What "Macros" Actually Means
Macros is short for macronutrients — the three main categories of nutrients your body uses for energy and function: protein, carbohydrates, and fat. Every food you eat contains some combination of these three. Calories come from macros. Macros come from food. That's the whole system.
You may also see alcohol listed as a fourth macronutrient (it provides 7 calories per gram), but it has no nutritional function worth optimising for, so most practical nutrition frameworks treat it separately.
Understanding macros matters because not all calories are equal — not in terms of what they do to your body. 200 calories from chicken breast does something different to your muscles, hormones, and satiety than 200 calories from pure sugar. The ratio and type of macros you eat shapes your body composition, your energy levels during training, and your ability to recover between sessions.
Protein: The Building Block
Protein provides 4 calories per gram and is the only macronutrient that directly builds and repairs muscle tissue. Amino acids — the compounds that make up dietary protein — are used by your body to synthesise new muscle proteins after training. Without adequate protein, the training stimulus is there, but the raw material to respond to it isn't.
For gym-goers, protein is the most important macro to get right. The research on protein requirements for people who lift is consistent: somewhere between 1.6–2.2g of protein per kilogram of bodyweight per day is optimal for muscle growth and retention. For a 80kg person, that's roughly 130–175g of protein daily.
Good protein sources for gym-goers:
- Chicken breast — around 31g protein per 100g cooked
- Greek yoghurt — 10g per 100g (fat-free varieties hit 17–18g)
- Eggs — 6g per whole egg, whites are almost pure protein
- Salmon — 25g per 100g plus omega-3 fats
- Lean beef mince — 26g per 100g (5% fat)
- Cottage cheese — 11–13g per 100g, slow-digesting casein
Plant-based sources (beans, lentils, tofu, tempeh, edamame) work well but typically require more food volume to hit the same protein numbers, and the amino acid profiles are less complete — combining sources addresses this.
Protein is also the most satiating macronutrient. Higher protein intakes are consistently associated with better appetite control, which matters whether you're trying to lose fat or maintain weight during a muscle-building phase.
Carbohydrates: The Performance Fuel
Carbohydrates provide 4 calories per gram. They're your body's preferred energy source for high-intensity activity — which is exactly what weight training is. When you lift weights, your muscles run primarily on glycogen, a stored form of carbohydrate. Deplete glycogen and performance drops: weights feel heavier, reps drop, focus fades.
This is why low-carb diets can impair gym performance. Fat can fuel long, slow aerobic activity, but the explosive, anaerobic effort of a working set of squats runs on carbohydrate. This isn't a recommendation to eat unlimited carbs — it's a reason not to fear them.
The quality of carbohydrate sources matters:
Higher-quality carbs (prioritise these):
- Oats, rice, potatoes, sweet potatoes
- Whole grain bread, pasta, wraps
- Fruit
- Vegetables (technically carbohydrate but also fibre and micronutrients)
Lower-quality carbs (moderate):
- Refined sugar, white bread, processed foods
- These aren't forbidden, but they provide energy without the additional fibre, vitamins, and minerals that make higher-quality carbs worth the calories
Carb timing matters to some extent. Eating carbohydrates before and after training supports performance and recovery. Pre-workout carbs top up glycogen; post-workout carbs help replenish it and spike insulin to drive nutrients into muscle cells alongside protein.
Fat: The Essential Macro
Dietary fat provides 9 calories per gram — more than double protein and carbs — which is why high-fat foods are calorically dense. Fat is essential for hormone production (including testosterone and oestrogen), joint lubrication, absorption of fat-soluble vitamins (A, D, E, K), and brain function.
For gym-goers, fat is the macro most likely to be either over- or under-consumed. Eating too little fat over time can impair hormone production and reduce performance. Eating too much displaces calories that could go to protein and carbs.
A reasonable target for most people: 20–35% of total calories from fat. For a 2500-calorie diet, that's 55–95g of fat per day.
Fat types matter:
- Unsaturated fats (prioritise): olive oil, avocado, nuts, fatty fish, seeds
- Saturated fats (moderate): butter, cheese, fatty cuts of meat, coconut oil — fine in moderation, not in excess
- Trans fats (minimise): partially hydrogenated oils found in some processed foods — associated with cardiovascular risk, largely phased out but worth checking labels
Omega-3 fatty acids (found in salmon, mackerel, sardines, flaxseeds, walnuts) are particularly useful for gym-goers due to their anti-inflammatory properties and potential role in supporting muscle protein synthesis.
What Tracking Macros Actually Looks Like
Tracking macros means logging what you eat and checking that protein, carbs, and fat land within your targets — not just that total calories are in the right ballpark.
A simple framework for setting macro targets:
- Protein first. Set protein at 1.8–2g per kg of bodyweight. This is non-negotiable.
- Set calories. Based on your goal: maintenance, deficit (fat loss), or surplus (muscle building).
- Fill remaining calories with carbs and fat. A common split is 40% carbs / 30% protein / 30% fat, but this varies. More active people benefit from more carbs. People on lower-calorie cuts often shift fat lower and carbs higher to preserve training performance.
You don't need to be exact. Being within 10g of your protein target and within 100–150 calories overall is good enough for consistent results. Precision matters less than consistency.
Why Most Gym-Goers Should Track Macros (At Least Temporarily)
Most people dramatically underestimate how much they're eating — or overestimate it. Studies consistently show people's self-reported calorie intake is off by 30–50%, often in the wrong direction. Tracking, even for 4–8 weeks, builds a calibrated sense of what foods contain and how much of each macro you're actually eating.
You don't have to track forever. Many experienced lifters eventually reach a point where they intuitively eat close to their targets without logging. But the intuition is built on a foundation of actual data — not guesswork.
The practical benefits of macro tracking for gym-goers:
- You know whether you're getting enough protein. Most people who don't track chronically under-eat protein.
- You can troubleshoot. If you're not recovering, not gaining, or not losing fat despite "eating well," tracking reveals what's actually happening.
- You make intentional trade-offs. Knowing a specific meal is high-fat helps you adjust the rest of the day rather than blindly blowing your targets.
Macros vs Calories: Do You Need Both?
Calories determine whether you gain, maintain, or lose weight. Macros determine what the weight you're gaining or losing is made of.
You can lose weight eating nothing but processed food if calories are in deficit. You'll also lose a significant amount of muscle alongside fat, feel terrible, and perform poorly in the gym. Total calories control the scale; macros control body composition.
For gym-goers, both matter. Tracking only calories is a blunt instrument. Tracking macros gives you a sharper tool — you can set an energy target and also ensure protein is high enough to preserve muscle, carbs are sufficient to fuel performance, and fat isn't so low that hormones take a hit.
How Soma Handles Macro Tracking
Soma makes macro tracking friction-free. The AI calculates your protein, carb, and fat targets based on your bodyweight, training schedule, and goal (build muscle, lose fat, or maintain). You don't need to calculate anything manually.
Photo calorie tracking means you can log a meal by taking a photo — no barcode scanning, no searching a database for the exact brand of your oats. The AI estimates the macro breakdown from the image. It's not perfect, but it's accurate enough to make consistent tracking actually sustainable.
The nutrition side is also connected to your training. If Soma sees you're running high RPE across all your sessions, it knows your performance is suffering — and can check whether carb or calorie intake is a likely cause. Nutrition and training aren't two separate apps that don't talk to each other.
Download Soma free on the App Store and start tracking macros the easy way.