Protein – are you eating the right types, the right amount, or even at the right frequency? Kevin Currell is Lead Performance Nutritionist for British Athletics and GB Short Track and gives us an overview of the body’s protein requirements and how to ensure muscle repair and resynthesis. Check out Kevin’s other articles about rehydration and foods that help provide maximum performance.
General nutrition requirements for the population as a whole are 0.8g of protein per kg of body weight. For an active person these recommendations may be a little low if the aim to maximise the repair and resynthesis of muscle. Rather than suggesting an overall amount let’s look at the dose, type and frequency of protein to maximise muscle repair and resynthesis.
Dose of Protein
Published in 2009 was a study from the laboratory of Prof Stuart Phillips, which nicely showed a dose response curve with post exercise intake of protein. There was an increasing response in protein synthesis post exercise up until about 20g of protein, thereafter there was no real increase in muscle protein synthesis. Follow up research has suggested there is a relation to body weight, with present guidelines showing 0.3 g per kg body weight of protein maximises the muscle protein synthesis response, and above this there are no real further increases seen.
Type of Protein
Food sources are preferable to supplemented forms if possible. The dose response curve seems to still hold true with meat especially. However, if there is a need to supplement with protein, which post exercise might be useful, whey protein is the clear winner.
Protein is made up of a series of amino acids. Some of these are known as ‘essential’ which means we must get them from our diet as our body cannot produce them. The appearance of these in the blood stream determines how quickly and effectively the machinery in the muscle which deals with protein synthesis is switched on. Whey protein provides these essential amino acids far quicker and effectively than other proteins, including soy or casein.
Frequency of Protein
Most of us have minimal protein intake in the daytime and only add big lumps of meat to our evening meal. However, this may not be the most effective way to stimulate the muscle to grow and repair. Research shows that 5-6 doses of protein spread across the day will lead to greater increases in protein synthesis. Try a slightly larger dose before bed of 0.4 g per kg body weight of a slow releasing protein such as casein, or maybe even Greek yogurt.
So how much protein should we eat per day? Well, if we want to maximise muscle synthesis and repair, 5 doses of 0.3 g per kg body weight of protein during the day and 1 of 0.4 g per kg body weight before bed will lead to a total of 1.9 g per kg body weight per day.