Trigger warning: talk about calories and weight loss.
I see you, slogging away at the gym, thinking you’re going to burn a bunch of calories and lose some weight. That’s what we’ve always been told: exercise leads to weight loss.
But how many times have you worked out, and thought that your workout ‘cancelled out’ all the hours you sat that day? I’ve done that, too – when I had a desk job, I’d go for a long walk at lunch, then sat for the rest of the day, thinking that I had exercised, so I was all set.
What I didn’t understand is that exercise is only one key to the puzzle of weight and health.
Exercise is definitely important, and it may have a minor role in weight loss – but the truth about metabolism and the number of calories burned through exercise might shock you.
If you’re spending hours in the gym to lose weight and then spending the rest of the day being inactive, you may want to rethink that, if possible.
Most people don’t exercise at all, because they either can’t, or they dislike doing it. A those who do exercise will often do some sort of activity and then feel justified to be sedentary for the rest of the day, just like I did. Or, they won’t feel justified, but they’ll be forced to sit for 8 hours anyhow, because that’s the nature of our lives these days. We have sitting jobs, we have social media, we have Netflix, and the list goes on.
Only 20% of Americans exercise enough to meet the physical activity guidelines set out by the DHHS. Not only are we not exercising enough, we’re more sedentary than ever.
It’s getting worse, not better.
When people bang on and on about how we’re so much fatter now than we used to be, one of my standard responses is that sure, we may have different eating habits. But our ancestors (even the ones who lived a couple decades ago) walked more because they didn’t have access to cars, public transit, or Uber.
They moved more in general, because modern conveniences like pre-prepared food, TV, and computers weren’t really available. Kids played outside instead of gaming indoors. Adults cooked more, cleaned more (dishwasher? Nope), and maybe took a walk instead of binge-watching the latest shows.
You used to have go to the bank to get money to buy things. Now, you can do everything online, including paying for goods and services.
To understand how this has changed how many calories we burn, and what we can do (besides exercising for hours) about it, keep reading.
Let’s go back to the fundamentals of what makes up our metabolism. In other words, in any given day, how are calories burned by our bodies, and in what amounts.
Your metabolism can be divided up into energy consumed by different systems. The percentages below are average, and of course can vary between people because of genetics, lifestyle, age, gender, etc.
Your BMR, or basal metabolic rate, which is the calories you use to just stay alive, accounts for 70% of calorie expenditure.
That’s way more than half of all the calories your body uses in the day. Those go to lungs breathing, brain thinking, heart beating, liver functioning (the heart and kidneys are huge energy hogs, using around twice the number of calories required for the liver and brain).
Even your fat and bones burn some calories, although very few compared to your other body components.
Thermic effect of food, or TEF, is the calorie expenditure from the digestion of food, and it accounts for around 10% of the calories we burn.
Each macronutrient has a different TEF, fat being the lowest, because it doesn’t require a lot of work and therefore calories to digest. Protein has the highest TEF, because the body needs to do the work of breaking it down into individual amino acids, before it’s absorbed and used.
When someone makes the claim that protein ‘burns fat,’ this is what they’re referring to, because protein has the highest TEF (also: that claim isn’t true – no food or drink burns fat).
Coming in last for energy burn percentage is intentional exercise, or EAT (exercise activity thermogenesis). For the average person, it’s thought to account for only around 5% of the calories we burn in a day. 5%! The average person just doesn’t burn that many calories from exercise, and we often overestimate what we do burn.
this is where NEAT comes in.
But what a lot of us forget about is NEAT, or non-exercise activity thermogenesis. NEAT accounts for calories burned for everything outside of intentional exercise, BMR, and TEF.
The number differs between individuals, but NEAT can account for up to 15% of your calorie burn (some outlets state it as higher – up to 30%).
So, things like cooking, walking to Starbucks to get a coffee, brushing your hair, fidgeting, pacing while you’re on the phone…that sort of stuff. It’s the movement that barely registers on your radar, but it burns calories. Over the course of the day, if you’re you’re moving around a lot, those calories can add up.
Research suggests that people with very active jobs can burn up to 2000 calories in a day just from that. That’s an extreme amount, but most of us can do more to increase our energy usage. This small study also suggests that even during periods of overfeeding, increasing NEAT may be enough to avoid weight gain.
My NEAT definitely went down when I bought a Nespresso. But was it ever worth it.
Measuring NEAT is a bit of a challenge. According to Herman Pontzer PhD, author of BURN (buy it if you haven’t yet, it’s amazing), there’s no direct way to calculate NEAT, so scientists subtract total activity calories from BMR and TEF, then subtract calories burned by intentional exercise. The remaining figure is the NEAT.
James Levine, the scientist who discovered NEAT, did a small study that was published in Science in 2005 where subjects wore what Levine called ‘fidget pants,’ aka underwear with motion-detecting sensors in them.
It was found that those participants who fidgeted the most, burned around 350 extra calories per day over and above those who didn’t fidget as much. Although the study was small, scientists controlled the meals, and was done in 3 11-week phases. It was also found that participants had a ‘biological predisposition’ to either sit, or to get up and pace and fidget.
Assuming that you don’t have hours and hours of time and superhuman endurance (and no, we aren’t talking about athletes in this post), your exercise calories burned won’t likely approach calories expended by NEAT.
Let’s say you burn 300 calories from intentional exercise.
Over the course of the day, if you’re otherwise active, those NEAT calories burned could add up to 350 or more (compared to being sedentary).
I’m not saying that you should stop exercising – exercise is a modifiable risk factor for things such as mood, stress, and overall health. People who exercise regularly have a significant reduction in chronic disease risk.
And while you might think that NEAT doesn’t really amount to much because you aren’t sweating and exerting yourself, that’s not the case. Little movements add up, even if they don’t raise your heart rate.
This 2021 study comparing the fat oxidation level between inactivity and perceived light intensity activity showed that even light intensity activity burned a significant number of calories when compared to inactivity.
There are some possible barriers to increasing your NEAT.
Age, physical ability, mental health, and socioeconomic conditions, for example, can mean that amount of NEAT is decreased. The older we get, the more difficult it can be for us to move freely. People with physical disabilities may be limited in their scope of movement. Mental health conditions can inhibit a person’s desire to be active. And those who work long hours, or live in unsafe neighbourhoods may find it difficult to go outside as much as they’d like.
There’s likely a genetic component in there, too.
Just do your best.
If you’re someone who wants to lose weight (assuming weight loss is appropriate for you (you don’t have a restrictive eating disorder or another condition that weight loss is contraindicated for) and exercises diligently, but hasn’t seen any sort of weight loss, you may be ignoring your NEAT.
It won’t replace regular intentional exercise, but NEAT can definitely help with overall health. And while you can only spend so many hours exercising, most of us can easily increase our movement throughout the day.
If you’re overexercising, or exercising to the point of not wanting to move for the rest of the day, maybe it’s time to take it down a notch.
Dieting and restricting calories may decrease NEAT because of the decrease in energy you may feel from not eating enough. Just one more reason not to go on a diet!
The interesting thing is that out of everything that we see being sold to ‘boost’ metabolism, increasing your NEAT is one way to actually do that.
Keep exercising, but don’t ignore your NEAT!