Calories and protein
Estimate your daily maintenance calories and protein for lifting. This calculator uses the same method as Your numbers in Strengthara.
Written by Strengthara (Zenta AB) · Updated
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Result
Enter your details and calculate. Your daily maintenance and protein estimate will appear here.
What is maintenance?
Maintenance calories, also called total daily energy expenditure (TDEE), are the energy you use in a day. Eating around that amount keeps your average weight broadly stable. It includes resting energy, digestion, daily movement and exercise.
Choose the closest activity level, then check the estimate against your weight trend over several weeks under similar weighing conditions. A single weigh-in can reflect water or food. If your average weight keeps changing, your real maintenance differs from the prediction. Recalculate when your weight or routine changes.
Choose your activity
Include work, walking and training across your whole week. The factor already includes exercise; do not add workout calories again.
| Activity level | Typical week | Factor |
|---|---|---|
| Sedentary | Mostly seated, little exercise. | 1.2 |
| Lightly active | Mostly seated, some walking and light exercise. | 1.375 |
| Moderately active | Regular exercise and movement through the day. | 1.55 |
| Active | A physically active day and frequent training. | 1.725 |
| Very active | Heavy physical work combined with demanding training. | 1.9 |
Protein for lifters
The research behind the app places protein for healthy adults who lift around 1.6–2.2 g per kg of body weight per day. Strengthara uses 1.8 g per kg of reference weight as one practical starting point. Training, sufficient energy and consistency matter too; the result is not a required supplement dose.
Reference weight is your body weight, capped at the weight that would give a BMI of 27 at your height. For example, at 180 cm that cap is 87.48 kg. This cap is a Strengthara design choice, not a finding from the protein studies or a recommended body weight. It may understate needs for a very muscular lifter.
These numbers are for maintenance. Protein needs during an energy deficit can be higher, especially for lean, trained lifters. This calculator does not prescribe a deficit, a surplus or a rate of weight change.
A worked example
A 30-year-old man at 180 cm and 80 kg has a resting estimate of 1,780 kcal. With moderate activity, 1,780 × 1.55 gives 2,759 kcal/day. Protein is 1.8 × 80 = 144 g/day. At the same height and 120 kg, maintenance becomes 3,379 kcal/day; protein uses the 87.48 kg reference cap and rounds to 157 g/day.
Who this is for
General information for healthy adults who strength train, not individual medical advice. Do not use these targets for children, pregnancy or breastfeeding. Ask your care team for individual guidance if you have kidney disease, a protein restriction, diabetes treated with glucose-lowering medication, an eating-disorder history or are receiving clinical obesity care.
Method
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We use Mifflin–St Jeor for resting energy (called BMR in the app), then multiply by the selected activity factor. The original study predicted resting expenditure in healthy adults aged 19–78; individual needs and people outside that range may differ.
Male equation: 10 × weight (kg) + 6.25 × height (cm) − 5 × age (years) + 5.
Female equation: 10 × weight (kg) + 6.25 × height (cm) − 5 × age (years) − 161.
Maintenance = unrounded resting estimate × activity factor. Sedentary 1.2; lightly active 1.375; moderately active 1.55; active 1.725; very active 1.9.
Protein (g/day) = 1.8 × the smaller of body weight (kg) and 27 × height (metres) × height (metres).
The activity factors and the BMI-27 cap are the app’s assumptions. The cited Mifflin paper supports the resting equation, not these activity factors. The protein research uses body weight; it does not validate our reference-weight cap.
Age and height are whole numbers; weight accepts one decimal in kilograms. Each final calorie and protein result rounds to a whole number, with halves rounded up. Maintenance uses the unrounded resting value, so it matches the app for the same inputs.
Sources
- A new predictive equation for resting energy expenditure in healthy individuals (1990)
Mifflin et al. · American Journal of Clinical NutritionAccessed
- Protein supplementation and resistance training: systematic review and meta-analysis (2018)
Morton et al. · British Journal of Sports MedicineAccessed
- Nutrition Recommendations for Bodybuilders in the Off-Season (2019)
Iraki et al. · SportsAccessed