption!
Other possible symptoms of metabolic adaptation:
● decreased or increased appetite, varying appetite (overeating varies with loss of appetite)
● decreased mood and interest in things
● decreased libido
● tiredness, sleepiness, decreased physical and mental performance
● decreased muscle strength
● slowed down bowel movement
● a decrease in sleep time
● changes or halt in menstrual cycle for women
● slowed down healing of wounds and longer / more frequent infections
● a shift of body fat to the belly/torso
In part 2 I will discuss what is behind metabolic adaptation at a physiological level, and in part 3 I will tell how to avoid and reverse metabolic adaptation. Stay tuned!
Resting metabolic rate: the energy consumption of the body in a totally passive state - if were to lay in bed for the whole day without eating or drinking, in a neutral state of mind
Total energy consumption - all the energy consumed daily - consists of resting metabolic rate, all physical activity, and all elsewhere the body consumes energy
Metabolic adaptation - a term that refers to lowered resting metabolic rate as well as total energy consumption
Kcal - kilocalorie - unit of energy (to warm 1 g of water for 1 °C, 1 kcal of energy is needed). For example, by “burning” 1 g of fat we get 9 kcal of total energy - note: the body can only use a part of it. Some of it is transformed to heat.
1. Leibel R.L., Rosenbaum M., Hirsch J. Changes in energy expenditure resulting from altered body weight. N. Engl. J. Med. 1995;332:621–628.
2. Fothergill E., Guo J., Howard L., Kerns J.C., Knuth N.D., Brychta R., Chen K.Y., Skarulis M.C., Walter M., Walter P.J., et al. Persistent metabolic adaptation 6 years after “The Biggest Loser” competition. Obesity. 2016;24:1612–1619
The covid-19 pandemic has revolutionized how people live and interact with each other. With social distancing being one of the primary guidelines for combating the coronavirus, the year2020 has proved to be isolating. Many companies have embraced working from home and on line to minimize the chances of the virus spreading from one person to another. As a result of the pandemic, social places such as the gym have had to shut down or put in place stringent measures to prevent the spread of Covid-19 among fitness enthusiasts. In a bid to get used to the new normal, new fitness trends have emerged that support digital fitness and home workouts. Below are some of the best fitness trends to be on the lookout for in 2021:
Open Air Fitness Facilities
Limited space has caused several gyms to go out of business since they are unable to achieve social distancing and still make a considerable amount of revenue forthwith. This predicament has since inspired the emergence of open-air fitness facilities. They are perfect for preventing large crowds and ensuring there is social distancing. The facilities are equipped with essential equipment such as air conditioners and heaters that ensure people still achieve body fitness working outdoor regardless of the weather conditions.
Mobile Training Services
In 2021, people are still not in a rush to return to gyms. Covid-19 is still a real threat, and therefore it would be very important for anyone to be even more extra careful as the fight against this pandemic continues. Mobile training services will help bring the gym to the home of any fitness enthusiast. This trend will also help save on purchasing fitness equipment which might be quite expensive considering that you already have a professional personal gym instructor.
Online Fitness Subscriptions
With working from home becoming the new normal, working out at home is increasingly growing popular among fitness devotees. These packages offer a wide variety of services such as dance, gymnastics, yoga, and strength training to keep you fit while at the comfort of your home. The good news is that you do not have to purchase any fitness equipment. All you need is reliable internet connectivity, a fitness subscription of your choice, and get ready to have amazing work out sessions from the comfort of your home.
Online Fitness Experts
Coming up with your workouts can help you keep your body fitness in check while at home. However, with time, your workout programs might become boring. This is why online fitness experts are considered the perfect remedy to provide professional advice, guidance, and
motivation in relation to keeping fit. The professionals will also provide efficient fitness programs so that you enjoy tremendous progress in your journey to keep fit.
Change is very inevitable. This is pretty much evident in the fitness industry putting into consideration the ever-emerging different fitness trends aimed at achieving maximum customer satisfaction. The digital space is proving the best bait in expanding the different ways through which people can be able to exercise. With the inception of online fitness experts, expansion of mobile training services, and the necessity of open-air fitness facilities, it is becoming pretty much easier for people to work out even from the comfort of their residential areas.
New years tend to give us a fresh start. It is at that moment that people come up with new resolutions to lead them for the next twelve months. An individual can decide to change their lifestyle, take up new habits, or choose to pursue a new career at the onset of the year. When it comes to habits, you have to be very careful. If you have laid down some fitness goals you intend to pursue then there are habits that must define you. They include:
I have been weight training, running and cycling for 37 years and I have gained a vast amount of experience in fitness both as a Soldier in The British Army and in the past 21 years having been involved in the fitness industry.