Science-based
fitness calculators.

What is TDEE?

TDEE (Total Daily Energy Expenditure) is the total calories your body burns in 24h — including basal metabolism, activity and digestion.

The calculation is based on the Mifflin-St Jeor formula:

• Maintenance — eat exactly your TDEE
• Cut — 300–500 calories less
• Bulk — 200–400 calories more

Why is protein critical?

Protein is the building block of muscle tissue. Recent research establishes:

• 1.6–2.2 g/kg — optimal for hypertrophy
• 4–5 meals of 0.4 g/kg
• 2.0–2.4 g/kg in a deficit — muscle protection

What is 1RM?

The maximum weight you can lift for a single repetition. Brzycki and Epley formulas:

• 85–100% — strength, 1-5 reps
• 65–85% — muscle, 6-12 reps
• 50–65% — endurance, 12-20

Natural potential?

The Martin Berkhan model is based on thousands of drug-free athletes:

Important: this is the ceiling after 5–10 years of precise training. Even 70–80% of this number is an impressive achievement.

Where do you stand?

The standards are based on databases of thousands of lifters:

• Beginner — 3–6 months of training
• Intermediate — 1–2 years
• Advanced — 3–5 years, ~15% of lifters
• Elite — few, competitive level

Creatine monohydrate

Over 1,000 studies confirm efficacy, safety and significant supplemental value. Two methods:

How long will it take?

The pace depends on your starting body fat %:

Beyond 16 weeks requires diet breaks of 1–2 weeks every 8–12 weeks.