Macronutrients: Protein, the ‘building blocks’ of muscle

Off to the gym with no time to read? Here are the key points…

  1. Protein is an essential macronutrient, are made of up to 20 amino acids and are the ‘building blocks of muscle’.
  2. Having adequate protein intake is imperative in supporting your fitness and weight loss goals. Aim for between 1.2–2.0 g/kg bodyweight per day. Research supports >3.0 g/kg protein when in a fat loss phase.
  3. Consuming high protein meal post-workout and spreading the remainder of your protein evenly throughout the day increases muscle growth potential.

In last week’s article we spoke about the importance of understanding how much energy your body requires in relation to your personal fitness goal. Whilst this is perhaps the most important overarching element in aligning your nutrition to your fitness goal, understanding how to fill your energy needs with the right macronutrients (that is protein, carbohydrates and fats) is also fundamental. Over the next three weeks we will be exploring each macronutrient, including why you need them and how to determine how much you individually require. This week we will be focusing on protein.

Protein — What is it?

Protein is an essential macronutrient and is made up of 20 different amino acids. These are required within every cell in the body, from being used in enzymes to DNA. Perhaps mostimportantly for you in terms of your exercise routine and fitness goals is the fact that they are the building blocks of muscle.

Having adequate protein in your diet not only promotes muscle growth but when in a fat loss phase (the energy deficit discussed in last week’s article), high protein intake well above normal recommendations can help retain muscle and aid in fat loss when coupled with exercise. But does the amount, timing and type affect your muscle building and retention potential? The short answer is yes!

Here’s the long answer:

How much protein should I have daily?

While the general population recommendation is 0.8 g/kg of protein per day, those who regularly exercise need more protein to aid recovery and to build muscle in response to the stress of exercise. How much additional protein you may need is largely dependent on your own goals. For example, those performing endurance exercise need around 1.2–1.6 g/kg per day to aid muscular recovery and for energy supply. However, those performing strength/power exercises, i.e. weightlifting, need more at around 1.4–2.0 g/kg per day to aid in both muscular recovery and growth.

Based on recent studies, consuming a high protein diet during a fat loss phase (>3.0g/kg per day) is not only safe, but promotes both muscle retention and increases fat loss. This is primarily because of the ‘thermic effect’ of protein. The ‘thermic effect’ essentially means the breaking down and use of protein requires energy, allowing you to burn a few extra calories a day increasing your total daily energy expenditure.

When and how often should I eat protein?

You may have heard of the ’20-minute anabolic window’ for consuming protein after a workout to maximise muscle growth potential. Whilst this idea is popular, many studies suggest that the window for having protein after exercise is much longer, even up to 24-hours. However, it is generally agreed that the longer you wait after exercise, the less effective it becomes.

So, whilst you don’t need to rush to your shaker and get your protein mix like your life depends on it after a work our, getting your protein in as soon as is convenient is generally a good idea.

Outside of post-exercise protein, it is best to distribute protein throughout the because there is a limit as to how much your body can use in one sitting (around 25g to 40g protein per serving). As such, we recommend eating protein at these doses every 3 to 4-hours in the day to help maximise muscle growth when outside the gym.

Does the type of protein I eat matter?

There are a lot of protein supplement companies claiming you need protein powder to make any form of noticeable gains. The truth is getting your protein from whole food sources, which contain high essential amino acid content such as leucine, is your best bet. Check out the ‘protein quality pyramid’ below to see which sources are the best. The pyramid is based on the protein’s amino acid score and how ease of digestion.

Whilst whole food sources are the best choice to base your protein intake around, whey, casein and soy are still high-quality protein sources which should be used to supplement your whole food diet, but not replace it. It is important to remember that if you are vegetarian or vegan to vary your protein sources as many non-animal proteins do not contain all the essential amino acids your body needs.

It seems like there is a lot to consider when determining the amount of protein you need to support your fitness goals, but protein recommendations boil down to three main factors. Firstly, how much protein you need to fit your goals, then spreading your protein intake throughout the day (with an emphasis of having a high protein meal post-workout) and finally consuming whole food sources of high quality protein and supplementing when necessary.

Once you figure out how much protein you should be consuming per day, you can multiply this by 4 to give you your total calorie intake from protein (1g of protein = 4 calories). You can then subtract this from your total energy intake based on last week’s article to determine how many calories you have left for carbohydrates and fats.

Watch out for the next article where we will be looking at why carbohydrates are so important to fuel performance, and how much you should be consuming based on your goals. Until then, get to the gym!

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About the Author: Kaspar Iskjær is a London based Personal Trainer with an MA in Nutrition.


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