Metabolic rate simply explained and what happens to it when you are on prolonged diet

Let’s start with a simple energy balance:

And a bit more detailed then:

This is your metabolism broken down into what your energy is used for.

As you are on the weight loss diet, you are eating less than you are using the energy out:

Metabolic rate simply explained and what happens to it when you are on prolonged diet:

This is where your calories in (🍞🍗🍔🍟🍕🍳) are spent for (🚶🧠🤳💩👁👂).

Each of us will have a slightly different metabolic rate, on how exactly those calories are going out, determined by your weight, height, age, gender and other factors ( R. G. McMurray et al 2015)1, however, the divisions will stay pretty much the same:

BMR (basal metabolic rate) – makes up about 60-70% of your metabolic rate and includes lots of chemical processes used by your inner organs like eyes or brain for thinking and reading this article.

NEAT (non-exercise activity thermogenesis) – takes about 30% and is the activity that you do through the day like walking or watching Netflix, this can be higher if you have a physical job.

EAT (exercise activity thermogenesis) – for most of us it’s 10-15% and this includes your gym sessions too. Think it’s so little? Now think again, why you can’t out train the poor diet.

TEF (thermic effect of food) takes 5-10% and is the amount of energy that you use to digest food (E. Trexler et al 2014)2

Now we can talk about the metabolic adaptation.

Your body is not stupid. Your body can adapt to any stress or stimulus that you through at it in order to survive. It actually loves getting fat and being lazy, that’s why it can be so hard to stick to that nutrition/exercise program, right?

Giving him less love & calories for prolonged time will only upset him and he will try and protect the precious fat storage …Because he does not want to die! So you better stay friends with him and ask nicely to get rid of that fat:

About putting extra stress and hatred on your body I will talk in the other blog.

Talking about the different metabolic rates, weight loss effects each of them. The more weight you lose the smaller you get and so you also need less calories for the same bodily processes.

What do you do then?

- Simply readjust your calorie intake 🤷‍♀️

The biggest change in regards of your metabolic rates and being in a calorie deficit is noted in NEAT “NEAT increases with overfeeding and decreases with underfeeding” - Levine JA 2022 (3), without you realising it. You move less around and feel more lethargic:

This can drop by as many as 800kcal!

Result:

Set a target movement like going for a walk or hitting specific number of steps. At the same time, having more calories will increase your NEAT again, so maybe it’s time to rest from that deficit, mh?

Are you stuck in the weight loss cycle with no results? Fill the consultation form found at the bottom of my page ( sunnytrainer.com) and I will get in touch with you soon!