How our numbers are worked out.

Below is exactly how each calculator and recommendation in the Master Your Foundations app is worked out, with the published methods and guidelines behind each one so you can check the evidence yourself.

Important: not medical advice

This app provides general health and wellbeing education and estimates, not medical advice, diagnosis, or treatment, and it is not a substitute for care from a qualified professional. Nathan May and Mens Health Collective are not your physician. Every figure here is a general estimate, not a personalised prescription. Always consult your doctor or a registered health professional before changing your diet, exercise, supplement, or recovery routine, especially if you are pregnant, have a medical condition, or take medication.

Nutrition calculators

How the calorie, protein, hydration, and electrolyte figures are produced.

Daily calorie estimate

Method: resting metabolic rate from the Mifflin-St Jeor equation (10 x weight kg + 6.25 x height cm minus 5 x age, plus 5 for men or minus 161 for women), multiplied by an activity factor (1.2 sedentary to 1.9 very active) and a goal factor (0.80 fat loss, 1.0 maintain, 1.10 muscle gain).

Mifflin MD, St Jeor ST, et al. A new predictive equation for resting energy expenditure in healthy individuals. American Journal of Clinical Nutrition (1990). · View on PubMed

Activity multipliers (1.2 to 1.9)

Method: resting metabolic rate multiplied by a standard activity factor (1.2 sedentary up to 1.9 very active), following the convention used with the Harris-Benedict and Mifflin-St Jeor equations. The broader principle of scaling resting energy by a physical activity level is set out by the FAO/WHO/UNU consultation.

FAO/WHO/UNU. Human Energy Requirements: Report of a Joint Expert Consultation (2004). · Read the report

Protein target (1.6 to 2.2 g per kg of bodyweight)

Method: bodyweight multiplied by a value in the 1.6 to 2.2 g/kg range used for active adults building or maintaining muscle.

Iraki J, Fitschen P, Espinar S, Helms E. Nutrition Recommendations for Bodybuilders in the Off-Season: A Narrative Review. Sports (2019). · Read the review | Jäger R, et al. ISSN Position Stand: Protein and Exercise. JISSN (2017). · PubMed

Daily water target (about 33 ml per kg, plus sweat losses)

Method: a baseline of roughly 33 ml of fluid per kg of bodyweight, plus an estimated allowance for fluid lost through sweat during activity. The 33 ml/kg baseline is a practical rule of thumb that lands close to the total daily water intakes set by EFSA (about 2.0 L for women and 2.5 L for men). Shown on the page as "kg x 0.033 + sweat".

EFSA Panel on Dietetic Products, Nutrition and Allergies. Scientific Opinion on Dietary Reference Values for water (2010). · Read the opinion | Sawka MN, et al. ACSM Position Stand: Exercise and Fluid Replacement. MSSE (2007). · PubMed

Electrolyte guidance

Method: general sodium, potassium, and magnesium guidance calibrated to the published per-serve content of common electrolyte products; intended as a starting point, not a clinical dose.

Sawka MN, et al. ACSM Position Stand: Exercise and Fluid Replacement. Medicine & Science in Sports & Exercise (2007). · View on PubMed

Whole-food, fibre-forward eating patterns

U.S. Departments of Agriculture and Health & Human Services. Dietary Guidelines for Americans, 2020-2025. · DietaryGuidelines.gov

Training

The basis for the workout structure and volume guidance.

Weekly training volume drives muscle growth

Schoenfeld BJ, Ogborn D, Krieger JW. Dose-response relationship between weekly resistance training volume and increases in muscle mass. Journal of Sports Sciences (2017). · View on PubMed

Progressive overload and rep / RPE programming

American College of Sports Medicine. Position Stand: Progression Models in Resistance Training for Healthy Adults. MSSE (2009). · View on PubMed

Recommended activity and muscle-strengthening for adults

World Health Organization. WHO Guidelines on Physical Activity and Sedentary Behaviour (2020). · Read the guidelines

Recovery

The basis for the breathwork, sleep, and soft-tissue guidance.

Brief structured breathing (including the physiological sigh) can improve mood and lower arousal

Balban MY, et al. Brief structured respiration practices enhance mood and reduce physiological arousal. Cell Reports Medicine (2023). · View on PubMed

Slow, paced breathing shifts the nervous system toward calm

Russo MA, Santarelli DM, O'Rourke D. The physiological effects of slow breathing in the healthy human. Breathe (2017). · Read the article

Recommended sleep duration for adults

Watson NF, et al. Recommended Amount of Sleep for a Healthy Adult: joint consensus of the American Academy of Sleep Medicine and Sleep Research Society. Sleep (2015). · View on PubMed

Foam rolling for recovery and range of motion

Wiewelhove T, et al. A meta-analysis of the effects of foam rolling on performance and recovery. Frontiers in Physiology (2019). · Read the meta-analysis