The Bench Press Coefficient Calculator is a tool designed to normalize and compare bench press performances across individuals of different body weights. This is particularly important in competitive powerlifting, where the raw amount of weight lifted doesn’t always tell the whole story. The calculator uses specific formulas, such as the Schwartz and Wilks formulas, to calculate a coefficient that allows for fair comparisons by taking into account the lifter’s body weight.
This tool is essential for athletes, coaches, and fitness enthusiasts who want to evaluate strength performance on a level playing field, regardless of body weight. It also helps in setting goals, tracking progress, and ranking lifters in competitions where body weight is a significant factor.
Formula of Bench Press Coefficient Calculator
1. Schwartz Formula
The Schwartz Formula is used to calculate a coefficient that adjusts the weight lifted based on the lifter's body weight:
Schwartz Coefficient = (Lifted Weight) / (Body Weight ^ 0.67)
Where:
- Schwartz Coefficient is the normalized score for bench press strength.
- Lifted Weight is the amount of weight lifted during the bench press, measured in kilograms or pounds.
- Body Weight is the lifter’s body weight, measured in the same unit as the lifted weight.
This formula is straightforward and gives a coefficient that can be used to compare performances between lifters of different body weights.
2. Wilks Formula
The Wilks Formula is more complex and is widely used in powerlifting competitions to rank lifters across different weight classes:
Wilks Coefficient = Lifted Weight * Wilks Coefficient Factor
To calculate the Wilks Coefficient, the following steps are involved:
Wilks Coefficient Factor Calculation:
The Wilks Coefficient Factor is determined based on the lifter's body weight using the following formula, which differs for male and female lifters:
For Male Athletes:
Wilks Coefficient Factor = 500 / (a + b * Body Weight + c * Body Weight ^ 2 + d * Body Weight ^ 3 + e * Body Weight ^ 4 + f * Body Weight ^ 5)
For Female Athletes:
Wilks Coefficient Factor = 500 / (a + b * Body Weight + c * Body Weight ^ 2 + d * Body Weight ^ 3 + e * Body Weight ^ 4 + f * Body Weight ^ 5)
Coefficients for Male Athletes:
- a = -216.0475144
- b = 16.2606339
- c = -0.002388645
- d = -0.00113732
- e = 7.01863e-6
- f = -1.291e-8
Coefficients for Female Athletes:
- a = 594.31747775582
- b = -27.23842536447
- c = 0.82112226871
- d = -0.00930733913
- e = 4.731582e-5
- f = -9.054e-8
These formulas and coefficients ensure that the Wilks Coefficient accurately reflects the strength of lifters relative to their body weight, allowing for fair comparison across different weight classes.
Useful Conversion Table
To help users understand common terms and values used in the Bench Press Coefficient Calculator, the following table provides typical conversions and explanations:
| Term | Description | Common Values |
|---|---|---|
| Lifted Weight (kg) | The amount of weight lifted, measured in kilograms. | 100kg, 120kg, 150kg |
| Lifted Weight (lbs) | The amount of weight lifted, measured in pounds. | 220lbs, 265lbs, 330lbs |
| Body Weight (kg) | The lifter’s body weight, measured in kilograms. | 70kg, 80kg, 90kg |
| Body Weight (lbs) | The lifter’s body weight, measured in pounds. | 154lbs, 176lbs, 198lbs |
| Schwartz Coefficient | The normalized bench press score using the Schwartz Formula. | Varies based on inputs |
| Wilks Coefficient | The normalized bench press score using the Wilks Formula. | Varies based on inputs |
This table provides a quick reference for users to input data and understand the results generated by the Bench Press Coefficient Calculator.
Example of Bench Press Coefficient Calculator
Let's calculate the Schwartz and Wilks coefficients for a male lifter with the following parameters:
- Lifted Weight: 120kg
- Body Weight: 80kg
Schwartz Coefficient Calculation
Using the Schwartz Formula:
Schwartz Coefficient = 120kg / (80kg ^ 0.67) = 120kg / 32.26 = 3.72
Wilks Coefficient Calculation
First, calculate the Wilks Coefficient Factor using the provided coefficients for male athletes:
Wilks Coefficient Factor = 500 / (-216.0475144 + 16.2606339 * 80 + (-0.002388645) * 80^2 + (-0.00113732) * 80^3 + 7.01863e-6 * 80^4 + (-1.291e-8) * 80^5) = 500 / (634.21) = 0.788
Then, calculate the Wilks Coefficient:
Wilks Coefficient = 120kg * 0.788 = 94.56
Most Common FAQs
Calculating bench press coefficients like the Schwartz and Wilks coefficients allows for fair comparison of strength across different body weights. This is essential in powerlifting and strength competitions to ensure that lifters of all sizes are evaluate on a level playing field.
The choice between the Schwartz and Wilks coefficients depends on the specific competition or context. The Wilks formula is more commonly use in powerlifting competitions, while the Schwartz formula may be use in more general fitness settings. Both provide valuable insights, but the Wilks formula is consider more comprehensive.
Yes, the Bench Press Coefficient Calculator can be adapt for other lifts such as squats and deadlifts. The formulas are generally applicable to any strength lift where body weight normalization is need to compare performances fairly.