The protein and amino acid supplement market is big business. Bars, shakes, giant tubs of powder and specialist amino acid options dominate supplement shelves.
But the decision to use them is based more on slick marketing claims than anything else; protein supplements offer few real performance benefits that an athlete’s normal diet isn’t already delivering.
A good diet
Few athletes would disagree that more muscle is an advantage in their sport. And protein is the perfect source of the amino acid building blocks needed for new muscle growth and repair.
Taken together, strength training and sufficient protein will stimulate new muscle protein synthesis. The key word here is sufficient, because this is where protein supplement marketers like to extend to “the more the better”.
So, how much protein do sportspeople need? Consensus position statements such as those produced by the American College of Sports Medicine give the range of 1.2g to 1.7g of protein per kilogram of bodyweight.
But the top end of that range is for elite endurance athletes, power sportspeople and those in the early stages of a strength training phase. The “recreational athlete” should aim for the bottom end of the range.
So, how do those protein requirement numbers stack up against a regular diet? As an example, protein intake and bodyweights collected in the 2011-12 Australian Health Survey show the average Australian male already eats 1.2g and the average female 1.1g of protein per kilo of bodyweight.
And this is for mostly sedentary people who are not following any special “high-protein” training diet.
Sportspeople do have higher energy needs. But by simply eating a greater volume of food with a focus on higher protein content, it’s feasible for an athlete to get their protein requirements from food alone.
Numerous dietary surveys show the normal diet of strength-based athletes provides around 2g of protein per kilo of bodyweight per day. And that’s before using any protein powders.
Some merit
But protein supplements can’t be dismissed altogether. There are circumstances where supplementation is an appropriate and convenient option for athletes, such as when travelling or during an intense training schedule.
Athletes trying to drop weight on energy-restricted diets might find it harder to meet protein requirements, so a supplement could be used during that time. But those situations are the exception, not the norm for the bulk of supplement users.
Optimal muscle growth and recovery are more than just about meeting daily protein needs. And this is where the concept of protein timing around exercise has some credence.
Consuming protein after exercise is the best studied: about 20g of high-quality protein is sufficient to stimulate muscle protein synthesis after resistance exercise.
How long this window remains open is still debated, but it probably exists for several hours. So, fear not gymgoers, your muscle gains aren’t going to shrivel away because you didn’t chug down your protein shake five minutes after your last set of bench presses.
Combining all the protein timing research together leads to the conclusion that the body probably responds best to regular “doses” of protein throughout the day.
I like to call this new muscle growth optimisation protocol “regular meals and snacks with a focus on higher-protein foods”. Others may call it eating.
The right stuff
Not all protein sources are created equal. In the field of sports nutrition research, dairy protein consistently gets much of the attention, and for good reason.
The two main proteins in dairy are casein and whey. They are digested and absorbed at different rates, with whey appearing more quickly in the bloodstream. Most protein supplements are based on whey, but that’s more due to convenience because of its ready availability: it’s a waste product from cheese manufacturing.
Whey protein is of interest because it appears to have a stronger anabolic effect on muscle growth, thanks to a higher content of an essential amino acid called leucine.
It might not fill up glossy advertising in fitness magazines, but something as unsexy as chocolate milk is well supported by research as ticking all the boxes for an effective recovery drink.
Chocolate milk has a good mix of carbohydrates (to promote glycogen restoration and stimulate insulin release) and high-quality whey and casein protein.
It also has the added bonus of contributing to post-exercise rehydration.
But outside of cost, is there a downside to protein supplements? Yes, because they move the focus away from the undisputed benefits of a varied training diet.
Research is finding that body-conscious men are using these supplements for weight loss, setting them up for potential eating disorders.
The biggest performance gains in sport don’t come from protein supplements. They come from the triad of a varied diet, adequate rest and recovery, and the one supplement that all athletes need: BHW (bloody hard work).
l This article was first published on The Conversation (www.the-conversation.com). Crowe is an associate professor of nutrition at Deakin University in Australia.