Carb cycling

Carb cycling means varying carbohydrate intake across the week rather than eating the same amount every day: typically higher on hard training days and lower on rest or easy days, with protein held steady and fat moving inversely.

The logic is intuitive and reasonable. Carbohydrate is the fuel that hard training depends on, so putting more of it where the demand is and less where it is not matches supply to need without changing the weekly total.

The evidence for it as a fat loss method is much thinner than the logic suggests. Studies comparing varied and steady intakes at matched weekly calories and protein generally find similar outcomes, which is what you would expect if energy balance is doing the work.

Where it plausibly helps is training quality and adherence. Fuelling the sessions that need fuelling can make them better, and some people find that having genuinely higher days makes a long diet easier to tolerate than a uniformly restricted one.

The costs are complexity and error. It requires more planning, more tracking and more opportunities to miscount, and for someone who is not already reliably hitting their weekly numbers it adds precision where none is needed.

The scale will also move more, since glycogen and its associated water rise and fall with intake, which makes progress harder to read day to day and easier to misinterpret.

In practice, get the weekly total and protein right first. If you then want to redistribute carbohydrate towards your hard sessions, that is a sensible refinement rather than a mechanism, and our macro calculator will handle the arithmetic.