Methodology & Sources

Energy & macros

• BMR / TDEE — Mifflin–St Jeor (1990), the most accurate general resting-energy prediction equation in peer-reviewed reviews; TDEE applies standard activity multipliers (1.2–1.9).
• Macros — protein at 2 g/kg bodyweight, fat at 25% of calories, carbohydrate as the remainder; goal calories adjust TDEE by −20% (fat loss) or +10% (lean gain).
• Calorie deficit — ~7,700 kcal ≈ 1 kg of body fat; weekly loss projected from the daily deficit.

Body composition

• BMI — weight ÷ height². A population screen, not an individual body-composition measure.
• Body fat % — U.S. Navy circumference method (sex-specific, log-based).
• Lean body mass — Boer formula.
• Ideal weight — Robinson, Miller, Devine, Hamwi, plus a healthy BMI band; shown as a range because the formulas disagree by design.
• Body surface area — Du Bois and Mosteller.

Training

• One-rep max — Epley and Brzycki, averaged; most accurate at 1–10 reps.
• Wilks — original 1996 Wilks coefficient for cross-bodyweight comparison.
• Heart-rate zones — Tanaka max HR (208 − 0.7 × age), more accurate than 220 − age.
• Running pace — distance/time, even-pace model.

Other

• Protein — goal-based g/kg ranges from sports-nutrition guidelines.
• Water intake — ~30–35 ml/kg baseline plus an activity adjustment.
• Pregnancy weight gain — Institute of Medicine (IOM, 2009) ranges by pre-pregnancy BMI, singleton pregnancy.

Key references

• Mifflin MD, St Jeor ST, et al. Am J Clin Nutr. 1990;51(2):241–247.
• Frankenfield D, Roth-Yousey L, Compher C. J Am Diet Assoc. 2005;105(5):775–789.
• Hodgdon JA, Beckett MB. U.S. Navy body-fat circumference method (1984).
• Boer P. Am J Physiol. 1984;247(4):F632–636.
• Tanaka H, Monahan KD, Seals DR. J Am Coll Cardiol. 2001;37(1):153–156.
• Institute of Medicine. Weight Gain During Pregnancy. 2009.

Estimates for general educational use only — not medical advice. See our editorial policy on the About page.