How much protein do you need for strength?

Protein is the one macronutrient you can’t afford to get wrong when training for strength. As covered in our nutrition guide for strength training, getting enough protein is one of the most impactful dietary choices you can make. Get enough and your muscles have the raw material to repair and grow. Get too little and no amount of perfect programming will save your progress.

The good news: the science on protein for strength is well-established. You don’t need to guess. Here’s what the research actually says.

How much protein you need

The research consensus

The most comprehensive meta-analysis on protein and resistance training was published by Morton et al. in the British Journal of Sports Medicine in 2018. They analyzed 49 studies with 1,863 participants and found:

• Protein supplementation significantly increased muscle strength and size during resistance training
• The optimal intake was approximately 1.6g per kg of bodyweight per day
• Benefits plateaued around 2.2g per kg of bodyweight per day
• Intakes above 2.2g/kg showed no additional benefit for muscle growth

This gives you a clear target range: 1.6-2.2g of protein per kg of bodyweight per day.

What that looks like in practice

Bodyweight	Minimum (1.6g/kg)	Optimal (2.0g/kg)	Upper range (2.2g/kg)
60 kg	96g	120g	132g
70 kg	112g	140g	154g
80 kg	128g	160g	176g
90 kg	144g	180g	198g
100 kg	160g	200g	220g

For simplicity, aim for 2g per kg and you’re covered. That’s an 80kg person eating 160g of protein daily.

If you’re significantly overweight, calculate based on your goal bodyweight or lean body mass rather than total bodyweight. A 120kg person at 35% body fat doesn’t need 240g of protein - calculating from an 85-90kg goal weight (170-180g) is more appropriate.

Does more help?

Going above 2.2g/kg won’t build more muscle, but it won’t hurt you either. The excess protein is simply used for energy or excreted.

Some lifters find that higher protein intake helps with satiety during a cut, which is a valid reason to eat more than the research-optimal amount. But for pure muscle-building purposes, the 1.6-2.2g/kg range captures the benefit.

Protein timing: what actually matters

Total daily intake dominates

The most important protein variable is how much you eat per day. A 2013 meta-analysis by Schoenfeld et al. in the Journal of the International Society of Sports Nutrition found that when total daily protein was equated, timing effects largely disappeared.

In other words: 160g of protein spread across four meals builds roughly the same muscle as 160g distributed differently, as long as the daily total stays the same.

But distribution helps slightly

While total intake is king, there’s a modest benefit to spreading protein across meals rather than eating it all at once.

Research suggests that 20-40g of protein per meal optimally stimulates muscle protein synthesis (MPS). Eating 80g in one sitting does trigger MPS, but not twice as much as 40g. The surplus is oxidized for energy rather than used for muscle building.

Practical recommendation: Eat 3-5 meals with 25-50g of protein each. This optimizes MPS throughout the day while being realistic for most people’s schedules.

The anabolic window

The “you must eat protein within 30 minutes of training” idea has been thoroughly debunked. A 2013 meta-analysis found that the supposed post-workout window was largely an artifact of studies where participants trained fasted.

If you ate a meal 2-3 hours before training, your body still has amino acids available during and after the workout. Having protein within a few hours of training is sensible. Rushing to chug a shake within 30 minutes isn’t necessary.

Simple rule: Eat a protein-containing meal sometime before training and sometime after. Don’t stress about minutes.

Protein sources: quality matters

Not all protein is created equal. Two factors matter: amino acid profile and bioavailability.

Complete vs incomplete proteins

Your muscles need all nine essential amino acids to build new tissue. A complete protein provides all nine in adequate amounts. An incomplete protein is low in one or more.

Complete protein sources:

• Meat (beef, chicken, pork, lamb, turkey)
• Fish and seafood (salmon, tuna, cod, shrimp)
• Eggs (whole or whites)
• Dairy (milk, Greek yogurt, cottage cheese, whey, casein)
• Soy (tofu, tempeh, edamame)
• Quinoa

Incomplete protein sources (need combining):

• Legumes (beans, lentils, chickpeas) - low in methionine
• Grains (rice, wheat, oats) - low in lysine
• Nuts and seeds - low in lysine
• Most vegetables - low amounts overall

Combining incomplete proteins (rice + beans, hummus + pita) provides a complete amino acid profile. You don’t need to combine them in the same meal - the same day is fine.

Bioavailability

Your body doesn’t absorb all protein equally. The Digestible Indispensable Amino Acid Score (DIAAS) measures how much protein your body actually uses:

Source	DIAAS Score	Practical meaning
Whey protein	1.09	Excellent - nearly all absorbed
Eggs	1.13	Excellent
Chicken breast	1.08	Excellent
Milk	1.14	Excellent
Beef	1.10	Excellent
Soy protein	0.90	Good
Pea protein	0.82	Good
Rice protein	0.37	Low - needs combining
Wheat protein	0.40	Low - needs combining

This doesn’t mean plant proteins are useless. It means plant-based eaters should aim for the higher end of the protein range (2.0-2.2g/kg) to compensate for lower bioavailability, and should combine sources for complete amino acid profiles.

Best protein sources per calorie

If you’re watching calories while hitting protein targets, some sources are more efficient:

High protein, low calorie:

• Chicken breast: 31g protein per 100g, 165 calories
• Greek yogurt (0% fat): 10g protein per 100g, 59 calories
• Egg whites: 11g protein per 100g, 52 calories
• Whey protein: 25g protein per scoop, ~120 calories
• Cod/tilapia: 26g protein per 100g, 105 calories

High protein, moderate calorie:

• Salmon: 25g protein per 100g, 208 calories
• Lean beef: 26g protein per 100g, 250 calories
• Whole eggs: 13g protein per 100g, 155 calories
• Cottage cheese: 11g protein per 100g, 98 calories

For a complete breakdown of nutrition for strength training, read the full nutrition guide for 5x5.

Protein supplements: when they make sense

Supplements aren’t magic. They’re convenient protein sources. That’s it.

Whey protein

The most researched protein supplement. Fast-absorbing, complete amino acid profile, high in leucine (the amino acid that triggers MPS most effectively).

Use when: You can’t hit daily protein targets with whole food, or you want a convenient post-training option.

Types:

• Whey concentrate: 70-80% protein. Cheapest. Contains some lactose.
• Whey isolate: 90%+ protein. Less lactose. Better for lactose-intolerant people.
• Whey hydrolysate: Pre-digested. Fastest absorption. Most expensive. Minimal practical benefit over isolate.

Concentrate is fine for most people. Save your money.

Casein protein

Slow-digesting dairy protein. Often recommended before bed for sustained amino acid release during sleep.

The research on casein timing is modest. If you’re hitting daily protein targets, casein before bed provides minimal additional benefit. If you like it, it’s fine. It’s not a game-changer.

Plant-based protein powder

Pea protein and rice protein are the most common. Individually, each has an incomplete amino acid profile. Combined (most plant-based powders blend them), they’re reasonably complete.

Plant-based powders work. They’re slightly less bioavailable than whey, so you might need 10-20% more to get the same effect. Not a dealbreaker.

Creatine

Not a protein, but worth mentioning here because it’s the most effective legal supplement for strength. 3-5g of creatine monohydrate daily increases strength, power, and muscle mass. It’s been studied extensively for over 30 years with no significant side effects in healthy adults.

If you take one supplement, make it creatine, not protein powder.

Common protein myths debunked

Myth: you can only absorb 30g of protein per meal

This refuses to die. The reality: your body can absorb virtually all the protein you eat. There’s no magic cutoff where extra protein gets wasted.

What’s true is that muscle protein synthesis has a per-meal ceiling of roughly 20-40g. Eating 60g in one meal stimulates MPS about as much as 40g, but the extra 20g is still absorbed and used - just for energy production and other bodily functions rather than direct muscle building.

A 2018 study by Schoenfeld and Aragon in the Journal of the International Society of Sports Nutrition concluded that the body can use well over 30g per meal for muscle-related processes, especially in the context of a mixed meal eaten post-training.

Eating your entire daily protein in one meal is suboptimal for MPS but not wasteful. Spreading it across meals is better, but don’t stress if one meal is larger than others.

Myth: high protein damages your kidneys

A persistent myth with no evidence in healthy individuals. A 2016 meta-analysis in the Journal of Nutrition reviewed studies with protein intakes up to 3.5g/kg/day and found no adverse effects on kidney function.

If you have pre-existing kidney disease, follow your doctor’s guidance. For everyone else - including strength athletes eating 2g/kg or more - kidney damage from protein is not a concern.

Myth: you need protein immediately after training

The post-workout “anabolic window” was exaggerated by supplement marketing. As discussed above, having protein within a few hours of training is reasonable. Rushing to drink a shake in the locker room isn’t necessary if you ate a meal before training.

Myth: plant protein can’t build muscle

Plant protein can absolutely build muscle. It’s less efficient per gram (lower bioavailability, incomplete amino acid profiles), which means plant-based athletes need to eat more total protein and combine sources carefully. But the end result - muscle growth and strength gains - is achievable.

A 2021 study in Sports Medicine found no significant difference in muscle growth between animal and plant protein groups when total protein and essential amino acids were matched.

Putting it into practice

Step 1: Calculate your target

Multiply your bodyweight in kg by 2. That’s your daily protein target in grams. Simple.

80kg person = 160g protein per day.

Step 2: Build meals around protein

Plan each meal starting with the protein source. Everything else fills in around it.

Example day for 160g protein:

• Breakfast: 3 eggs + 2 egg whites, toast (25g protein)
• Lunch: Chicken breast with rice and vegetables (40g protein)
• Snack: Greek yogurt with almonds (20g protein)
• Dinner: Salmon with potatoes and salad (35g protein)
• Evening: Cottage cheese or protein shake (25-30g protein)
• Snack: Handful of jerky or cheese (15g protein)

Total: ~160-165g protein

Step 3: Track for two weeks

Most people overestimate their protein intake. Track everything for two weeks using a food app. You’ll likely discover you’re eating less than you think.

After two weeks, you’ll have a realistic picture and can adjust portions accordingly.

Step 4: Supplement only if needed

If you consistently fall 30-40g short of your target despite whole food effort, add a protein shake. One scoop of whey with water or milk closes the gap.

Don’t default to shakes. Whole food provides micronutrients, fiber, and satiety that powder doesn’t. Use supplements to supplement, not replace.

The bottom line

Protein for strength training isn’t complicated. Eat 1.6-2.2g per kg of bodyweight daily. Spread it across 3-5 meals. Prioritize complete protein sources. Don’t obsess over timing.

This single nutritional habit - eating enough protein consistently - has more impact on your strength gains than any supplement, timing strategy, or macro manipulation.

Get your protein right, train with progressive overload, sleep well, and results follow. For the full picture on calories, carbs, fats, and meal planning, see our complete nutrition guide.

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