Cutting vs bulking: setting calories for each

Cutting and bulking sound like opposites, and in one sense they are — one strips fat, the other builds muscle. But they are really the same dial turned in different directions, and both are set from the same starting point: the number of calories that holds your weight steady.

Start from maintenance

Your maintenance calories are the amount that keeps your weight level. Everything else is a step away from it, because weight change follows the running balance between the energy you take in and the energy you burn. Find that number first; the cut or bulk is just a deliberate offset from it.

Setting a cut

For a cut, drop below maintenance by a modest amount — about 300 to 500 calories for most people, which works out near 0.5 to 1% of body weight lost per week. That pace is brisk enough to see progress and gentle enough to protect muscle and sanity; public-health guidance likewise favours a gradual rate you can actually sustain. Bigger deficits rarely pay off: they cost muscle, energy, and adherence.

Setting a bulk

For a bulk, sit above maintenance — but only a little. A surplus of roughly 200 to 400 calories a day is plenty to build muscle for most people, adding perhaps 0.25 to 0.5% of body weight per week. The temptation to "eat big" backfires: past a modest surplus, the extra calories mostly land as fat, not muscle, because there is a ceiling on how fast you can build. Lean and patient beats fast and fatty.

Protein does not change

Whichever direction you are going, keep protein high. Pooled training research points to around 1.6 grams per kilogram of body weight as the point where muscle gains are largely maxed out, with a nudge higher useful during a cut. In a bulk it builds new muscle; in a cut it defends the muscle you have. It is the one macro that stays put while the calories move.

How long to run each

Phases work best in blocks rather than open-endedly. A cut is usually run until you reach your target leanness or your energy and adherence start to fray — often 8 to 16 weeks — with a diet break at maintenance if it drags on. A bulk can run longer, several months, because building muscle is inherently slow and there is no benefit to rushing it. Many people cycle the two: build for a while, cut to reveal it, then build again. The exact numbers matter less than the principle — commit to a phase long enough to see a result, but not so long that it stops being sustainable.

A third option: staying put

Not everyone needs to cut or bulk. If you are reasonably happy with your body fat, eating around maintenance while training hard and hitting protein lets you slowly recompose — losing a little fat and gaining a little muscle over time. It is the least dramatic path and the easiest to live on indefinitely, which for many people makes it the most sensible default between more deliberate cutting and bulking phases.

The mistakes that waste a phase

• The "dirty bulk." Eating everything in sight adds far more fat than muscle and leaves a longer cut to undo it. Keep the surplus modest.
• The crash cut. Too steep a deficit costs muscle and strength — exactly what a lifter is trying to keep. Aim for the 300-to-500 range.
• Head-spinning switches. Flipping between cut and bulk every couple of weeks gives neither time to work. Pick a direction and give it a real run.
• Dropping protein in a bulk. Extra calories are not a licence to let protein slide; it is what turns the surplus into muscle rather than fat.

How Eat'n'Fit helps

Eat'n'Fit works out your maintenance number, so setting a cut or a bulk is just choosing an offset — and it tracks your protein alongside calories so it stays on target through either phase. Watch your weight trend to confirm the pace is what you intended, and adjust the offset if the trend is moving faster or slower than you planned.