How Much Protein Do You Really Need to Build Lean Muscle?

Why Is Protein Important for Building Muscle?

Protein is made up of amino acids, often described as the building blocks
of protein in the body.

When you perform resistance exercise — whether that’s weight training,
CrossFit, HYROX or strength training — it creates a stimulus for your
muscles to adapt.

Both resistance exercise and consuming protein stimulate
muscle protein synthesis (MPS), the process through which
the body produces new muscle proteins (Jäger et al., 2017).

Think of training as sending your body the message that it needs to become
stronger. Protein provides some of the nutritional building blocks required
to help it respond to that message.

This is why simply eating more protein without training isn’t a shortcut to
building muscle. The combination of

progressive resistance training, adequate protein intake, sufficient
overall nutrition and recovery

is what matters.

How Much Protein Do You Need to Build Lean Muscle?

The standard protein requirement for the general population shouldn’t
necessarily be viewed as the optimal amount for someone who trains regularly
and wants to build muscle.

The International Society of Sports Nutrition recommends approximately
1.4–2.0 grams of protein per kilogram of body weight per day
for most exercising individuals looking to build or maintain muscle
(Jäger et al., 2017).

A major systematic review and meta-analysis by Morton et al. (2018),
involving 49 studies and 1,863 participants, found that protein
supplementation enhanced gains in muscle mass and strength during prolonged
resistance training.

Their analysis found that increases in fat-free mass tended to plateau at a
total daily protein intake of approximately
1.6 g/kg/day, although individual requirements can vary.

What Does 1.6 g/kg Look Like?

These numbers aren’t a rule that everyone needs to follow exactly. Your
requirements can vary according to your training volume, age, overall
energy intake, goals and individual circumstances.

Protein Isn’t Just About Your Post-Workout Shake

One of the most persistent ideas in fitness is the so-called
“anabolic window”: the belief that you need to consume
protein immediately after finishing your workout or you’ve somehow missed
your opportunity to build muscle.

The reality is more nuanced.

Protein around your training session can certainly be useful, but your
total protein intake across the entire day is extremely
important.

Research reviewed by the International Society of Sports Nutrition suggests
that consuming high-quality protein in servings of roughly
20–40 g, or approximately
0.25 g/kg body weight, can effectively stimulate muscle
protein synthesis (Jäger et al., 2017).

Research discussed by sports nutrition scientist Professor Asker Jeukendrup
also highlights the importance of looking beyond total daily intake and
considering how protein is distributed across meals (Jeukendrup, 2016).

Rather than eating very little protein for most of the day followed by one
enormous protein-heavy dinner, it can therefore be practical to include
quality protein sources across several meals.

Breakfast, lunch, dinner and snacks all represent opportunities to
contribute towards your daily protein intake.

What Are the Best Sources of Protein?

You don’t have to live on chicken breasts and protein shakes.

There are plenty of protein-rich foods that can contribute towards your
daily intake, including:

• Eggs
• Chicken
• Lean beef
• Fish
• Milk and yoghurt
• Cottage cheese
• Legumes and pulses
• Tofu and other soy foods
• Whey protein

Different protein sources have different amino-acid profiles and rates of
digestion, which is one reason variety within your diet is useful.

Whey protein is particularly popular among active people because it provides
high-quality protein in a convenient form. But it should be thought of as
exactly that:
a convenient way to supplement your diet, rather than a
replacement for a balanced diet.

Do You Actually Need a Protein Shake?

No.

You can absolutely meet your protein requirements through food.

But there’s a difference between possible and practical.

If you need 120–150 g of protein per day, for example, consistently reaching
that amount through normal meals can sometimes be difficult — particularly
when you’re working, travelling, training or simply don’t feel like
preparing another protein-rich meal.

A whey protein shake can make hitting your daily protein target
significantly more convenient.

A quality whey protein can be useful after training, with breakfast, between
meals or at other times when getting a protein-rich whole-food meal isn’t
practical.

Protein Alone Won’t Build Muscle

This is an important point.

You cannot out-supplement poor training, inadequate recovery or an
unbalanced diet.

The research shows that resistance training itself is the primary stimulus
for increases in muscle mass and strength. Protein helps support and
optimise the body’s adaptation to that training (Morton et al., 2018).