Energy Balance- How does the body use up the food we eat?
In today’s article, we are going to discuss the different categories that make up our total daily energy expenditure (TDEE). These are basal metabolic rate (BMR), Resting metabolic rate (RMR), Thermic effect of food (TEF), Exercise activity, and Non-exercise activity thermogenesis (NEAT). I’ll also lend my thoughts on how we can use this information to approach fat loss more intelligently.
Basal Metabolic Rate (BMR)
BMR refers to the minimum number of calories our body needs to maintain its regular function while at rest! BMR is measured by having someone fast and lay very still so that scientists can calculate BMR. This doesn’t involve digesting food.
BMR makes up 70% of total daily energy expenditure, meaning for someone who eats 2000 calories per day, 1400 of those calories are used to keep us alive! It takes a lot of work to keep the human body alive.
Resting Metabolic Rate (RMR)
RMR is similar to BMR. However, it is easier to figure out since conditions don’t have to be as extreme as BMR (e.g., you don’t have to lay still or fast). RMR is measured similarly as BMR. RMR is slightly higher, due to environmental factors, movement and digestion, but only by around 10% of BMR.
Thermic Effect of Food (TEF)
Digesting, absorbing and assimilating foods we eat is an active process, meaning it takes energy to do so. Eating increases our metabolism! How much our metabolism increases depends on what we eat. For example, eating plenty of protein- meats, protein powder and eggs etc., will increase our metabolism as protein takes the most energy to digest and metabolise. Fat, on the other hand, tend to have the lowest thermic response.
TEF usually accounts for 10% of our total daily energy expenditure. The number may change depending on factors such as insulin resistance, which can lower TEF.
Exercise Activity (EA)
EA is planned or purposeful exercise. For example, going to the gym or running outdoors. EA varies greatly depending on the individual. Generally, more sedentary people might have 10-15% of their total energy expenditure from exercise.
For more physically active individuals, energy burnt through exercise can be as high as 30% or more.
Non-Exercise Activity Thermogenesis (NEAT)
NEAT is any other activity we do during the day that isn’t intentional – walking to work, cleaning the house, playing with our kids or pets, and carrying groceries. For individuals who have a sedentary job (desk job), NEAT does not contribute much towards their daily energy expenditure.
NEAT is an essential contributor to energy balance as it can vary a lot depending on the individual.
Total Daily Energy Expenditure (TDEE) Chart
The char below is an average breakdown of TDEE. BMR/RMR will more or less stay consistent. The other three, TEF, EA and NEAT, will vary by around 5-10% depending on the individual.
What does this mean for me if I’m trying to lose body fat?
The point I want to emphasise is that performing physical activity is not a good way to create an energy deficit so we can lose fat. Sure, it helps, but there are other, more efficient ways to do so. I think the reason most people want to create the deficit through exercise is:
1) The more food we eat, the more energy we have. More energy may encourage us to move more.
2) It’s “easier” to exercise than it is to focus on the most critical factor- eating.
3) Most people approach their eating wrong when trying to lose fat. They focus on the wrong things- supplements, finding “the best” diet strategy out there whether it be keto, fasting etc. They look for “easy”, short term fixes instead of focussing on the bigger picture; creating consistent eating habits and training regularly.
Creating and being consistent with eating habits and training regularly, over months and years, not days and weeks, is the best approach for most people to use to have long-lasting fat loss.
What can I do now to start creating these habits?
The best things for you to do now is to walk (around 10,000 steps per day) and drink water (2-3L) per day. That’s it. Walking is a powerful tool in helping us get fit, healthy and lose body fat.
Drinking water is a no brainer. Most people are de-hydrated. Like I tell most people, anything but alcohol and coffee counts as fluids/liquids. The best thing for us is good ol’ water.
That’s it. Master those two essential habits, for at least 2-3 weeks then move on to other habits. What could these other habits be? I generally recommend my clients think of the easiest thing they can achieve and do that. For one person that may be incorporating resistance training 1-2 a week, eating four servings of fruits and so on. For more help with this, you can always just send me an email- firstname.lastname@example.org.
That’s it for now. Stay well, train, eat, and sleep hard!