1. What is the Womersley Formula?

Definition: The Durnin-Womersley formula estimates body fat percentage using skinfold measurements at four sites.

Purpose: It provides a practical method for assessing body composition without expensive equipment.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( a \) and \( b \) — Gender and age-specific constants
• \( \Sigma(\text{Skinfolds}) \) — Sum of four skinfold measurements (mm)

Explanation: The formula uses logarithmic transformation of skinfold measurements to estimate body density, which is then converted to body fat percentage.

3. Importance of Body Fat Measurement

Details: Body fat percentage is a key health indicator, helping assess fitness levels, nutritional status, and disease risk.

4. Using the Calculator

Steps:

1. Select your gender
2. Enter your age
3. Input four skinfold measurements (triceps, biceps, subscapular, suprailiac)
4. Click "Calculate"

Note: Skinfold measurements should be taken by a trained professional for accuracy.

5. Frequently Asked Questions (FAQ)

Q1: What are the standard measurement sites?
A: Triceps, biceps, subscapular, and suprailiac skinfolds are used in the 4-site Durnin-Womersley method.

Q2: How accurate is this method?
A: With proper technique, it's about ±3-5% of more advanced methods like DXA scanning.

Q3: Why does age matter in the calculation?
A: Body composition changes with age, so different constants are used for different age groups.

Q4: Can I use this for athletes?
A: Yes, but some sport-specific equations might be more appropriate for certain athletes.

Q5: What's a healthy body fat percentage?
A: For men: 8-19% (athletes) to 21-25% (acceptable); For women: 21-28% (athletes) to 31-36% (acceptable).