Why Does Apple Fitness Show “Total Calories” and “Active Calories”
When you track activity on your Apple Watch and then go to the Fitness app to view your data, it will often give two different answers to the question “How many calories did I burn?” These are active calories and total calories . You may notice that sometimes both fields show the same number, and sometimes two different numbers appear.
Difference between “Active Calories” and “Total Calories” in Fitness App
You’re probably familiar with the idea that exercise burns calories. We could say, for example, that a half-hour run burns 300 calories. (The exact number will depend on factors such as your height and running speed, but let’s use this as an example.)
So jogging burns calories, but you would still burn some calories if you stayed home and watched TV, but not as much. Remember that it takes a lot of calories to keep your body alive and functioning.
For example, if you weigh 200 pounds, you’ll burn about 46 calories in half an hour of watching TV. (Yes, there is data on this .) Meanwhile, half an hour of running at an easy pace burns 363 calories. This means you burned a total of 363 calories, but only 317 of them exceed what you would burn if you stayed at home .
That’s what Apple is trying to convey with its “active” and “total” calorie labels. Let me give you an example from real life. I once went for an easy three-mile run that took about 38 minutes. Apple reports that I burned 351 calories, of which 294 were active. (This means it thinks I would have burned 57 calories if I hadn’t been running at the time.)
How do we burn calories that are not active calories?
It takes a lot of energy to keep the human body alive! You need your heart to beat, your lungs to breathe, and your brain to think. Every cell in your body has to perform a variety of microscopic maintenance jobs to stay alive.
This may seem like a terrible sight, but think about how a dead body differs from a living one. It ceases to protect itself from germs and fungi and begins to fall apart. The reason this doesn’t happen while you’re alive is because your body is constantly working hard to repair damage, attack invaders, etc. And all of this requires energy, which we measure as calories.
I discussed this a little more in this article on how many calories we burn every day . Let’s give a few examples. A 200-pound, 6-foot-tall man is expected to burn 1,930 calories per day as his basal metabolic rate; a 150-pound, 5-foot-5 woman would burn 1,426. That’s not even counting any exercise or even daily activities like walking around the house and brushing her teeth.
This number, which represents the minimum required for survival, is called the basal metabolic rate or BMR. Closely related is the resting metabolic rate, or RMR, which includes the energy we use to digest food. RMR plus our activities, such as exercise, equals the total number of calories burned in a day.
If you’re interested in knowing your RMR, the Apple Health app includes a resting energy metric that estimates your RMR. However, take this number with a grain of salt. It’s calculated based on your age, gender and weight, so it’s just a rough estimate of how much someone your size can burn.
Why are active and total calories sometimes the same?
I’m seeing different active and total calorie numbers for activities that I’ve recorded directly in the Apple Watch fitness app. You know the one – it’s a greenish-yellow icon with a little running man.
But my active and total calories are the same for workouts logged through other apps. Strength training from Whoop? 58 active calories, 58 total. Five mile run with Strava? 695 active, total 695. My morning walk, picked up by Oura? 68 active, 68 total.
This is not because my basal metabolism has stopped firing, but simply because these apps only report one calorie burn number to Apple. Since the Apple Fitness app doesn’t know the division, it simply reports the same number in both places.
Which number should I focus on: active calories or total calories?
Tricky question! Calorie burn measured by wearable devices ( any wearable device, not just the Apple Watch) is not always reliable . Therefore, the most correct answer is: neither one nor the other.
But if you find it useful to track your calorie burn with a wearable device, perhaps to keep track of how much more you should eat if it’s been a high activity day, active calories will be most useful. Going back to the example of my three-mile run, that run burned 294 more calories than I would have burned if I hadn’t gone for that run. So if I wanted to eat enough to offset the extra burn, I would eat the active amount of 294 calories rather than the total amount of 351.