06/12/2026
Body fat is not a binary positive or negative. A certain amount is necessary for preserving athlete health - and therefore training consistency and performance.
The optimal body composition is a range that allows for genetic variability - rather than a specific number that all athletes must aim for.
The optimal range for body composition is sport-specific. The demands of each sport select for certain body compositions.
For example, swimmers benefit from more body fat than runners. Lifters benefit from more body fat than sprinters.
Most sports include outlier athletes on either side of the optimal range.
For hybrid sport, the optimal range is likely still being discovered. These sports are young relative to others, and it takes decades to refine best practices. We still see plenty of variability at the start line.
We’re also limited by small sample sizes, which is common when profiling elite athletes. There just aren’t very many of them.
Here are some reasons why I think CrossFit is selecting for these ranges (continued in comments).