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RC_ITR

But it could be a more complex formula.

For example, the max 'healthy' weight for a 6'10" person is 230lbs.

That's more or less Kevin Durant's draft stats and he looked like this:

https://twitter.com/si_vault/status/749993324195479553

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For sure, but most people are not 6'10. For 95%+ of the population it works fine.

Just to be clear, the formula for BMI is

'weight (lb) / [height (in)]^2 x 703'

and all the talk of "it's the cheapest and easiest way" ignores the fact that we could add other cheap measurements (like hip and shoulder circumference, or Age) or we could reexamine the formula without adding new variables to make it better.

You're too generous, that's over the 99th percentile. 95th is 6'2"- https://www.cdc.gov/growthcharts/data/set2/chart-07.pdf

It's fine if BMI breaks down at the 99.99th percentile, doctors can use their eyes.

If you are white use this formula to calculate body fat percentage with a standard error of the estimate (SEE) of 4.74%:

We studied a sample of 6,510 white subjects (2,154 men, 4,356 women), aged 18–80 years, including patients visiting our department. The study was performed to valuate the usefulness of a new equation: BF% = –44.988 + (0.503 x age) + (10.689 x sex) + (3.172 x BMI) – (0.026 x BMI^2) + (0.181 x BMI x sex) – (0.02 x BMI x age) – (0.005 x BMI^2 x sex) + (0.00021 x BMI^2 x age) where male = 0 and female = 1 for sex, and age in years, developed by multiple regression to predict BF%

This online calculator claims to use this algorithm:

https://www.omnicalculator.com/health/body-fat

Reference: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3263863/pdf/383...

Arnold Schwarzenegger hade an obese BMI in competition trim. Outliers does not invalidate a generic measure, they are outliers.

https://upload.wikimedia.org/wikipedia/commons/0/05/Arnold_S...

The argument of "BMI doesnt account for muscles/height" always sucks because of what you said, they're just outliers. Realistically nobody that is TRULY an outlier takes BMI into account in anyway.

Differences in body proportion, fat-free body density, and hydration may have a larger effect on the validity of body-composition devices in minority populations than previously assumed. Based on the review of literature, DXA is a valid method in a multi-ethnic sample, if individuals are Caucasian/White and African American/Black. However, there is insufficient evidence to recommend use in Hispanic/Latinx and Asian adults, Native American males, or African-American/Black females. ADP is valid for Hispanic and African-American/Black males when utilizing race-specific equations; however, results are inconclusive in other racial/ethnic groups and sexes. For BIA, body-composition estimates may be valid in a multi-ethnic sample, but the literature demonstrates disparate results between races/ethnicities. BIA may provide valid results in Hispanic and Native American populations, as well as Asian populations utilizing race-specific equations. However, BIA is still not recommended for African-American/Black individuals based on current data. The lack of validation using a multi-compartment model criterion limits the certainty of conclusions, particularly regarding the validity of ADP and BIA.

Glossary:

ADP: air displacement plethysmography

BIA: bioelectrical impedance devices / bioelectrical impedance analysis

Reference: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8528114/

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