How Many Calories Do You Actually Burn During a Workout?

Calorie burn during exercise depends on four main factors: your body weight, the type of activity, the intensity, and the duration. Heavier individuals burn more calories doing the same exercise because they require more energy to move. High-intensity workouts like HIIT burn significantly more than low-intensity steady-state cardio in the same time window.

Understanding MET Values

This calculator uses MET (Metabolic Equivalent of Task) values — a standard scientific measure of how much energy an activity requires relative to rest. Walking has a MET of around 3.5, jogging around 7, and intense HIIT can reach 10–12. Multiplying your MET by your weight and duration gives a reliable calorie estimate.

Should You Eat Back Burned Calories?

This depends on your goal. If you’re trying to lose weight, don’t eat back all burned calories — use them as a buffer. If you’re maintaining or building muscle, you can replace them, especially with protein-rich foods. Never drop below 1,200 kcal/day for women or 1,500 kcal/day for men regardless of exercise.

FAQ

Why does my fitness tracker show different numbers? Trackers use heart rate and movement sensors which can vary in accuracy. MET-based calculations are more standardized.

Does muscle burn more calories than fat at rest? Yes — 1 kg of muscle burns approximately 13 kcal/day at rest vs. 4.5 kcal/day for fat. This is why building muscle is the best long-term calorie strategy.