This tool estimates the rate of fat burning (in grams per minute) based on aerobic capacity and exercise intensity. Understanding your fat oxidation profile helps optimize metabolic health and endurance performance.
Fat Oxidation Rate:
0.85 g/min
Total Fat Burned per Hour:
51 g/hr
Calories from Fat:
7.65 kcal/min
Note: Peak fat oxidation (FatMax) usually occurs at moderate intensities between 45% and 65% of VO2 Max. Beyond this point, the body relies increasingly on carbohydrates.
Fat oxidation is determined by the interplay between oxygen availability and the metabolic demand created by exercise intensity. As workload increases, the body adapts its fuel source based on these physiological parameters.
The fundamental estimation formula is: Fat Oxidation (g/min) = (VO2 Max × Weight × Intensity) × Substrate Coefficient.
Consider a 70kg athlete with a VO2 max of 50 ml/kg/min exercising at a 60% intensity level.
The FatMax zone is the exercise intensity where the highest rate of fat oxidation occurs. For most people, this typically ranges between 45% and 65% of their VO2 max.
Yes, endurance-trained individuals usually have a higher capacity to oxidize fats at higher intensities compared to sedentary individuals due to metabolic adaptations.
As intensity reaches 80-90% of VO2 max, the body shifts primarily to carbohydrate metabolism because it can produce ATP faster than fat oxidation to meet high energy demands.
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