Protein - Everything you need to know
You may heard a lot that people don’t eat enough protein, especially vegans but why proteins are so important and how much you should actually consume?
I collected some data and briefly summarised some key information on the role of protein, muscle building, daily protein requirements and if there is best time to have your post workout protein meal/shake.
1. Role of protein
2. Can your body store protein like it does fat or carbs?
3. Role of amino acids - some basics
4. How much protein do we need?
5. Best time to consume protein to maximise muscle growth
6. How to maximise muscle protein synthesis (MPS)?
7. How to workout to build muscles effectively?
1. Role of protein
The importance of protein in our life is reflected in the term itself: protein is derived from the Greek term protos, which means “first element." and protein is not only for bodybuilders :)
Protein makes up the vital organs, muscles, tissues and even some hormones like insulin and adrenaline, it is needed for tissue repair, neurotransmitters production and transporting nutrients. On average it compromises about 20% of body weight,
2. Can your body store protein like it does fat or carbs?
The thing is your body can’t store proteins as it does with carbohydrates or fats that’s why it’s so important to provide appropriate amounts each day. When this is neglected the body will break down vital tissues to supply amino acids that are missing and needed.
No matter if you are professional athlete or a person not exercising at all you need to meet your daily minimum protein requirement to maintain some of the body basic functions and processes as each day proteins in your body are broken down to amino acids and then rebuilt. If you exercise you are breaking down more protein in your muscles hence you need more protein to maintain your muscle mass.
Let’s make some math:
Building muscles = muscle breakdown < muscle protein synthesis
Loosing muscles = muscle breakdown > muscle protein synthesis
Maintaining muscles = muscle breakdown = muscle protein synthesis
3. Amino acids - basics
As just mentioned amino acids are basically building blocks of protein. Your body needs 20 amino acids to form hundred of different proteins in the body for various processes and functions.
12 amino acids can be made by the body (non-essential amino acids- NEAAs), the other 8 amino acids the body can’t synthesise and therefore they have to be provided with a diet, these are called essential amino acids (EAAs). Protein that you consume with the diet is broken down to amino acids so they can be reused for building muscles and other various processes.
4. How much protein do we need?
Here we need to consider few factors:
Activity level - The more you exercise, the more protein your body needs. The greater the intensity and the longer the duration of the workout the more protein is broken down and the more protein you need to consume to replenish it.
How much muscle you have. The more you have, the more amino acids your body needs to maintain your musculature
Age - The older you get, the more protein your body needs to maintain its muscle as your body is more resistant to hormones that stimulates MPS.
Hormones - Insulin growth hormone stimulates MPS, on the other hand elevated levels of cortisol reduces protein synthesis and accelerates the process where the body breaks down amino acids into glucose (gluconeogenesis).
More doesn’t mean better.
If you consume too much protein at once, the excess calories from protein will be converted into fat and excess amino acids will be exerted with urea. According to the recent studies upper protein limit per meal is 0.55g /kg of body weight.
Current guidelines for recommend daily protein intake :
0.7g/kg BW/day for both sedentary lifestyle and recreational low intensity exercisers
1 - 2g.kg BW/day for higher intensity trainings. Usually higher protein intake is recommended for resistance workout 1.2 - 2g/kg BW/day and slightly lower amount for endurance training 1 - 1.4g/kg BW/day.
These amounts are just average recommended reference values and should be adjusted according to individual needs lifestyle and age.
On average consuming 20-30g of protein post exercise is considered a good amount to maximise muscle repair. It also increases training adaptation and enhances performance for both strength and endurance athletes.
5. Best time to consume protein to maximise muscle growth.
There is no best time…
There are various theories in regard to when it is the best time to consume protein to maximise muscle protein synthesis (MPS) whether it should be before, after workout or before sleep. I personally prefer to have carb rich snack before workout and protein meal/shake after the training.
The post-exercise period is often considered critical, known as anabolic window - the time when amino acids are used most effectively to repair muscle tissues. However
Consuming protein within 1h after work out is critical if:
you trained in a fasted state (by fasted state we refer to the situation when your body finishes digesting the food - it may take 3-6h and it really depends on the meal).
you didn’t have any protein rich meal/snack/shake before training
you trained for prolonged period of time or your training was intense and certain amino acids are needed to repair muscle tissues. By prolonged period of time we refer usually to training for more than >1.5h.
On the other hand If you consumed protein before training your body probably still has some amino acids in the pool to repair muscles hence refuelling straight after workout is not so urgently needed comparing to the training in a fasted state i.e
Resistance training stimulates MPS up to 72h, hence what really matters is regular protein intake spread out through the day.
Measuring MPS is quite complex and there are many studies with no clear evidence weather it’s purely timing or other factors contributing to maximising MPS like total protein intake, cortisol levels, intensity and type of the exercises, pre workout snacks/meals or even genetics!
Regardless of this we should keep in mind the more muscle is broken down the more amino acids you will need to repair muscle tissues and providing right amount of protein on daily basis is the key.
6. How to maximise muscle protein synthesis?
Speaking of MPS there are few factors that may improve muscle repair, growth and strength : nutrition and exercise.
Spread protein intake throughout the day. 20-30g is average recommended amount per meal/serving to maximise MPS. Consuming more than 30g in one meal will not add much further benefits.
Leucine - is on of the branched-chain amino acids (BCAA) that is thought to be most potent at stimulating MPS. 20-30g protein serving containing all essential amino acids including around 3g of Leucine showed to be most beneficial.
Protein source - animal protein is usually higher in essential amino acids however combination of plant proteins like pea protein, brown rice protein or hemp gives very similar amino acid profile to i.e. whey protein and is a good substitute for vegetarians and vegans. Plant proteins are considered to be easier to digest, allergen free, higher in fibre and better for people with lactose intolerance. Pea protein is also high in glutamic acid comparing to whey. Glutamic acid converts to glutamate which is important neurotransmitter (affecting mood, memory). Glutamic acid also has detoxifying properties in muscle cells which is important when you exercise as working out increases levels of ammonia and lactic acid which slow downs recovery
Vitamin & Minerals: muscle growth and repair happens at the cellular level and it depends on a variety of vitamins and minerals, especially vitamins B, D, A and C. Briefly speaking, protein is essential for building muscles but including essential vitamins & minerals to your diet is a great addition to maximise MPS.
Omega 3: recent human studies shown that omega 3 fatty acids boosts muscle growth and recovery due to anti - inflammatory properties but still more evidence is needed. Omega 3 may also reduce heart rate and oxygen demand during exercise without decrease in performance which means less energy used.
7. How to work out to build muscles effectively?
The most effective type of the workout to stimulate MPS is resistance training as it makes muscles more sensitive to amino acids uptake and as mentioned earlier amino acids are the build blocks of you muscles. Work out routine also plays quite important role in MPS.
Number of sets - multiple sets are better than single set when we want to improve MPS. There is some scientific evidence that 10 sets a week are superior for muscle growth. It can be spread across the week, i.e 5 sets twice a week for particular muscle group.
Training status - the more trained you are the MPS response become shorter, which means to sustain that state you need to increase either frequency or volume/intensity of trainings.
Weight - any amount of weight as long as you train till muscular fatigue, you build your strength/stamina on the last reps when you think you can't push more - no pain no gain:) Train hard but avoid extreme overtraining - in other word know your limits.
Reps per set - on average 6-12 reps are recommended for optimal muscle growth.
Rest between sets - increased rests between sets increases larger post work out MPS compared to short rest period. At least 2 min rests is generally recommended.
Training frequency - training each muscle group at least twice a week is common practice for optimal muscle growth
If your goal is not only to repair and strengthen muscles but also muscle mass gains resistance training in combination with appropriate protein intake and daily calorie maintenance level is crucial.
For those who train on regular basis the right diet and providing appropriate amounts of the proteins and other nutrients is the key.
Hope you enjoyed the reading! In the next post I will go more into detail on the role of particular amino acids and comparing plant protein vs animal protein :) If you like the post please share or comment below :)
Here are some interesting studies if you would like to deep dive more into science:
1. How much protein can the body use in a single meal for muscle-building? Implications for daily protein distribution:
2.Beyond the zone: protein needs of active individuals.
3.The recommended dietary allowance for protein may not be adequate for older people to maintain skeletal muscle.
4.The hormonal control of protein metabolism
5.Nutrient timing revisited: is there a post-exercise anabolic window?
6.Protein timing and its effects on muscular hypertrophy and strength in individuals engaged in weight-training
7.Muscle protein synthesis in response to nutrition and exercise