Understanding the Harris-Benedict Equation
Before diving into memorization techniques, a quick review of the Harris-Benedict equations is necessary. The formulas estimate your Basal Metabolic Rate (BMR), which is the number of calories your body burns at rest to maintain basic functions. These calculations are foundational for creating diet and weight management plans. There are separate formulas for men and women due to physiological differences in body composition and metabolic rates.
The Revised Harris-Benedict Formulas (Metric System):
- Men: BMR = 88.362 + (13.397 × weight in kg) + (4.799 × height in cm) - (5.677 × age in years)
- Women: BMR = 447.593 + (9.247 × weight in kg) + (3.098 × height in cm) - (4.330 × age in years)
Mnemonics for Men's Equation
For the male formula, the constant numbers and their associated variables need to be memorized: 88.362, 13.397 (weight), 4.799 (height), and -5.677 (age).
The 'Hairy Bigfoot' Story
Using a memorable story is an excellent technique for remembering scientific formulas. Imagine a hairy, giant Bigfoot with specific characteristics and habits. This narrative links the numbers to the variables in a silly, vivid way:
- The Bigfoot's name is 88 (the constant, 88.362). He is an old man, and his age (5.677) makes him slow and lazy, so you must subtract it. This explains the negative age coefficient.
- His heavy, muscular weight requires a large number to multiply by: 13.397, which can be remembered as "13 BIG pounds, 97 of them." This reinforces the large weight coefficient.
- Despite his age, his height is impressive, so you add a significant number multiplied by it: 4.799. Think of it as "almost five" feet (or centimeters, to keep the metric theme) added on, giving him an imposing stature.
- The final male formula is
88 + (13 x weight) + (5 x height) - (6 x age). The simplified numbers (88, 13, 5, 6) are easier to remember, and you can fill in the precise decimals later once the core structure is locked in.
Mnemonics for Women's Equation
For the female formula, the constants are different but can be learned with a similar imaginative approach: 447.593, 9.247 (weight), 3.098 (height), and -4.330 (age).
The 'Glamorous Woman' Story
Create a contrasting story for the female equation to highlight the differences in the coefficients and constants:
- Start with the idea of a glamorous woman. Her constant is 447 (447.593). She's smaller and lighter than the Bigfoot, so her numbers are smaller.
- She focuses on her weight, but the multiplier is less than the man's: 9.247 (“just over 9”). This reflects the typically lower metabolic contribution of weight in women.
- She is proud of her height, but again, the multiplier is smaller: 3.098 (“about 3”). This contrasts with the larger multiplier for height in men.
- She wants to hide her age, so you must subtract a modest number multiplied by it: -4.330 (“four point three three”). This emphasizes the age factor as a smaller deduction compared to the male formula.
Practical Steps to Master the Formulas
Repeat and Visualize
- Flashcards: Use flashcards with the full formula on one side and a simplified mnemonic story on the other. This active recall method is highly effective.
- Write It Down: Practice writing the equations from memory repeatedly. Writing down information strengthens neural pathways associated with that memory.
- Recite Aloud: Speak the formulas and associated mnemonics aloud. Auditory repetition can help solidify the information in your long-term memory.
Compare and Contrast the Formulas
Creating a comparison table helps organize the information and highlights the differences, which is crucial for distinguishing between the male and female equations.
| Variable | Men's Equation (Metric) | Women's Equation (Metric) | Mnemonic Contrast |
|---|---|---|---|
| Base Constant | 88.362 | 447.593 | Large vs. Small: The male constant (88) is smaller than the female constant (447). |
| Weight (kg) | + (13.397 × W) | + (9.247 × W) | High vs. Low Multiplier: Man's weight is a more significant metabolic factor. |
| Height (cm) | + (4.799 × H) | + (3.098 × H) | Higher vs. Lower Growth Factor: The male height coefficient is larger. |
| Age (years) | - (5.677 × A) | - (4.330 × A) | Larger vs. Smaller Deduction: Age decreases BMR, but the effect is more pronounced in men. |
Conclusion: Making Complex Formulas Memorable
Mastering the Harris-Benedict equation is more than just raw memorization; it's about associating abstract numbers with concrete, memorable concepts. By using engaging and contrasting mnemonics like the 'Hairy Bigfoot' and 'Glamorous Woman' stories, students and professionals can imprint the formulas into their memory with greater ease. These techniques, combined with consistent practice and visualization, turn a potentially difficult task into a straightforward process, allowing you to confidently apply these foundational nutrition calculations in your practice. While more modern equations like the Mifflin-St Jeor formula are now widely used, understanding and remembering the classic Harris-Benedict is a valuable skill in the health and nutrition fields.
What are some great mnemonics for physics, chemistry and math? - Quora
While this article provides tailored mnemonics for the Harris-Benedict equation, those interested in broader memorization techniques for scientific formulas can find further inspiration in discussions like this Quora thread on great mnemonics for physics, chemistry, and math.
