How important is protein intake in all of this?
The principals on how we gain muscle mass are that we have two main stimuli for our muscles to grow. One of those is physical activity (muscle contraction), and the other is protein intake. If you eat a meal containing protein and you haven’t done any exercise, that will in itself maintain a bit of muscle building. It will also suppress the breakdown of muscle a bit too. If you do a bout of exercise without taking any protein, that also stimulates muscle growth, but it actually helps stimulate some muscle breakdown too. So when we combine the two we get the best of both worlds and we get this synergistic response. You get the biggest effects on muscle growth and you also get a suppression of the breakdown of muscle. What you actually find is that, if you’ve done a bout of exercise before you eat a meal containing protein, your response to the protein in that meal is greater. So in other words, by doing some exercise you’ve sensitised your muscle, so that when you have some protein later in the day, more of that meal is directed to muscle growth. A way to think about it is – ‘you are what you eat’. So, for example, if you were to have a protein-based recovery drink after exercise, such as SiS REGO or Whey Protein, which contains ~22g of protein, over the next 4-5 hours, about 2g of that protein will end up as new muscle. So you are what you eat for that next five hours or so. But if you exercise before that, you become more of what you just ate.
So once consumed, what is the protein actually doing to help?
It’s the protein in a meal which stimulates this response from our muscles. Proteins are made up of things called amino acids – and you can think of these as the building blocks of the protein. We get various types of amino acids. Some of them our body can actually produce itself and some of them it can’t. For the ones it can’t produce we need to get them from our diet. They are known as essential amino acids. To stimulate the best muscle building response you need a good compliment of all of these. We know there are a few ones that are key for initially stimulating the muscle response. You can think of these protein components as signalling molecules, so when we eat a meal, the amino acids appear in our bloodstream and the muscle sees them, that signals our muscle to switch on muscle growth. But it can’t sustain that response unless it’s got other amino acids to act as the building blocks for that. An analogy to help with this is: you’ve got a builder building a wall – amino acids are telling that builder to put bricks on the wall. But he needs more bricks to actually continue that process to a meaningful extent. So they serve two purposes. When we exercise we need less of those signals to get the same response.
Is it true that we should be spreading out our protein intake across the day?
In terms of the amount of protein that maximally stimulates this muscle-building response, in a single meal it’s typically about 20-25g of protein. But that’s specific to animal-based protein, so milk, eggs or meats for example. That’s the dose that we know stimulates that response. That’s not to say that plant-based proteins can’t achieve that response. It just means that you need a higher dose to achieve the same response. If you’re vegetarian one of the things you should do is try to mix your sources of protein, to try to ensure you’re getting the full complement of the amino acids. The other thing you should do is try to aim for a higher total protein intake, compared to if you were someone who ate meat, milk or so on. The other thing related to that is, because we can only stimulate that maximal response with ~20g over a four-hour period – eating more protein than that won’t result in a greater response. In order to get the most benefit from muscle building over a day, it’s best to spread the protein intake out. What we sometimes find is that, certainly in most western countries, people might have a relatively low-protein breakfast – for example toast and tea or orange juice. That means they’ve initially missed out on this opportunity to stimulate a bit of muscle building. Then in their evening meal they might have a big steak, which could be 50g of protein and a lot of that is essentially wasted – it’s not being used for muscle growth. Whereas for the same total protein dose across a day, if you spread it out so you’re getting a little more at breakfast, and perhaps a little bit less at dinner, you can get more muscle growth from the same total protein intake.
We’re always advising our riders on meal plans, but they are really good in the sense that they understand the importance of protein, especially in recovery from exercise. We’ve provided them with a lot of Science in Sport products, so for instance taking the Whey Protein after exercise helps them achieve that goal.