Protein, fats, carbs: how to set macros for your training goals

Calories matter — but they’re only half the story. Two people can eat exactly the same number of calories each day and get completely different results if their macronutrient breakdown looks different. Protein, fats, and carbohydrates are the three pillars of any effective nutrition plan. Understanding how much of each you need allows you not only to manage your weight, but also to support your training performance, recovery, and overall well-being. In this article, I’ll walk you through how to set up your macros step by step — no unnecessary complications, just concrete numbers and real examples.

Protein — the foundation of every nutrition plan

Protein serves functions in the body that no other macronutrient can replace. It’s responsible for rebuilding and growing muscle tissue, producing enzymes and hormones, and supporting the immune system. If you train regularly — whether your goal is fat loss, muscle building, or maintaining your current shape — protein should be your top priority.

The International Society of Sports Nutrition (ISSN) recommends consuming 1.6–2.2 g of protein per kilogram of body weight daily for physically active individuals. This range has been repeatedly validated in research for maintaining and building muscle mass. For an 80 kg person, that translates to 128–176 g of protein per day.

It’s worth knowing that protein has the highest thermic effect of all macronutrients — the so-called TEF (thermic effect of food) for protein is 20–30%. This means your body uses 20–30% of the energy from protein just to digest and absorb it. By comparison, TEF for carbohydrates is 5–10%, and for fats only 0–3%. This is one reason why high-protein diets support fat loss — even at the same caloric balance.

Protein is also the most satiating macronutrient. Research published in the American Journal of Clinical Nutrition shows that increasing protein intake to 25–30% of calories significantly reduces hunger and decreases spontaneous caloric intake. If you run a training studio and advise clients on nutrition, this is an argument that resonates with everyone.

Fats — not the enemy, but an ally

For years, fats were demonized as the main cause of weight gain. Today we know that it’s a caloric surplus — regardless of the source — that leads to fat accumulation. Fats themselves serve essential functions without which your body cannot function properly.

Fats are responsible for producing steroid hormones, including testosterone and estrogen. Consuming too little fat — below 20% of daily caloric needs — can lead to hormonal imbalances, reduced libido, mood deterioration, and concentration problems. This is particularly relevant for those who train intensely, where the demand for hormonal recovery is higher.

The minimum safe fat intake for active individuals is 0.8–1 g per kilogram of body weight. For an 80 kg person, that’s 64–80 g of fat daily, which translates to 576–720 kcal (1 g of fat = 9 kcal).

Omega-3 fatty acids play a particularly important role, demonstrating anti-inflammatory effects and supporting post-workout recovery. You’ll find them in fatty fish (salmon, mackerel, sardines), flaxseed, and walnuts. Fats are also essential for absorbing fat-soluble vitamins — A, D, E, and K. Without adequate fat in your diet, supplementing these vitamins becomes pointless.

Carbohydrates — fuel for training

Carbohydrates are the most flexible macronutrient in your diet. Once you’ve established the right amount of protein and fat, you fill the remaining calories with carbs. They’re the primary energy source during training — especially during moderate- to high-intensity exercise.

Muscle glycogen — the stored form of carbohydrates in your muscles — is the fuel your body taps into first during strength and interval training. Low glycogen levels directly translate to decreased endurance, poorer training outcomes, and slower recovery. Research published in the Journal of Sports Sciences confirms that adequate carbohydrate intake before and after training improves both performance and glycogen replenishment.

The distinction between “simple” and “complex” carbohydrates matters less than total daily intake. Of course, fiber-rich foods (grains, brown rice, vegetables, fruits) have an edge in terms of satiety and nutritional value. But if your total carbohydrate intake matches your activity level and the rest of your diet is balanced — the source of carbs is of secondary importance.

Carbohydrates also affect mood. Carb consumption stimulates serotonin production — the neurotransmitter responsible for feelings of calm and well-being. Extremely low-carb diets can lead to irritability, sleep problems, and decreased training motivation. This is worth sharing with clients who want to eliminate carbs from their menu at all costs.

How to calculate your macros step by step — an example

Let’s get practical. Consider this example: a male, 80 kg, caloric target of 2,400 kcal per day, in a fat loss phase.

Step 1: Protein

During a cut, we use the higher end of the range: 2 g/kg of body weight. For 80 kg, that’s 160 g of protein daily. Converting to calories: 160 g × 4 kcal = 640 kcal from protein.

Step 2: Fats

We set fat at 1 g/kg of body weight. For 80 kg, that’s 80 g of fat daily. Converting: 80 g × 9 kcal = 720 kcal from fat.

Step 3: Carbohydrates

Subtract protein and fat calories from the caloric target: 2,400 – 640 – 720 = 1,040 kcal. Divide by 4 kcal/g: 1,040 ÷ 4 = 260 g of carbohydrates.

Macro summary for this example:

• Protein: 160 g (640 kcal — 27% of calories)
• Fats: 80 g (720 kcal — 30% of calories)
• Carbohydrates: 260 g (1,040 kcal — 43% of calories)

These values don’t need to be followed down to the gram. A range of ±5–10 g in each macronutrient is perfectly normal. Consistency over the long term matters more than daily perfection.

How to adjust macros to your goal

Your macronutrient distribution should match your current training goal. Here are general guidelines for the three most common scenarios:

Fat loss

• Protein: 1.8–2.2 g/kg — higher intake protects muscle mass during a caloric deficit
• Fats: 0.8–1 g/kg — don’t drop below 20% of calories to avoid disrupting hormonal balance
• Carbohydrates: remaining available calories — reduced but sufficient to sustain training

Muscle building

• Protein: 1.6–2.0 g/kg — sufficient to support muscle protein synthesis
• Fats: 0.8–1.2 g/kg — adequate for hormonal function
• Carbohydrates: highest share — extra energy supports training intensity and recovery

Maintenance

• Protein: 1.6–1.8 g/kg — sufficient to maintain muscle mass
• Fats: 1–1.2 g/kg — a comfortable level supporting overall health
• Carbohydrates: moderate share — adjusted to activity level

Remember, these are starting points. Every body responds differently, and optimal ratios may require individual adjustments based on tracking your progress.

A meta-analysis published in the British Journal of Sports Medicine (2018) found that protein intake of at least 1.6 g/kg of body weight per day is critical for preserving muscle mass during a caloric deficit. Individuals meeting this threshold lost significantly less muscle compared to groups with lower protein intake — even at an identical caloric deficit.

Summary

Setting your macros doesn’t have to be complicated. Start with protein (1.6–2.2 g/kg), establish a fat minimum (0.8–1 g/kg), and fill the remaining calories with carbohydrates. This approach works whether you’re cutting, bulking, or in a maintenance phase.

If you haven’t been tracking macros until now, start with simple tracking for 2–3 weeks. Apps like MyFitnessPal or Fitatu make it easy to log meals and see how your habits look in numbers. After that period, you’ll have data that allows you to make informed adjustments.

Don’t look for the perfect plan — look for one you can actually stick with. Consistency with a sensible approach always beats perfection that lasts a week. If you want to learn more about building a diet tailored to your goals, check out the EloByku blog — you’ll find more articles to help you organize your nutrition knowledge.