Ask an expert: how protein supports your sport goals

Maybe you’re thinking about building your muscle mass, or getting back to training even quicker after your last workout. Maybe you’re wondering how to beat your personal best again and again. Whatever your reason for wanting to boost your protein levels, our H&B nutritionist is here to share her protein and performance insights from working with professional athletes.

“Protein is a molecule made up of amino acids and is the basis of our body’s cell structure – from our hair and muscle to our organs,” says Emily. “Without adequate protein, we wouldn’t be able to function, so you could say it’s pretty important.”¹

Emily says that for an average, relatively inactive person, “daily recommended allowances¹ sit around the 0.75g of protein per kilo of bodyweight, so for a 60kg person that would be about 45g of protein,” says Emily. “That said, we’re starting to see³ that this might not be enough and we could be looking at double that in order to build muscle mass,” she explains.

Emily says that the timing of protein intake is just as important as the daily amount when it comes to building muscle and repairing it. “Protein, specifically whey protein, is most effective after a workout as opposed to before or during,” she says. “The reason for that is because it contains an essential amino acid called leucine, which can be used to stimulate muscle growth and repair.”⁵

“We used to think that to get the most from your protein source you had to have it within a protein window of around 30 minutes after exercise, but we now know that window is much longer – research suggests⁶ that it might actually extend for a few hours,” explains Emily. So as long as you're getting some sort of protein intake in that broad post-exercise window, it's just as beneficial as having it immediately after.

Protein can support weight loss in a few different ways according to Emily. “Firstly, it can help you feel fuller for longer (also known as ‘satiety’),” she says. “Compared to the other macronutrients – fat and carbohydrate – protein is going to keep you feeling much fuller. This could help to cut cravings throughout the day.” Research shows⁷ that opting for a high-protein breakfast can curb hunger later in the day.

There is research¹⁰ to say that protein alongside carbohydrate intake could actually be beneficial before and during a prolonged exercise, such as a long-distance run or bike ride. “Having them together can help to prevent that muscle protein breakdown, which will result in less damage to the muscles and potentially improve recovery as well,” Emily says.

When it comes to endurance exercise, yes. “Protein intake could actually be useful for recovery before and during exercise,” says Emily. “If, for example, you are exercising multiple times in the day then having that protein intake before or during your session can slow down the muscle breakdown process. This can also make your recovery period a little shorter,” Emily tells us. This is particularly useful for elite athletes or if you’re training for an event, as it means you’ll have a better chance of recovery between sessions.

Whey protein is one of the major proteins from milk – the other one being casein protein. Emily explains: “Around 20% of the protein in milk is whey¹¹ with the remainder being casein. In order to access that whey, the milk is heated and enzymes and acid are added which causes the casein in the milk to coagulate (it goes from a liquid to a solid), and then that liquid substance that's left is the whey protein. This is then washed and dried to produce whey protein powder.” You can find out more in our ultimate guide to whey protein.

Whey protein, compared to casein¹² (another type of protein), is more quickly digested and absorbed¹³ into the body. This means you can benefit from it fast. “It's also a different amino acid composition to casein making it more suitable to have after exercise,” says Emily. “Whey contains the amino acids called leucine, which triggers muscle protein synthesis – or in short, muscle rebuilding,” says Emily.

When we exercise, we cause stress and damage to our muscles, which is known as muscle protein breakdown – which is actually a good thing. “To recover we have to try and rebuild and repair those muscles and this is where muscle protein synthesis and leucine do the heavy lifting. Whey is more effective at doing that quick muscle repair and growth as it’s rapidly digested and absorbed,” she adds.

“If you're lactose intolerant and still want a whey protein then your two options are hydrolysis or isolate, as they’re virtually free of all lactose. And if you want a natural protein powder that’s free from lactose, then dairy-free ones such as hemp protein, soy protein, rice protein or pea protein are all good options,” Emily advises. You will often find that they contain no flavourings so they are great to add to soups, smoothies or porridge.

There are lots of reasons why protein deserves a place in your workout routine, especially fast-acting whey.