Our metabolism is a pretty nifty thing! While it's way to complex to measure with just a tape and a scale, we can predict just enough about our body's composition to take a peek inside the inner workings of our metabolisms.
40 kg
88 lb
Length from feet to top of head
120 cm
47 in
Thinnest horizontal measurement above the belly button
50 cm
20 in
Widest horizontal measurement about the stomach
50 cm
20 in
Widest horizontal measurement about the groin
70 cm
28 in
*If you're transsexual, please pick whichever you are transitioning into.
Adipose tissue predictions are derived from a simple 3-site equation developed by the United States Army, based on a study of active United States Soldiers.
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1.8 kg
Resting metabolism can be accurately predicted with a power-law (the Pontzer equation #5), or semi-accurately predicted directly (the Cunningham equation). Both are shown here for completeness.
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Resting metabolism can be accurately predicted with a power-law (the Pontzer equation #5), or semi-accurately predicted directly (the Cunningham equation). Both are shown here for completeness.
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Our metabolism has two distinct, but very important tasks: maintaining our tissue and homeostasis (such as keeping our body warm), and providing enough energy for us to move and go about our daily tasks. The amount of energy expended during both tasks is correlated, but it's also not 1:1.
Our body can be split into fat-free mass and fat mass, each of which generally consumes about the same amount of maintenance energy per kilogram. Thus, despite being double integration, we can expect an 80% margin of error in the ballpark of 250 calories, which I think is a pretty good estimate for most people.
Beyond that, activity expenditure is kind of a mystery. I'd like to find some kind of validated model that works off of daily steps but I haven't found one yet. Until then, i've just provided the recommended static physical activity levels (PALs) of 1.2, 1.6, and 2.1.
I hope this tool is useful for you! Please let me know if you have any questions, comments, or concerns by e-mailing me at [email protected].
Herman Pontzer et al., Daily energy expenditure through the human life course. Science 373, 808-812 (2021). https://doi.org/10.1126/science.abe5017
Prado-Nóvoa, O., Howard, K. R., Laskaridou, E., Reid, G. R., Zorrilla-Revilla, G., Marinik, E. L., Davy, B. M., Speakman, J. R., & Davy, K. P. (2024). Validation of predictive equations to estimate resting metabolic rate of females and males across different activity levels. American Journal of Human Biology, 36(4), e24005. https://doi.org/10.1002/ajhb.24005
Taylor KM, Castellani MP, Bartlett PM, Oliver TE, McClung HL. Development and cross-validation of a circumference-based predictive equation to estimate body fat in an active population. Obes Sci Pract. 2024;e747. https://doi.org/10.1002/osp4.747