By being alive, that’s how.
It’s the end of an active day.
You are sitting on your couch, watching Homeland and enjoying a glass of wine, and your fitness tracker begins vibrating, congratulating you for hitting your calorie-burn goal.
How is this irony possible? After all, in that moment, you are being sedentary, and in fact consuming calories.
Your body burns a certain number of calories every single day, just by living.
This is why we have to eat – to consume calories – to burn and stay alive. The number of calories you would burn daily, just by being alive and sleeping all day, is your BMR (Basal Metabolic Rate). For example, my BMR when not pregnant is about 1170-1500, depending on the BMR calculator used. I can sleep all day and my body will use 1170-1500 calories to keep me alive.
The scientific formula used to estimate our daily calorie needs is called the Harris Benedict Equation. This equation calculates the number of calories we need to consume every day to maintain our current activity level and weight.
But I don’t want to just be alive, I want to exercise, and walk, and work, and play and have energy. So we need some more calories for that.
If your goal is to maintain your current weight, your daily calorie burn goal could be exactly the same as your BMR. If your goal is to lose weight, your daily calorie burn goal must be greater than your BMR, or you must consume fewer calories than your BMR.
Leaner bodies actually need more calories than less lean bodies.
If you did absolutely nothing and sat on your couch all day, you would still burn your BMR – the number of calories you burn every single day, just by existing. This is why, even if you are not necessarily moving at the moment your fitness tracker reaches its daily calorie goal, you are still burning calories.
Of course, aside from the calorie-burn, there are a million reasons why we should exercise and get up and move – activity is beneficial for our cardiovascular health, cognitive function, fertility, flexibility, mental health, mood, physical strength, and more. So maybe worry a little less about hitting that calorie goal, and focus more on how you feel in your body and moving with activities that bring you joy.