"How many calories did that workout burn?" has no single answer — because the burn varies from person to person. But with a simple scientific formula (MET) you can estimate your own number in minutes. This guide covers the calorie burn of popular exercises, personal calculation, and how to turn it into tracking.
The 4 Factors That Determine Calorie Burn
Your body weight, the exercise intensity (MET), the duration, and your fitness level. The most practical way to combine them is the MET formula:[1]
🧮 The formula
Calories burned = MET × weight (kg) × time (hours). Example: a 70 kg person running at 10 km/h (≈10 MET) for 30 minutes → 10 × 70 × 0.5 = 350 kcal.
Popular Activities: Approx. Calories in 30 Minutes (70 kg)
| Activity | MET | ≈ 30 min calories |
|---|
| Walking (5 km/h) | 3.5 | ~120 kcal |
| Brisk walk (6.5 km/h) | 5.0 | ~175 kcal |
| Cycling (moderate) | 7.0 | ~245 kcal |
| Swimming (moderate) | 6.0 | ~210 kcal |
| Running (10 km/h) | 10.0 | ~350 kcal |
| HIIT | 9.0 | ~315 kcal |
| Strength training | 5.0 | ~175 kcal |
Values are approximate; a heavier person burns more in the same activity, a lighter person less. For your own number, plug your weight into the formula.
Post-Exercise Burn (EPOC / Afterburn)
After high-intensity training (HIIT, heavy resistance), your metabolism stays slightly elevated for hours — called EPOC. Useful, but don't overrate it: this extra burn is usually only 6–15% of the workout's calories.
"You Can't Outrun a Bad Diet"
A run that burns 350 kcal can be undone by a single dessert or a large coffee. Exercise is excellent for heart health, muscle and supporting a calorie deficit, but weight loss mainly comes from nutrition (a calorie deficit). The best result is the combination. More: What Is a Calorie Deficit?
See calories burned and eaten in one place
Suu reads your activity from Apple Health and logs meals by voice/photo; it interprets your energy balance in context.
Summary
- Calories burned = MET × weight (kg) × time (hours).
- More weight, intensity and duration means more burn.
- Afterburn is real but small (6–15%).
- For weight loss, exercise + nutrition work together.
Frequently asked questions
What determines how many calories you burn during exercise?
Four main factors: your body weight (heavier burns more), the intensity of the exercise (its MET value), the duration, and your personal efficiency/fitness. The most practical estimate is the MET formula: calories burned = MET × weight (kg) × time (hours). For example, a 70 kg person running at 10 km/h (≈10 MET) for 30 minutes burns 10 × 70 × 0.5 = 350 kcal.
How many calories does 30 minutes of walking burn?
A brisk walk (6–6.5 km/h, ≈5 MET) for a 70 kg person burns about 5 × 70 × 0.5 = 175 kcal in 30 minutes. At a normal pace (≈3.5 MET) it drops to ~120 kcal. Inclines, carrying weight and higher speed all increase the burn.
Do I keep burning calories after exercise (afterburn)?
Yes, some. Thanks to EPOC (excess post-exercise oxygen consumption), your metabolism stays slightly elevated for hours, especially after high-intensity (HIIT, heavy resistance) training. But this extra burn is usually only 6–15% of the workout's calories — don't overrate it.
Can I lose weight with exercise alone?
It's hard. 'You can't outrun a bad diet' is largely true: a run that burns 350 kcal can be undone by a single dessert. Exercise is great for health, muscle and supporting a calorie deficit, but weight loss mainly comes from nutrition (a calorie deficit). The two together work best.
How does Suu use the calories I burn?
Suu reads walking, running, swimming, cycling and 30+ activities via Apple Health (iOS) and Google Health Connect (Android); it automatically raises your daily water goal based on exercise duration and intensity, and interprets your energy balance in context.
Scientific References
- Ainsworth BE, et al. (2011). 2011 Compendium of Physical Activities. Medicine & Science in Sports & Exercise, 43(8), 1575–1581. PubMed: 21681120
- LaForgia J, Withers RT, Gore CJ. (2006). Effects of exercise intensity and duration on the excess post-exercise oxygen consumption. Journal of Sports Sciences, 24(12), 1247–1264. PubMed: 17101527