How Is Body Fat Calculated

US Navy Body Fat Formula:

For Men: 86.010 × log₁₀(abdomen - neck) - 70.041 × log₁₀(height) + 36.76

For Women: 163.205 × log₁₀(waist + hip - neck) - 97.684 × log₁₀(height) - 78.387

Gender:

Abdomen:

inches

Waist:

inches

Hip:

inches

Neck:

inches

Height:

inches

Body Fat Percentage:

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1. What is the US Navy Body Fat Formula?

The US Navy body fat formula is a method developed by the US Navy to estimate body fat percentage using body circumference measurements. It provides a practical and accessible way to assess body composition without specialized equipment.

2. How Does the Calculator Work?

The calculator uses the US Navy body fat formulas:

For Men: 86.010 × log₁₀(abdomen - neck) - 70.041 × log₁₀(height) + 36.76

For Women: 163.205 × log₁₀(waist + hip - neck) - 97.684 × log₁₀(height) - 78.387

Where all measurements are in inches:

Abdomen - Circumference at the navel level (men)
Waist - Circumference at the narrowest point (women)
Hip - Circumference at the widest point (women)
Neck - Circumference below the larynx
Height - Total height in inches

3. Importance of Body Fat Calculation

Details: Body fat percentage provides a more accurate assessment of health and fitness than body weight alone. It helps in monitoring fitness progress, assessing health risks, and setting appropriate fitness goals.

4. Using the Calculator

Tips: Select your gender first, then enter the required measurements in inches. For men: abdomen, neck, and height. For women: waist, hip, neck, and height. Ensure measurements are taken accurately for best results.

5. Frequently Asked Questions (FAQ)

Q1: How accurate is the US Navy body fat formula?
A: While not as precise as DEXA scans or hydrostatic weighing, it provides a reasonably accurate estimate (±3-4%) when measurements are taken correctly.

Q2: When should measurements be taken?
A: For consistency, take measurements in the morning before eating or drinking, and avoid measuring immediately after exercise.

Q3: What are healthy body fat percentages?
A: For men: 8-19% (athletic), 20-24% (acceptable), 25%+ (obese). For women: 21-33% (athletic), 34-39% (acceptable), 40%+ (obese).

Q4: Can this formula be used for all populations?
A: The formula was developed for military personnel and works best for adults aged 18-65. It may be less accurate for very athletic individuals, elderly, or those with unusual body proportions.

Q5: How often should I measure my body fat?
A: For tracking progress, measure every 4-8 weeks. Daily or weekly measurements may show fluctuations due to hydration and other factors.