Total Daily Energy Expenditure (TDEE) calculators and exercise applications should be used only as theoretical starting estimates, as they often overestimate actual energy expenditure.

noli's read

This perspective is strongly supported by research on activity tracking technologies. A major validation study from Stanford University (Shcherbina et al., 2017), published in the Journal of Personalized Medicine, evaluated several popular wearable devices and found that, while heart rate was measured well, no device accurately estimated energy expenditure, with error margins of 27% to 93%. Furthermore, a systematic review of the scientific literature confirms that these consumer technologies struggle to provide reliable measurements of calories burned. Work from Harvard University (2026) also highlights that the algorithms in these devices are based on approximations and often display error rates of 30% to 80%. The idea that these tools provide an absolute truth for calibrating one's nutrition is therefore scientifically contradicted. Using these figures as a simple theoretical benchmark, to be adjusted subsequently based on one's own physical observations, remains the most rational approach.

the sources

1. 1Hall KD, Heymsfield SB, Kemnitz JW, et al. 2012
2. 2Rolls BJ 2009
3. 3thefitness.wiki