Clinical guides

Evidence, explained — then calculated.

Concise, citable explainers reviewed by our medical board. Each guide links straight to the calculators that put it to work.

Fuel & Fasting6 MIN READ

How many calories should I eat per day?

A clinical walkthrough of energy balance, TDEE, and how to set a calorie target you can actually hold.

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Gym & Strength5 MIN READ

How much protein do you actually need?

Evidence-based protein targets for fat loss, muscle gain and healthy ageing — in grams, not guesswork.

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Cardio & Burn7 MIN READ

Heart-rate training zones, explained

What Z1–Z5 actually mean, how to find your max heart rate, and how to train each zone.

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Sleep & Circadian5 MIN READ

How to calculate and clear sleep debt

Sleep debt accumulates faster than you can repay it. Here is the clinical way to measure and recover.

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