Good old protein, the gym goers best friend.
If you’re not consuming a gazillion grams a day and taking a dose within 49 seconds of each set, obvs within your anabolic window, do you even lift bro?!
The above sentence is clearly total guff. But unfortunately not an uncommon thought process seen throughout the online fitness world.
You have to bear in mind that protein supplementation is big business and companies will do all they can to make sure you buy as much of their product as you can afford.
This includes sponsoring online channels and websites to promote particular brands and supplementation ‘science’.
To this end much of the advice around protein supplementation, particularly regards how much you need, is often a little wonky (read over estimated) to say the least.
To help you cut through the nonsense we’ve set out a brief primer with research backed advice on protein intake that will help optimise your training and muscle building journey.
Read on for our protein primer for muscle growth.
Before we get started, keep in mind that while protein intake is important, doing the actual heavy lifting is what really builds strength and increases muscle size.
It shouldn’t need saying but don’t skip the gym and think you’ll still see gains by chugging a protein shake. You need to nail both your training and your nutrition for optimal gains.
Why is protein important for building muscle?
Dietary protein supplementation has been shown to significantly enhance changes in muscle strength and size during prolonged resistance exercise training (i.e lifting weight).
Protein is important as it contains amino acids, the building blocks used for muscle growth. This building occurs through what is known as muscle protein synthesis.
Put simply, muscle protein synthesis is the production (synthesis) of proteins by your body to repair and/or build muscle fibres that have been damaged.
This damage can be caused by resistance training and it is during the repairing stage that muscles can increase in size and strength. This means they are better able to cope with a repeat of the stress that caused the damage in the first place.
For your body to build muscle proteins it needs what are known as essential amino acids. These are amino acids that your body cannot produce on its own and therefore need to be obtained from the food you consume.
When you consume protein your body breaks it down into its component parts, the amino acids, and then rebuilds it into new proteins to meet your body’s requirements.
If you undertake resistance training to a sufficient level of ‘fatigue’, one of these requirements will be to rebuild your muscles to repair the damage from your workout.
How much protein do you need to build muscle?
So we know protein is an essential cornerstone of an optimal muscle building programme.
But how much protein should you consume per day to build lean muscle and maximise your gains?
Well, as with your overall total calorie intake, the amount of protein you need per day is often overstated.
This systematic review and meta analysis of the effects of protein supplementation on resistance training induced muscle gains concluded that 1.6g of protein per kg of bodyweight was sufficient for effective muscle growth, when combined with regular resistance training.
So if you weigh in at 80kg you want to be consuming approximately 128g of protein per day to maximum muscle growth.
That said, the 1.6g per kg target should not be viewed as an ironclad or universal limit beyond which protein intake will be wasted.
As the meta analysis also concludes, there is some evidence to support a higher intake of up to 2.2 g/kg/day.
Conversely you wouldn’t necessarily be worse off, muscle gain wise, from consuming slightly less than 1.6g per kg, provided you are undertaking regular resistance training.
It is best, therefore, to look at protein intake as a recommended range and consume between 1.6 – 2g per kg of bodyweight per day depending on your individual circumstances, training goals and routine.
E.g, as an experienced lifter trying to reduce body fat while maintaining as much lean muscle mass as possible, it may be sensible to consume the higher amount of protein in place of some of your carbohydrate and fats.
On the flip side, as a muscle building beginner you will be absolutely fine working at the 1.6g target.
It’s worth also noting that protein intake recommendations are usually based on lean body weight (total body weight minus body fat).
Thus, particularly at the start of your muscle building journey where you are likely carrying excess weight in the form of excess body fat, you’ll will see great results working at the lower end of the protein intake scale.
Also of note, the research suggests that age may impact protein intake requirements, with older trainees (40’s plus) being advised to aim towards the higher end of the range.
As with your general calorie count, don’t sweat being absolutely bang on the money with your daily protein intake.
In the real world it is impossible to be 100% accurate on the calorie and macro breakdown of everything you eat.
Just try to get as near as you can each day and over the weeks things will average out.
You can then use your weight, appearance and gym performance to tweak your diet accordingly.
How much protein should I consume in one meal?
Rather neatly, this follow up research by Schoenfeld and Aragon suggest simply splitting your daily protein intake across 4-5 meals.
So for an 80kg trainee looking to consume 1.6g – 2g of protein per kg of bodyweight, you’d be looking at approx 32-40g per meal, assuming 4 meals.
It is important to note that you want to be consuming your protein as part of a full, balanced meal. That is you want to be consuming your protein along with your other macronutrients (your carbs and fats).
You can consume smaller amounts of protein in isolation (i.e. 20-25g via a protein shake). But your body struggles to absorb and make use of much more than this without the addition of other macro and micronutrients.
Does protein intake timing matter?
It’s fair to say that the research on the importance of protein intake timing is mixed.
Some research does highlight potential advantages of protein intake immediately post exercise, while other evidence stresses the total daily amount is what really matters.
In our view there isn’t any compelling evidence to suggest there is a limited time frame for consuming protein post exercise for best results.
If you are getting your regular 4 – 5 meals each day, with 30-40g of protein in each, then you’ll be covering both your total intake and any potential need for post exercise intake simply though the fact you’ll be eating every couple of hours.
Having said that, there is certainly no drawback in consuming a protein shake post exercise. And if it helps you reach your daily total, all the better.
But bear in mind that if you are taking protein in isolation then 20-25g is about the most your body will effectively absorb for muscle growth.
So don’t take a double or triple shake serving to get to your daily total.
Can you have too much protein?
There is some limited research suggesting a high protein diet can lead to an increased risk of osteoporosis and the worsening of existing kidney problems.
It is fair to say, however, that there is much conflicting evidence on what constitutes ‘too much’ protein and many of the danger stories have focused more on very high red meat consumption.
While there isn’t clear evidence on what constitutes too much, it is generally viewed that up to 2-2.5g per kg of bodyweight poses little to no health risk.
But we are inclined to agree that it is a good idea to also pay attention to the type of protein in your diet and not just the amount.
For example, moderating consumption of red meat and increasing intake of protein sources such as poultry, fish and beans may be advisable.
Another consideration is that while there initially seems limited drawback to consuming more of your daily calories via a higher protein intake. If your protein intake is so high that it eats (pun fully intended) into your carbohydrate and fat allowance, which are both also essential, it may actually be detrimental to your training and muscle gain.
What are healthy sources of protein?
Lean animal proteins, such as chicken, turkey, beef, fish, eggs and dairy, are some of the most complete protein sources, meaning they provide your body with every essential amino acid your body cannot manufacture on its own.
For the vegans amongst you excellent sources of protein are nuts like almonds and pistachios (which have the added benefit of being high in calcium which is key for maintaining strong bones), all bean varieties (black, kidney etc.), pulses, legumes and leafy greens.
As noted above, you want to be consuming your protein as part of a full, balanced meal. That is you want to be consuming your protein along with other macronutrients (your carbs and fats).
Should I use protein shakes and supplements?
As with anything concerning your diet, you are generally better off consuming natural whole foods to reach both your total calories and macronutrient requirements.
That said, it can be tricky to hit your protein intake though turkey mince, salmon and leafy greens alone, especially if also trying to keep your fat intake down.
So using a protein shake/supplement to hit your daily intake target is totally fine. And whey protein, which is the most popular supplement, is a great source of protein as it contains the essential amino acids your body needs for muscle protein synthesis.
But be aware of what is in the mix you use and check the label for the amount of sugar and/or other ingredients you may want to keep in check.
As previously stressed, bear in mind that your body struggles to absorb and utilise more than 20-25g of protein in one serving without other macronutrients (your carbs and fats).
So you shouldn’t rely on a double or triple shake in one sitting to get to your daily total.
Final thoughts
Multiple studies have demonstrated the importance and benefits of adequate protein consumption to support resistance training and muscle growth.
With the help of our primer you hopefully now understand why it’s important and how much you really need.
Stick to the key points below and, with consistent hard work in the gym, you’ll be providing your body with the protein it needs to fuel your lean muscle growth:
- Protein is a vital component of your nutrition and adequate consumption is important to build lean muscle.
- Aim to consume 1.6 – 2.2g of protein per kg of bodyweight per day. The vast majority of trainees will be fine at the lower end, very lean lifters, and older lifters should experiment at the higher end.
- Always try to consume your protein along with other macronutrients (i.e. fats and carbohydrates) as part of a full meal. This will allow your body to better absorb and utilise higher amounts of protein.
- Split your protein intake across 4 or 5 meals, aiming for around 30-40g per meal.
- Your body can only absorb and make use of approximately 20-25g of protein if taken in isolation. So don’t rely on multiple protein shakes in one sitting to hit your daily target.
- Your overall daily protein intake matters more than the actual timing of when you consume it. It isn’t essential that you consume protein immediately post workout, but it is advisable for older trainees (the over 40’s).
