Our Methodology

01 Why we document this

02 Tool formulas

The eight formulas and rule sets below power all current NoGymLab calculators. Each entry shows the equation, which tools use it, and the publication it was validated in.

• Mifflin-St Jeor Calorie Deficit · TDEE · IF

  Men:   RMR = (10 × weight_kg) + (6.25 × height_cm) − (5 × age) + 5
  Women: RMR = (10 × weight_kg) + (6.25 × height_cm) − (5 × age) − 161

  Most accurate resting metabolic rate estimate for non-athletes.

  Frankenfield D. et al., J Am Diet Assoc, 2005 · PMID 15883556

• Cunningham TDEE (LBM variant) · Recomp

  RMR = 500 + (22 × lean_body_mass_kg)

  Preferred for athletes where lean mass is known.

  Cunningham JJ., Am J Clin Nutr, 1980 · PMID 7369169

• TDEE Activity Multipliers All TDEE tools

  Sedentary          ×1.200
  Lightly active     ×1.375
  Moderately active  ×1.550
  Very active        ×1.725
  Extremely active   ×1.900

  Applied to RMR to estimate total daily energy expenditure.

  Harris-Benedict 1919 / Roza-Shizgal revision 1984

• Protein Intake Targets Macro Calculator · Cutting Protocol

  Fat loss:           1.6–2.4 g/kg body weight
  Muscle gain:        1.6–2.2 g/kg body weight
  Maintenance:        1.2–1.6 g/kg body weight
  Aggressive deficit: up to 3.1 g/kg LBM

  Ranges account for training age, body composition, and goal.

  Stokes T. et al., Nutrients, 2018 · Morton RW et al., BJSM, 2018 · Helms ER et al., JISSN, 2014

• BMI (WHO Classification) BMI Calculator

  BMI = weight_kg ÷ (height_m)²

  WHO cut-points used. BMI does not account for body composition.

  WHO Expert Consultation, Lancet, 2004 · Romero-Corral A. et al., Int J Obes, 2008

• Lean Body Mass — Boer LBM Calculator · TDEE

  Men:   LBM = (0.407 × weight_kg) + (0.267 × height_cm) − 19.2
  Women: LBM = (0.252 × weight_kg) + (0.473 × height_cm) − 48.3

  Population-validated LBM estimate from anthropometric inputs only.

  Boer P., J Appl Physiol, 1984 · PMID 6737172

• Epley equation — estimated one rep max 1RM + Double-Progression Estimator

  Epley:    1RM = w × (1 + r ÷ 30)     r = reps + RIR
            r = 1  →  1RM = w
  Brzycki:  1RM = w × 36 ÷ (37 − r)   cross-check
  Load at n reps = 1RM ÷ (1 + n ÷ 30)
  Cap: r ≤ 10, no estimate above

  Epley is the headline value; Brzycki is shown beside it, and the gap between them is formula spread, not an error margin. Capped at 10 reps because rep-based prediction is supported up to 10, and reps in reserve count toward the cap. Accuracy varies by person and exercise. Dumbbell values are per hand. There is no resistance-band mode: band tension changes with stretch, so one load and rep count cannot describe the effort. Last reviewed: October 2026.

  Epley B., 1985 · Brzycki M., JOPERD, 1993 · Grgic J. et al., Sports Med Open, 2020 · PMID 32681399 · Reynolds JM. et al., J Strength Cond Res, 2006 · PMID 16937972 · Nuzzo JL. et al., Sports Med, 2024 · PMID 37792272

• Double progression rules 1RM + Double-Progression Estimator

  Every set ≥ top of range → next weight step,
                             targets reset to bottom
  Otherwise → same weight, +1 rep per set (max = top)
  Jump check, avg ≤ 10 reps:
    E = w × (1 + avg ÷ 30); predicted = 30 × (E ÷ next − 1)
  Jump check, avg > 10 reps (approximate):
    predicted ≈ avg − 40 × jump%
  No heavier weight → ladder

  Verdict: predicted reps at or above the bottom of the range = good jump; up to 2 below = big jump; more than 2 below = too big, bridge first. The rule of thumb of about 2 fewer reps per 5% more load (5–10 reps) is derived from the Epley equation, not from a study. A set below the range is flagged but the weight is never lowered automatically. The ladder (extend the rep ceiling, slower lowering, pause, extra set, harder variation, re-estimate) is practical coaching guidance. Last reviewed: October 2026.

  Plotkin D. et al., PeerJ, 2022 · PMID 36199287 · Zourdos MC. et al., J Strength Cond Res, 2016 · PMID 26049792

03 Research sources

Primary citations are drawn from PubMed-indexed journals. We do not cite secondary summaries or general-interest health websites in place of original studies.

04 Visual execution standards

Exercise illustrations and diagrams follow four production rules to ensure accuracy and reproducibility.

1. 01

   Exercise demonstrations use neutral anatomical positions that are reproducible without equipment or a trainer present.

2. 02

   Diagrams prioritise functional clarity over aesthetic complexity — every element serves the instruction.

3. 03

   All visual assets are original or properly licensed; no stock exercise photos are used without verifying the depicted form.

4. 04

   Illustrations are reviewed by the domain author before publication and updated when technique guidance evolves.

05 Review process

Every article and tool follows a five-stage process from research to publication.

1. 01 Research

   The responsible author identifies primary sources and selects formulas or protocols with the strongest evidence base for the intended audience.

2. 02 Draft

   Content is drafted with inline citations. Every formula, figure, and claim is linked to its source before internal review begins.

3. 03 Cross-review

   The other author independently tests all calculations, checks that citations support the claims, and flags any scope limitations not already stated.

4. 04 Quality check

   Content is checked for readability, accurate language, and consistent use of units and notation before the final publication pass.

5. 05 Publish & schedule

   Published pages carry a "Last reviewed" date and are placed in the annual review queue. Time-sensitive changes are handled as corrections.

06 Our commitments

• 📄

  Source transparency

  Every formula and figure links to its published origin. Readers can follow every citation directly to the source.

• 📅

  Version dating

  Every page and tool carries a "Last reviewed" date. When a formula is updated, the previous version and its deprecation date are logged here.

• ✔

  Correction priority

  Confirmed errors are corrected before new content is published. We acknowledge reports within 5 working days.

• 🚫

  No affiliate influence

  Formula choices are never modified for commercial or sponsorship reasons. No undisclosed paid content appears on NoGymLab.