Buzz
The term “calorie” may remind you of nutrition labels and treadmill displays, but in essence, calories are simply a measure of energy. Just as your car needs gasoline, your home needs electricity, and your body requires food for energy. So, how many calories do we burn each day, and how many should we burn? Let’s take a closer look.
The majority of the calories you burn happen even when you're at rest
Calories aren't only expended during exercise. It takes energy to keep your heart pumping, your brain functioning, and your cells repairing themselves, among many other processes.
In reality, most of the calories we burn go toward maintaining our basic functions. Scientists refer to this as our "basal metabolic rate" (BMR). There are various formulas that estimate your BMR, and you can try a calculator like the one at tdeecalculator.net. It uses the Mifflin-St. Jeor equation if you don't know your body fat percentage, and the Katch-McArdle formula if you do.
For example, I entered my own details—I weigh 150 pounds and I'm 5’6”—and the formula estimates that someone of my size burns:
1,352 calories for basic bodily functions (excluding digestion!)
1,623 calories in total if I'm sedentary
2,096 calories in total if I engage in moderate exercise three to five times a week
2,569 calories in total if I'm a dedicated athlete or someone who works out on top of having a physically demanding job
Keep in mind that these numbers are just rough estimates; your actual calorie burn may vary. Several factors influence your total calorie expenditure, including:
Body size: Larger bodies burn more calories both at rest and during exercise.
Muscle mass: Muscle burns more calories than other tissues (which is why having a known body fat percentage gives you a more accurate estimate; less body fat usually means more muscle).
Age: These formulas assume a slight decline in metabolism with age (though some research suggests this may not be significant).
Activity: More physical activity means more calories burned.
Genetics and other unaccounted factors: There is considerable variation from person to person, even among those of similar size, age, etc.
To give you an idea of the range, the Dietary Guidelines for Americans suggest that a 5'10" man weighing 154 pounds will burn a total of between 2,000 and 3,000 calories each day, depending on his age and activity level. In comparison, a 5'4" woman weighing 126 pounds will burn between 1,600 and 2,400 calories daily.
If you think of 2,000 calories as the upper limit for how much to consume—or 1,200 calories as a dieting target—you may be surprised to realize how many calories you’re likely already burning.
How (and why) to burn additional calories
If you're trying to shed pounds, it would seem logical to prioritize diet over exercise. After all, since most of your calorie burn comes from your BMR, exercise only plays a small role in comparison.
However, that’s not the only thing to consider. If your BMR is 1,300 calories and your total calorie burn is 1,600, you could eat 1,300 calories without exercising and likely lose weight. But maintaining health while eating so little is difficult.
Exercise not only helps you burn more calories, but it also provides two significant benefits for your body: it boosts your overall energy expenditure and helps you maintain a healthy lifestyle.
Exercise is universally beneficial for health, no matter how many calories you burn. Aim for at least 150 minutes of cardio each week, combined with strength training to build or preserve muscle.
The more you eat, the easier it is to nourish your body with essential nutrients like vitamins, minerals, fiber, healthy fats, and a variety of vegetables.
A person who burns 2,300 calories and consumes 2,000 is in a much better position to reap the rewards of exercise and healthy nutrition than someone who burns only 1,600 and eats just 1,300.
Want to burn more calories? While you can't turn back time, and gaining weight isn't the goal if you're losing, there are key strategies you can use to increase calorie burn:
Exercise more frequently
Increase muscle mass through strength training and a protein-rich diet
Avoid constant dieting
I've mentioned before how my total calorie burn tends to increase when I eat more food. When you provide your body with adequate fuel, it becomes more inclined to expend energy. This is one reason why it's often suggested to take 'diet breaks' during extended weight-loss phases.
Why relying on calorie burn data from wearable devices or gym machines may not be the best approach.
You might be asking how much exercise is 'enough' to burn more calories. But that's a tricky question: The goal is to transform your habits—shift from being sedentary to consistently exercising—rather than obsessing over the exact number of calories burned in each workout.
Our bodies become more efficient with exercise over time. A 30-minute jog might burn around 300 calories in theory, but in reality, you may only burn, say, 200 more than if you hadn’t jogged. You could feel more fatigued later or find yourself improving in your running and burning fewer calories as a result. (This is still a topic of ongoing research.)
There's evidence that calorie burn estimates from exercise machines are highly inaccurate. Wearable devices like Fitbits and Apple Watches may offer slightly better accuracy, as they account for your exercise intensity, but they're still based on estimates that aren't always reliable.
