Macronutrients: protein, carbohydrates, and fat. The three calorie sources. Protein/carbs = 4 kcal/g; fat = 9 kcal/g.
Macros (macronutrients) are the three energy-providing nutrients in food: protein, carbohydrates, and fat. Alcohol is technically a fourth (7 kcal/g) but not one of the three meal-planning macros.
Atwater factors (energy per gram): protein 4 kcal, carbs 4 kcal, fat 9 kcal. A "40/30/30" macro split means 40% of calories from protein, 30% from carbs, 30% from fat — common for cutting (fat loss) phases.
2500 kcal at 30/40/30
188g protein (750 kcal), 250g carbs (1000), 83g fat (750)
2500 kcal at 40/30/30 (cut)
250g protein, 188g carbs, 83g fat
Macros Split
Split daily calories into protein, carbs, and fat grams for cutting, maintaining, or bulking.
BMR & TDEE
Basal metabolic rate and total daily energy expenditure using the Mifflin-St Jeor equation + activity multiplier.
Protein Needs
Daily protein target by bodyweight, activity, and goal — with breakpoints from sedentary to athletic.