Walk into a GPC, AAPF, or AWPC-affiliated meet and you’ll see “Best Lifter” decided by Glossbrenner, not Wilks. It’s a formula with a genuinely different origin story than the polynomial-based systems most lifters are used to.
Where Glossbrenner came from
Before Wilks existed, powerlifting used the Schwartz formula for men and the Malone formula for women — both built in the 1970s from limited competition data, before large-scale statistical regression was practical. When the APF needed an updated bodyweight coefficient system in 2004, statistician Herb Glossbrenner didn’t start from scratch — he averaged the Schwartz/Malone coefficient with the Wilks coefficient at each bodyweight, reasoning that Schwartz tended to favor lighter lifters while Wilks favored heavier ones, so an average of the two would land somewhere more balanced.
It’s a table, not an equation
This matters practically: unlike Wilks, DOTS, or IPF GL, Glossbrenner was never published as a clean polynomial or exponential formula. It exists as an official lookup table — coefficients published at 0.05kg bodyweight increments across the men’s (40–231kg) and women’s (40–169kg) ranges, with interpolation between rows for bodyweights that fall between listed values.
Why this makes it harder to implement correctly
A calculator claiming to compute “Glossbrenner” from a formula rather than the actual published table is, at best, approximating it. Because the table was built by averaging two independently-fitted curves, it doesn’t reduce to a clean equation the way Wilks does — the only way to get it exactly right is to use the real table values.
How our calculator handles this
Our Glossbrenner Calculator uses anchor points taken directly from the official APF/WPC published tables, with linear interpolation between them for bodyweights that fall in between — the same method the official documentation itself describes for values not explicitly listed.
Should you care which formula your federation uses?
Only if you’re chasing a Best Lifter award. For general “how strong am I relative to my bodyweight” purposes, Glossbrenner, Wilks, and DOTS all tell a broadly similar story at typical bodyweights — the meaningful differences show up mainly at the extremes and in exactly which number wins a trophy.