How many calories to eat to cut or bulk

Step 1: your resting burn

The Mifflin-St Jeor equation is the most reliable of the common formulas. In a review that compared them, it came within 10% of measured resting burn for more people than any other.

• Men: 10 × weight (kg) + 6.25 × height (cm) − 5 × age + 5
• Women: 10 × weight (kg) + 6.25 × height (cm) − 5 × age − 161

For a man who's 27, 180 cm and 82 kg: 820 + 1,125 − 135 + 5 = 1,815 kcal a day at rest.

Step 2: add your activity

Multiply by how active you are. The Macromaxxing app starts at 1.2 and adds 0.075 for each training day, plus 0.15 if your job keeps you on your feet. Four training days and a desk job: 1,815 × 1.5 = about 2,725 kcal. That's roughly what you burn.

Step 3: cut or bulk

Cutting: eat about 400 kcal under what you burn. Aim to lose 0.5 to 1% of your bodyweight a week. In one study of trained athletes, the slower group (about 0.7% a week) gained lean mass while the faster group (about 1.4% a week) didn't.

Lean bulking: eat about 200 to 300 kcal over. Aim to gain 0.25 to 0.5% of your bodyweight a week; faster mostly adds fat.

Step 4: adjust

Any formula is a starting point. Weigh yourself a few times a week, compare weekly averages, and move your calories by 100 to 200 if you're not moving at the rate you want.

Skip the math with the calorie and protein calculator, then let the app plan meals that land on your number.