MyGymCalcWhy protein comes first
Protein is the only macronutrient your body cannot store for later. Muscle repair, enzyme production and immune function all draw from what you ate today, which is why intake is measured per day, not per meal.
For lifters, protein does two jobs: it provides the raw material to repair the muscle broken down in training, and it protects that muscle when calories are low. That second job is why the target rises during a cut even though total food drops.
How the range is calculated
The calculator multiplies your body weight by a target range of grams per kilogram, drawn from the positions of the International Society of Sports Nutrition and the Journal of the International Society of Sports Nutrition:
- Goal: cutting needs the most (2.0–2.6 g/kg) because a deficit raises the risk of losing muscle; maintaining sits in the middle; bulking needs slightly less because energy is abundant.
- Training level: beginners respond to the low end of the range, while advanced trainees with more muscle mass benefit from the top end.
The output is a range rather than a single number because that is the truth of the research: there is a wide band of effective intakes, and the edges differ by body weight, training age and how aggressive the diet is.
How to use your result
Aim for the middle of the range first and treat the ends as adjustable. 80 kg at 1.8–2.2 g/kg means 144–176 g per day — pick roughly 160 g, hold it for two weeks and see how recovery and performance respond.
Split it across three to five meals, about 0.4 g/kg each, and anchor every meal with a solid protein source: chicken, lean beef, fish, eggs, Greek yoghurt or whey. Track it the same way every day for a week so the number on the label and the number on the scale start agreeing with each other.
Protein stays constant even when calories move. Adjust carbs and fat around it, never the other way round.