Casey Butt anthropometric model
Heuristic estimates of mass and girths from height, wrist, ankle and assumed body fat. The original girths describe male bodybuilders at about 8–10% fat. Berkhan: separate reference of height (cm) − 100 kg.
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Calculation
This calculation is for reference only and is not medical advice, a diagnosis or a prescription. If you have a medical condition, are pregnant, take medication or have any doubts, discuss the result with a physician or a qualified nutrition professional.
Result
- Estimated fat-free mass
- 80.8 kg
- Estimated weight at assumed body fat
- 89.8 kg
- Berkhan Contest Weight (shredded, ~5% body fat)
- 78.0 kg
- Estimated chest girth
- 119.4 cm
- Estimated upper arm girth
- 43.1 cm
- Estimated forearm girth
- 34.4 cm
- Estimated thigh girth
- 63.3 cm
- Estimated calf girth
- 42.5 cm
The male sample does not establish female norms. The model does not measure genetics, prove a muscular ceiling or predict time to achievement. Selected body fat is an assumption, not a recommended target.
The male sample does not establish female norms. The model does not measure genetics, prove a muscular ceiling or predict time to achievement. Selected body fat is an assumption, not a recommended target.
Martin Berkhan formula: Height (cm) − 100 at extreme contest conditioning
The male sample does not establish female norms. The model does not measure genetics, prove a muscular ceiling or predict time to achievement. Selected body fat is an assumption, not a recommended target.
How it is calculated
Heuristic estimates of mass and girths from height, wrist, ankle and assumed body fat. The original girths describe male bodybuilders at about 8–10% fat. Berkhan: separate reference of height (cm) − 100 kg.
Formula
Max LBM = Height^1.5 × [sqrt(Wrist)/22.6670 + sqrt(Ankle)/17.0104] × [(BodyFat%/224) + 1]; Berkhan Contest Weight (~5% BF) = Height (cm) − 100.
Limits of the method
The male sample does not establish female norms. The model does not measure genetics, prove a muscular ceiling or predict time to achievement. Selected body fat is an assumption, not a recommended target.
Sources of the method
How to use the calculation
Enter the starting values
Heuristic estimates of mass and girths from height, wrist, ankle and assumed body fat. The original girths describe male bodybuilders at about 8–10% fat. Berkhan: separate reference of height (cm) − 100 kg.
Adjust the parameters
Max LBM = Height^1.5 × [sqrt(Wrist)/22.6670 + sqrt(Ankle)/17.0104] × [(BodyFat%/224) + 1]; Berkhan Contest Weight (~5% BF) = Height (cm) − 100.
Read the result
The male sample does not establish female norms. The model does not measure genetics, prove a muscular ceiling or predict time to achievement. Selected body fat is an assumption, not a recommended target.
Frequently asked questions
What does the calculation show?
Heuristic estimates of mass and girths from height, wrist, ankle and assumed body fat. The original girths describe male bodybuilders at about 8–10% fat. Berkhan: separate reference of height (cm) − 100 kg.
What limitations apply?
The male sample does not establish female norms. The model does not measure genetics, prove a muscular ceiling or predict time to achievement. Selected body fat is an assumption, not a recommended target.
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