Total Daily Energy Expenditure (TDEE)

Everyone should know “their number,” or at least have a general idea of what it is. If you haven’t quite guessed as to what I am referring to based off the title, I am referring to your total daily energy expenditure. Going on throughout life without knowing this number or basically how many calories your body uses in a day puts you at a huge disadvantage. That number alone can equip you with enough knowledge to navigate your fitness goals. Knowing this number should be just as important as knowing your phone number, your social security, or your address. After all, it is unique to you and only you.

Throughout our lives, we put so much energy towards learning all these details about everything else but our own bodies. But it is only through learning about how our body works that we will be successful towards our pursuit of health and fitness. In this post I’ll be describing what our TDEE is exactly, why it is important, and how it affects us. This will include discussing our basal metabolic rate, or what many of us refer to as our “metabolism,” and briefly talk about our non-metabolic uses of energy beyond exercise that many of us often forget about. So, let’s get on to answering what is likely your first question.

What is TDEE?

Our Total Daily Energy Expenditure (TDEE) is basically the total amount of calories we use in a day. It includes what our body needs at our baseline (aka basal) along with any additional energy used to do anything from lifting weights, to something as simple as fidgeting your fingers. 70% of your body’s total energy goes towards your basal metabolic rate (BMR). Much of this is out of our control…at least directly. However, there are great ways to actually alter the BMR to our benefit that we will discuss later on. The 30% of your TDEE is what is affected more directly by what you do day to day. It is broken down into exercise activity thermogenesis (EAT), Thermic effect of food (TEF), and Non-exercise activity thermogenesis (NEAT). These three components make up the non-resting energy expenditure (NREE). Whereas the BMR represents the resting energy expenditure (REE). This is all depicted in the chart below to help visualize and clarify.

https://www.researchgate.net/figure/Components-of-total-daily-energy-expenditure-TDEEBMRbasal-metabolic-rate_fig1_260397860

What is our Basal Metabolic Rate?

If you had the chance to read my post about the first law of thermodynamics you might already have an idea of what our BMR is. If not, i’ll briefly go over it here along with a more in-depth post on how to calculate it all in a subsequent post specifically about BMR. This number is a critical component to your daily expenditure. After all, as you saw above it is responsible for roughly 70% of all your calories used in a day. That 70% of your daily expenditure plainly speaking, is the number of calories required to maintain all basic life sustaining processes within the human body. This is the energy required to “keep the lights on,” within our bodies. You might think most of your calories burned come from exercise and your daily activities, but you’d be wrong.

Many people when attempting to lose weight will hop right on the treadmill to burn the calories, however, you’ll be on that treadmill for hours in order to make a reasonable impact. This poses the question though, if 70% of my calories burned come from my BMR then why am I told to exercise so much? Well, exercise has significant benefits beyond that of the numbers you’re seeing. But also the type of exercise you do it even more important. I am by no means saying cardio is not important, it is critical for our cardiovascular system. What I am saying is that there are exercise plans that will in fact increase your BMR and thus allow you to burn more calories at baseline. This will give you the benefits of burning calories directly from exercise along with obtaining the indirect calorie burning benefits from the BMR.

Your BMR will follow you throughout your entire life. It will change and for most people it continues to slow down as we age. The only way to halt this is by taking steps towards increasing this number as it is the largest player in your TDEE. The most researched-backed method involves a plan that increases muscle synthesis/mass. Think about it this way. If I told you that your BMR is the energy that keeps the lights on in your house, then what would happen if we increased the number of lights you use, or the overall size of the house? You’d use more electricity right? Similarly, if you increase your size either through mass via fat, or mass via muscle your BMR will effectively increase as well! This is why weight comes off so quickly the heavier you are. Your BMR is actually higher to maintain that size. However, most people would prefer to have more muscle mass than fat mass. At least I assume you do if you are here reading about how to optimize your health.

Non-Exercise Activity Thermogenesis (NEAT)

We often forget that quite literally every single motion, breath, and activity actually takes up energy. It makes up anywhere from 10-15% of our daily energy expenditure but it can have a significant impact. Especially for the people whose jobs require more walking, movement, or other repetitive tasks. This is also one of the reasons why simply getting more steps in throughout the day can actually have a profound impact over time. Perhaps you decide that you’ll take more walks throughout the day at work, take the stairs, or even park further away from your destination. Think of it this way, even if that adds up to something as small as 100 calories a day, every month you would have used an additional 3000 calories. In one year this is about 10 lbs by simply including just a little more movement into your day, whatever it may be. I understand that this might not be your one stop solution. However, remember that the purpose of this website is to equip you with fundamental concepts to apply and set-up a general framework throughout life. 

Thermic Effect of Food (TEF)

Whenever you begin to eat or consume a lot of food do you begin to feel hot and/or sweaty? This occurs for most people and this is known to be the thermogenic effect from food. You’re experiencing your body ramping up the processes necessary to break down your food into its final biochemical form. However, what you’re feeling is only scratching the surface of what is happening. When we eat, we are consuming food but they are ultimately broken down from macromolecules to micro molecules. The classic three macromolecules that we should all be aware of are proteins, fats, and everyone’s favorite carbohydrates.

The macromolecules eventually get broken down to the most basic units, absorbed, and eventually used or stores. There are two things I want you to know about macros. The first thing is that each type of macromolecule has a separate pathway of breakdown, and each pathway requires a certain amount of energy. For now, I’ll leave you with the information that protein requires the most energy, and fat requires the least amount of energy. The second thing I want you to remember is the macro split you are consuming will factor into how your body is composed. What I mean by macro split is what percent of carbs, fats, and protein your calories are coming from in a day. For example, someone with a diet plan with a set number of calories a day may be composed of 35% protein, 40% carbohydrates, and 25% fats.

I wrote a post that takes all of this information into greater depth along with a discussion of the relevant research studies. If you have no interest in that then at the bare minimum try this. If you have a plate of food in front of you, remove 1/3 of the carbs, and replace that with a protein. Just like that you will consume less carbs that are not getting used, and increase protein consumption which will then increase your thermogenesis resulting in more calories burned. Studies have shown with confidence that having a more protein-forward diet will increase fat loss, and increase muscle synthesis. This will directly contribute towards the recomposition of the human body overtime.

Exercise Activity Thermogenesis (EAT)

As you may have seen above, this part is responsible for only about 10% of your TDEE. Remember that this is based off the average person, and it does not mean that this has the lowest impact. If you look at it solely as a numbers game then there will be days you will be disappointed. This is not going to remain as motivating for individuals. However, what I want you to take to heart is that the indirect benefits from this are immense. As I have mentioned, when doing the correct exercises and workout regimen you will generate a greater BMR, increased NEAT, as well as a TEF from a diet more tailored to this lifestyle.

Beyond the numbers alone, this part of your calorie expenditure will be your investment into your health where consistent exercise of just 2-3 days a week will lead to immense reduction of risk towards 30+ chronic disease’. Focus on this as your motivation and less on the numbers. As you remain consistent everything else will follow along with it. This is what I would call “dividend investing” in the fitness world. It requires some work up front, but you will be paid dividends upon dividends of calorie burning activity, along with a better quality of life. There is a lot to go over in this section alone, so expect additional posts going into detail on everything you should and will need to know to feel confident about how your body works, while simultaneously creating a plan to help support it.