Calorie surplus and recomposition.

Half the people who land on a nutrition site need to eat less. The other half need to eat more — they want to build muscle, recover better, or fill out a frame that years of undereating or cardio have whittled down. If that is you, the question is not whether to eat a surplus, but how big, for how long, and which of the three approaches fits your situation.

The three approaches

Traditional bulk. Eat in a large surplus (20–30%+ above TDEE), train hard, accept that you will gain significant fat alongside muscle. When you have added enough mass, switch to a prolonged cut to strip the fat. This was the default bodybuilding approach for decades. It works — you will get bigger — but you will also spend a lot of time being heavier and softer than you want to be, and the subsequent cut is long and psychologically draining.

The main advantage of a traditional bulk is simplicity: you do not need to track closely, you never feel hungry, and your training performance is excellent because energy is abundant. The main disadvantage is that most of the weight you gain is fat, not muscle. For every kilogram of muscle gained, you typically add 2–3 kg of fat (or more if the surplus is excessive).

Lean bulk. Eat in a small, controlled surplus (5–15% above TDEE, roughly 200–500 kcal/day). Train with progressive overload. Track weight weekly and adjust calories so that weight gain stays within 0.25–0.5 kg per week for men, 0.12–0.25 kg per week for women. The fat-to-muscle gain ratio is much better: roughly 1:1 in a good lean bulk versus 2–3:1 in a traditional bulk.

The downside is that it requires more precision. You need to weigh yourself regularly, adjust calories monthly, and accept that visible progress is slow. But the payoff is that you spend less time cutting afterward and stay leaner year-round.

Recomposition. Eat at or slightly below maintenance while resistance training. The goal is to lose fat and build muscle simultaneously, without the scale moving much. Your weight stays roughly the same, but your body composition improves: measurements change, clothes fit differently, and the mirror gradually shifts.

Recomposition is real, but it is slow, and it does not work equally well for everyone (more on that below).

How big should the surplus be?

Muscle protein synthesis — the biological process of building new muscle tissue — has a ceiling. You cannot force faster growth by eating more than that ceiling allows. Extra calories beyond what your body can use for muscle growth are stored as fat. The practical implication: a modest surplus builds muscle at the same rate as a large one, with much less fat gain.

Using the McDonald model: a male beginner can gain roughly 9–11 kg of muscle in year one. That is about 0.75–0.9 kg per month. To support that rate, you need a surplus of roughly 200–400 kcal per day — far less than most people think. A 5–15% surplus above TDEE is the recommendation for a lean bulk.

For a man with a TDEE of 2,800 kcal, that is 2,940–3,220 kcal per day. For a woman with a TDEE of 2,000 kcal, that is 2,100–2,300 kcal per day. Monitor your weight weekly. If you are gaining faster than 0.5 kg per week (men) or 0.25 kg per week (women), reduce the surplus slightly — the excess is going to fat.

Realistic muscle gain rates

The McDonald model is the most widely cited framework. It assumes consistent training (3–5 days per week, progressive overload), adequate nutrition (surplus + sufficient protein), and normal hormone status.

• Year 1 (beginner): Men ~9–11 kg, Women ~4.5–5.5 kg
• Year 2 (intermediate): Men ~4.5–5.5 kg, Women ~2.25–2.75 kg
• Year 3 (intermediate-advanced): Men ~2–3 kg, Women ~1–1.5 kg
• Year 4+ (advanced): Men ~1–1.5 kg, Women ~0.5–0.75 kg

These numbers are upper-end estimates. Genetics, sleep quality, stress levels, age, and training programme quality all affect the actual outcome. Most men will not gain 11 kg of muscle in their first year. Most will gain 5–8 kg, which is still a dramatic transformation.

Women build muscle at roughly 50% of the male rate, primarily because of lower testosterone levels. This is not a disadvantage — it simply means expectations need to be calibrated accordingly. A woman who gains 3–4 kg of muscle in her first year has made excellent progress.

Recomposition: when it works and when it does not

Body recomposition — losing fat and gaining muscle simultaneously — is possible, but not for everyone.

Good candidates for recomposition:

• True beginners (first 6–12 months of resistance training). The "newbie gains" effect means you can build muscle at an accelerated rate even without a surplus.
• People returning to training after a break of 3+ months. Muscle memory (myonuclear retention) allows faster regrowth.
• People with high body fat (above 20% for men, above 30% for women). Your body has ample stored energy to fuel muscle growth without needing dietary surplus.
• People using performance-enhancing drugs (not a recommendation, but a reality that changes the biology).

Poor candidates for recomposition:

• Trained intermediates and advanced lifters at a normal body fat. The rate of possible muscle gain is too slow for recomposition to be measurable.
• People who are already lean (below 12% for men, below 20% for women). There is not enough stored fat to fuel muscle growth without dietary surplus.
• People who want visible results quickly. Recomposition is the slowest path.
• People over 50 without significant training history. The anabolic resistance of ageing makes surplus-fuelled training more effective than recomposition.

Macros for a surplus

Protein is still the priority. The same 1.6–2.2 g/kg recommendation from our macros guide applies, and arguably the lower end (1.6–1.8 g/kg) is sufficient during a surplus because you are not in an energy deficit and muscle protein breakdown is lower.

Notice the high carbohydrate intake. This is intentional. Carbs fuel training performance (glycogen), support recovery, and spare protein from being used as fuel. During a surplus phase, carbs are your friend.

Surplus in your 40s and 50s

Building muscle after 40 is absolutely possible, but two factors change.

Anabolic resistance. As you age, your muscles become less responsive to the anabolic (muscle-building) signal from both training and protein. The practical fix: increase protein slightly (2.0+ g/kg), ensure leucine-rich sources (dairy, eggs, meat), and consider distributing protein across 4 meals rather than 2–3.

Recovery. Connective tissue takes longer to repair. Joint stress accumulates faster. Training volume may need to be lower than in your 20s, with more recovery days. This does not mean lighter weights — it means smarter programming. Three well-designed training days per week will outperform five mediocre ones.

The surplus size does not need to change. A 5–15% surplus still works. The rate of muscle gain will be slower (closer to the Year 3–4 numbers in the McDonald model), but it is still meaningful. A 50-year-old man who gains 2 kg of muscle over a year has made a real difference to his metabolism, strength, bone density, and quality of life.

Why dirty bulks backfire

A dirty bulk (eating 30–50%+ above TDEE, often with no attention to food quality) is tempting because it is easy. You eat whatever you want, whenever you want, and the scale goes up satisfyingly fast.

Here is the maths on why it is a bad strategy for most people:

A man bulks for 6 months at a 1,000 kcal/day surplus. He gains 10 kg of bodyweight. Of that, approximately 2.5–3 kg is muscle (because you cannot force faster growth regardless of how much you eat) and 7–7.5 kg is fat.

He now needs to cut 7–7.5 kg of fat. At a 500 kcal/day deficit, that takes roughly 15–16 weeks. During that cut, he will likely lose 0.5–1 kg of the muscle he built, especially if protein is not prioritised. Net result after the full bulk-cut cycle: roughly 1.5–2.5 kg of net muscle gain, after 6 months of bulking plus 4 months of cutting — 10 months total.

Compare to a lean bulk over the same period: 10 months at a 300 kcal surplus, gaining 0.3–0.4 kg per week. Total weight gain: roughly 5–6 kg, of which 2.5–3 kg is muscle and 2.5–3 kg is fat. A brief 6–8 week mini-cut removes the fat. Net result: roughly the same muscle gain, but you spent 10 months looking and feeling better instead of 6 months bloated and 4 months dieting.

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