For years the accepted dogma was that 1g per lbs of body weight was the minimum protein intake an athlete or bodybuilder should consider in order to grow. This was idea was perpetuated by supplement companies saying that the more you train and the harder you train you should think about upping your protein intake to 1.5g/lbs or even 2g/lbs! How true is that though?
We know that when you train you induce an injury response in your muscles. The more frequent the injury response, the more you grow or the more you adapt.
What do you need in order for the muscles to grow? Well you need the three basic macronutrients – protein, carbohydrates and fat. Of course there are other micronutrients you require for various reactions in your body but for the most part we can assume they’ll be contained in the wholefood we eat.
People have been repeatedly spouting (and I’m guilty of this) that if you go below 1g per lbs of body weight you won’t maintain the musculature you have. In fact, there’s clinical evidence that shows that going below 1g allows you to maintain muscle and even GROW.
Clinical evidence now suggests that 1.4g of protein per KG of body weight is sufficient for growth – that works out to around 0.6g per lbs.
When people start ingesting large amounts of protein, the body can only use so much of it for muscle growth (it can absorb almost all the protein you throw at it) and the amino acids are used in gluconeogensis meaning it gets stored as sugar or fat.
Protein itself can cause the release of insulin from your pancreas. Insulin is the MOST anabolic hormone we know of and it increases protein synthesis which is great. However, insulin is also lipogenic meaning that it causes your body to store fats. Eating vast amounts of protein will mean you’ll have a lot of circulating insulin, which can lead to insulin resistance (so it’s less useful when you actually want it) and as, previously mentioned, can make you fat!
You don’t need THAT much protein to grow. 1.4g per KG per day will do it – for a 100kg man that’s only 140g.
I should also point out that when someone is dieting, more protein is required in order to prevent catabolism of muscle. This article is about muscle growth, for information on dieting, check out my site.
Written by Shiva, a med student with an interest in bodybuilding and powerlifting.