Why powerlifting needs a bodyweight-adjusted score
A raw powerlifting total -- the sum of squat, bench press and deadlift -- is not a fair way to compare lifters who compete in different bodyweight classes. Bigger bodies can generally produce more absolute force than smaller ones, largely because a larger frame carries more muscle mass, so a heavier lifter's higher total does not by itself indicate greater relative strength or skill.
Bodyweight-adjusted formulas solve this by multiplying a lifter's total by a coefficient that depends on their bodyweight, producing a single comparable number regardless of weight class or sex. This is what allows a competition to award a single 'best lifter' prize across multiple bodyweight categories, rather than only ranking lifters within their own class.
How the polynomial scoring formulas work
Both Wilks and DOTS work the same basic way: a coefficient is calculated as 500 divided by a polynomial evaluated at the lifter's bodyweight, and the final score is the lifter's total multiplied by that coefficient. The Wilks formula uses a fifth-degree polynomial, with separate published constants for men and women; DOTS uses a fourth-degree polynomial, also with separate male and female constants.
Because heavier bodyweights are associated with higher totals but not in direct proportion, the polynomial produces a coefficient that shrinks as bodyweight increases -- a lighter lifter's total is multiplied by a larger number than an equally-totaling heavier lifter's, which is what allows the formula to reward strength relative to bodyweight rather than absolute size.
Both polynomials are only published as valid within a defined bodyweight range: roughly 40 to 201.9 kg for men and 40 to 154.53 kg for women under Wilks, and roughly 40 to 210 kg for men and 40 to 150 kg for women under DOTS. Bodyweights outside those ranges are calculated using the nearest valid endpoint, since the curves were not fitted to data beyond those limits.
- Wilks coefficient = 500 ÷ (a + b·x + c·x² + d·x³ + e·x⁴ + f·x⁵), where x = bodyweight (kg)
- DOTS coefficient = 500 ÷ (A + B·x + C·x² + D·x³ + E·x⁴), where x = bodyweight (kg)
- Score (either formula) = total lifted (kg) × coefficient
Worked comparison: the same total at different bodyweights
The table below applies both formulas to three male lifters who each total exactly 500 kg but compete at different bodyweights, using the published Wilks and DOTS coefficient constants. As bodyweight rises, the coefficient -- and therefore the score -- falls under both formulas, even though the total lifted is identical.
The two formulas produce close, but not identical, scores at every bodyweight in this example -- generally within a few points of each other -- because they were fitted to different datasets. This is a useful illustration of how similar results usually are between the two, and equally of why they are not exactly interchangeable.
| Bodyweight | Wilks coefficient | Wilks score | DOTS coefficient | DOTS score |
|---|---|---|---|---|
| 70 kg | 0.7494 | 374.7 | 0.7512 | 375.6 |
| 80 kg | 0.6827 | 341.3 | 0.6895 | 344.8 |
| 100 kg | 0.6086 | 304.3 | 0.6155 | 307.8 |
Which federations use which formula
USA Powerlifting (USAPL) adopted DOTS as its official bodyweight-adjusted scoring formula in 2020, replacing Wilks for meet best-lifter awards and rankings within that federation. Other federations continue to use the original Wilks formula, and the International Powerlifting Federation uses its own GL Points system for IPF-sanctioned competition.
Because each federation can choose its own bodyweight-adjustment formula, the same lifter's meet result can be reported with a different score depending on which federation, or which specific meet, they compete in -- it is worth checking which formula a given result uses before comparing it to another lifter's.
Why the scores aren't interchangeable
Wilks and DOTS scores for the same lifter are usually similar, as the worked example above shows, but they are not the same number and should not be treated as directly comparable. Each formula was fitted to its own dataset of competition results using its own polynomial degree and constants, so a DOTS score of, say, 400 does not mean the same thing as a Wilks score of 400.
The same caution applies to the IPF's GL Points system and any other bodyweight-adjustment formula: scores are only meaningful when compared against other scores computed with the same formula. Mixing formulas -- for example, ranking one lifter's Wilks score against another's DOTS score -- produces a comparison that looks valid but is not.
よくある質問
What is the difference between Wilks and DOTS?
Both are bodyweight-adjusted powerlifting scores that multiply a lifter's total by a coefficient derived from a polynomial fit to bodyweight. Wilks uses a fifth-degree polynomial from an earlier dataset; DOTS uses a fourth-degree polynomial fitted to more recent competition data and became USA Powerlifting's official formula in 2020. The two usually produce close, but not identical, scores for the same lifter.
Which federation uses which scoring formula?
USA Powerlifting (USAPL) has used DOTS as its official formula since 2020. The International Powerlifting Federation (IPF) uses its own GL Points system. Other federations may still use the original Wilks formula, so it is worth checking which formula a specific federation or meet applies before comparing results.
Can I compare my Wilks score to someone else's DOTS score?
No, not directly. Even though Wilks and DOTS scores are usually numerically close for the same lifter, they come from different polynomials fitted to different datasets. A valid comparison requires both scores to be calculated with the same formula.
Why did my score change even though my total stayed the same?
Because both Wilks and DOTS scores depend on bodyweight as well as total, a change in bodyweight alone -- without any change in your total -- shifts your coefficient and therefore your score. Losing bodyweight while maintaining the same total generally raises the score under both formulas, and gaining bodyweight at the same total generally lowers it.
Is a higher Wilks or DOTS score always better?
Within a single formula, a higher score indicates a greater total relative to bodyweight according to that formula's coefficient curve. Neither formula, however, has a fixed universal grading scale endorsed by a health authority; both are primarily relative-ranking tools used to compare lifters against each other in a competition or dataset, not against an absolute benchmark.
What bodyweight range are these formulas valid for?
The Wilks polynomial is published as valid for approximately 40-201.9 kg in men and 40-154.53 kg in women; the DOTS polynomial for approximately 40-210 kg in men and 40-150 kg in women. Bodyweights outside these ranges are calculated using the nearest valid endpoint, since neither curve was fitted to data beyond those limits.
参考文献
- Wikipedia contributors. Wilks coefficient. Wikipedia, the free encyclopedia — published male and female polynomial constants.
- Wikipedia contributors (German edition). DOTS-Relativwertung. Wikipedia, die freie Enzyklopädie — published DOTS coefficient constants.
- Vanderburgh PM, Batterham AM. Validation of the Wilks powerlifting formula. Medicine & Science in Sports & Exercise 1999; 31(12): 1869–1875.
- USA Powerlifting (USAPL). Official rules and scoring formula documentation.
- International Powerlifting Federation (IPF). Technical Rules — competition scoring formulas.