Methods & References

Estimate resting metabolic rate from body mass, height, age and the equation sex constant.

male: 10·kg + 6.25·cm − 5·age + 5 | female: 10·kg + 6.25·cm − 5·age − 161

Inputs

Body mass (kg), height (cm), age (years), equation sex

Outputs & units

Resting metabolic rate (kcal/day)

Limitations

Predictive population equation; individual error can be substantial, particularly in high-lean-mass athletes.

• Primary studyMifflin MD, St Jeor ST, Hill LA, et al. A new predictive equation for resting energy expenditure in healthy individuals. Am J Clin Nutr. 1990.PMID 2305711Open source

Estimate resting metabolic rate from measured fat-free mass.

500 + 22 · FFM(kg)

Inputs

Fat-free mass (kg)

Outputs & units

Resting metabolic rate (kcal/day)

Limitations

Only as accurate as the fat-free mass measurement and its method; requires a documented body-composition assessment.

• Primary studyCunningham JJ. A reanalysis of the factors influencing basal metabolic rate in normal adults. Am J Clin Nutr. 1980.PMID 7435418Open source

Scale a selected resting metabolic rate by a professional-entered activity factor and an explicit planning adjustment.

RMR × activityFactor × (1 + adjustment%/100)

Inputs

Selected RMR, activity factor, adjustment percentage

Outputs & units

Baseline and adjusted kcal/day

Limitations

The activity factor is a professional judgement, not a measurement. Outputs are planning estimates and must be verified against intake and body-mass trend.

• Position standThomas DT, Erdman KA, Burke LM. Position of the Academy of Nutrition and Dietetics, Dietitians of Canada and ACSM: Nutrition and Athletic Performance. 2016.PMID 26891166Open source

Convert a day-demand carbohydrate range in g/kg/day into grams and kilocalories per day.

g/day = g/kg/day × body mass; kcal = g × 4

Inputs

Body mass, day demand band or custom range, selected point

Outputs & units

Minimum/maximum g/day, selected g/day and kcal/day

Limitations

Bands are planning ranges for populations of athletes, not individual prescriptions; adjust from observed training response.

• Position standThomas DT, Erdman KA, Burke LM. Position of the Academy of Nutrition and Dietetics, Dietitians of Canada and ACSM: Nutrition and Athletic Performance. 2016.PMID 26891166Open source
• Primary studyBurke LM, Hawley JA, Wong SHS, Jeukendrup AE. Carbohydrates for training and competition. J Sports Sci. 2011.PMID 21660838Open source
• Position standKerksick CM, et al. International Society of Sports Nutrition position stand: nutrient timing. JISSN. 2017.PMID 28919842Open source

Planning band of 1.4–2.0 g/kg body mass per day.

g/day = g/kg × body mass

Inputs

Body mass, selected g/kg

Outputs & units

g/day and kcal/day

Limitations

Distribution across the day and per-meal dose are separate considerations not modelled here.

• Position standJäger R, et al. International Society of Sports Nutrition position stand: protein and exercise. JISSN. 2017.PMID 28642676Open source

Planning band of 1.6–2.2 g/kg body mass per day.

g/day = g/kg × body mass

Inputs

Body mass, selected g/kg

Outputs & units

g/day and kcal/day

Limitations

Attributed to the uploaded sports-nutrition reference used for this independent build, not to a primary consensus statement.

• Uploaded referenceUploaded sports-nutrition reference text used for this independent build. Planning band only; not a primary consensus statement.
• Position standJäger R, et al. International Society of Sports Nutrition position stand: protein and exercise. JISSN. 2017.PMID 28642676Open source

Planning band of 2.3–3.1 g/kg fat-free mass per day in an energy-restricted resistance-trained context.

g/day = g/kg FFM × FFM

Inputs

Fat-free mass, selected g/kg FFM

Outputs & units

g/day and kcal/day

Limitations

Requires a measured fat-free mass; body mass is never substituted. Context-specific and not a default band.

• Primary studyHelms ER, Zinn C, Rowlands DS, Brown SR. A systematic review of dietary protein during caloric restriction in resistance-trained lean athletes. IJSNEM. 2014.PMID 24092765Open source

Convert a selected 20–35% of energy into grams of fat per day.

g/day = (kcal × pct/100) ÷ 9

Inputs

Energy target, selected percentage

Outputs & units

kcal/day and g/day

Limitations

Percentage-of-energy targets shift in absolute grams whenever the energy target changes.

• Position standThomas DT, Erdman KA, Burke LM. Position of the Academy of Nutrition and Dietetics, Dietitians of Canada and ACSM: Nutrition and Athletic Performance. 2016.PMID 26891166Open source

Sum selected carbohydrate, protein and fat energy and compare with the energy target.

total = 4·CHO + 4·PRO + 9·FAT; remaining = target − total

Inputs

Energy target and selected macronutrient grams

Outputs & units

Total, remaining/unallocated and percentage of target

Limitations

Uses standard Atwater factors and never adjusts a professional selection automatically.

• Position standThomas DT, Erdman KA, Burke LM. Position of the Academy of Nutrition and Dietetics, Dietitians of Canada and ACSM: Nutrition and Athletic Performance. 2016.PMID 26891166Open source

Derive sweat loss, sweat rate, raw mass change and net fluid balance from a measured session.

sweatL = (pre − post) + intakeL − urineL; rate = sweatL ÷ hours

Inputs

Pre/post mass, intake, urine, duration, chosen replacement fraction

Outputs & units

L, L/h, %, replacement range and mL per interval

Limitations

Mass change is a proxy only; respiratory water and substrate oxidation add error. Results are environment- and session-specific.

• Position standMcDermott BP, et al. National Athletic Trainers' Association position statement: fluid replacement for the physically active. 2017.PMC5634236Open source
• Uploaded referenceUploaded sports-nutrition reference text used for this independent build. Planning band only; not a primary consensus statement.

5–10 mL/kg body mass, 2–4 h before exercise.

minMl = 5 × kg; maxMl = 10 × kg

Inputs

Body mass

Outputs & units

mL range and timing window

Limitations

A starting range only; adjust from urine indices and individual tolerance.

• Position standMcDermott BP, et al. National Athletic Trainers' Association position statement: fluid replacement for the physically active. 2017.PMC5634236Open source

Convert selected pre, during and recovery bands into grams, per-feeding amounts and totals.

duringTotal = g/h × hours; perFeeding = duringTotal ÷ floor(minutes ÷ interval)

Inputs

Body mass, duration, context, selected g/kg and g/h, interval, recovery window

Outputs & units

Pre g and kcal, total and per-feeding g, recovery g

Limitations

Higher intakes require gut training and must be trialled in training. Tolerance is highly individual.

• Primary studyBurke LM, Hawley JA, Wong SHS, Jeukendrup AE. Carbohydrates for training and competition. J Sports Sci. 2011.PMID 21660838Open source
• Position standKerksick CM, et al. International Society of Sports Nutrition position stand: nutrient timing. JISSN. 2017.PMID 28919842Open source
• Primary studyBeelen M / Heaton LE et al. Selecting the optimal recovery nutrition strategy. Sports Med. 2015.PMID 26166054Open source

Total user-entered products against imported fueling and sweat requirements and expose any shortfall.

totals = Σ(perServing × servings); shortfall = target − total

Inputs

Requirement targets, event duration and interval, product servings

Outputs & units

Totals, per-interval amounts, shortfall or excess

Limitations

Only sums what the professional entered. It generates no caffeine or supplement dose and makes no product recommendation.

• Primary studyBurke LM, Hawley JA, Wong SHS, Jeukendrup AE. Carbohydrates for training and competition. J Sports Sci. 2011.PMID 21660838Open source
• Position standMcDermott BP, et al. National Athletic Trainers' Association position statement: fluid replacement for the physically active. 2017.PMC5634236Open source

Express net energy after exercise relative to fat-free mass as a context figure.

EA = (intake − EEE) ÷ FFM

Inputs

Energy intake, exercise energy expenditure, fat-free mass

Outputs & units

kcal/kg FFM/day with all intermediate values

Limitations

Both inputs carry large measurement error. This build applies no thresholds and makes no REDs determination; it is not a diagnostic tool.

• Consensus statementMountjoy M, et al. IOC consensus statement on Relative Energy Deficiency in Sport (REDs). Br J Sports Med. 2023;57:1073–1097.BJSM 57:1073–1097Open source

Derive BMI and, when a documented body-fat percentage exists, fat mass and fat-free mass.

BMI = kg ÷ m²; fatMass = kg × bf%/100; FFM = kg − fatMass

Inputs

Body mass, height, optional body-fat percentage with method and date

Outputs & units

BMI (kg/m²), fat mass (kg), fat-free mass (kg)

Limitations

No skinfold-to-percentage conversion is applied. Methods are not interchangeable, so cross-method comparisons are flagged rather than plotted together.

• Position standThomas DT, Erdman KA, Burke LM. Position of the Academy of Nutrition and Dietetics, Dietitians of Canada and ACSM: Nutrition and Athletic Performance. 2016.PMID 26891166Open source

Quantify internal session load in arbitrary units.

load = duration(min) × sRPE

Inputs

Session duration (min), session RPE (0–10)

Outputs & units

Load in arbitrary units, daily and weekly totals

Limitations

Arbitrary units are only comparable within one athlete. No acute:chronic ratio and no load prescription is produced.

• Primary studyFoster C, et al. A new approach to monitoring exercise training. J Strength Cond Res. 2001.PMID 11708692Open source

Structure a documented decision: purpose, food-first alternatives, rationale, batch testing and review date.

Inputs

Purpose, alternatives, evidence notes, certifier, lot, expiry, medications

Outputs & units

Decision status and review date

Limitations

This is a documentation record, not a dosing calculator. Third-party batch testing reduces but does not eliminate contamination risk.

• Consensus statementMaughan RJ, et al. IOC consensus statement: dietary supplements and the high-performance athlete. 2018.PMC5867441Open source
• GuidanceUSADA Supplement Connect — supplement risk guidance for athletes.Open source
• GuidanceInternational Testing Agency — athlete guidance on supplements and prohibited substances.Open source