Protein is the most important macronutrient for anyone training. Getting your daily target right is what preserves muscle in a diet and builds it in a surplus.
Why bodyweight, not calories?
Protein needs track lean tissue, which scales with bodyweight — so grams-per-kilogram is the most reliable way to set a target, independent of how many total calories you eat.
Distribution matters
Muscle-protein synthesis responds to each protein feeding. Hitting roughly 0.4 g/kg per meal, 3–5 times a day, produces a better anabolic response than skewing all your protein into one meal.
Frequently asked questions
For general health, 0.8–1.2 g per kg of bodyweight. To build or retain muscle while training, 1.6–2.2 g/kg is well supported by research, with dieters benefiting from the higher end.
For healthy people, high protein intakes are safe. There's little added muscle benefit above ~2.2 g/kg, but no harm from moderately exceeding it.
Total daily intake matters most. That said, spreading protein across 3–5 meals of 0.4 g/kg each modestly improves muscle-protein synthesis versus one or two large servings.