Estimated Basal Metabolic Rate for a 9½-Year-Old Active Girl
For this 9½-year-old girl weighing 24.9 kg (55 lbs), the basal metabolic rate (BMR) is approximately 991 kcal/day using the Schofield equation, and her total daily energy expenditure is approximately 1,684-1,982 kcal/day accounting for her very active lifestyle.
BMR Calculation Using Schofield Equation
The ESPGHAN/ESPEN guidelines recommend using the Schofield equation for calculating resting energy expenditure (REE) in children 1. For girls aged 3-10 years, the equation is:
REE (kcal/day) = 20.3 × weight (kg) + 486
For this patient:
- Weight: 24.9 kg
- REE = (20.3 × 24.9) + 486 = 991 kcal/day
This represents her basal metabolic rate—the energy needed for vital body processes at rest 1.
Total Energy Needs for a Very Active Child
BMR alone does not account for physical activity or growth. The guidelines specify that total energy expenditure must include 1:
- Basal metabolic rate (BMR): 991 kcal/day (calculated above)
- Diet-induced thermogenesis (DIT): ~10% of daily needs
- Physical activity (PA): Varies by activity level
- Growth: ~20 kcal/day for healthy children this age
Physical Activity Level (PAL) Multipliers
The guidelines provide specific PAL multipliers to apply to BMR 1:
- PAL 1.5 = light activity
- PAL 1.7 = moderate activity (typical healthy children)
- PAL 2.0 = vigorous/very active
Since this child is described as "very active," a PAL of 1.7-2.0 is appropriate.
Total Daily Energy Calculation
For moderate-to-vigorous activity:
- Lower estimate: 991 × 1.7 = 1,685 kcal/day
- Upper estimate: 991 × 2.0 = 1,982 kcal/day
Adding growth needs (+20 kcal/day) is already incorporated in these PAL multipliers for practical purposes 1.
Important Clinical Considerations
The Schofield equation is the preferred method because it was least likely to underestimate REE compared to measured values and is specifically recommended by ESPGHAN/ESPEN guidelines with strong consensus 1. Research confirms these equations provide reliable estimates in healthy children aged 5-16 years 2.
Key Caveats
- BMR vs. REE distinction: In practice, REE (resting energy expenditure) and BMR differ by less than 10%, so these terms are often used interchangeably 1
- Individual variation: Predictive equations account for approximately 70% of metabolic variability; actual needs may vary by 10-20% 1, 3
- Body composition matters: Fat-free mass is the strongest predictor of metabolic rate, but weight-based equations like Schofield remain most practical 4, 3
- Enteral vs. parenteral: These calculations assume normal oral/enteral feeding; parenteral nutrition requirements would be 10-20% lower 1
When to Measure Rather Than Calculate
Indirect calorimetry should be considered if this child had 1:
- Suspected metabolic alterations
- Severe malnutrition or failure to thrive
- Chronic disease states affecting metabolism
For a healthy, very active 9½-year-old girl, the calculated estimate of 1,685-1,982 kcal/day total energy expenditure is clinically appropriate for nutritional planning and assessment.