The protein powder supplement market is big business. Popular in the world of sport where muscle growth is a priority, the marketplace is dominated by glossy pictures of cut models and an ever-expanding list of claims for how these products will pack on the muscle. So, do the bros at the gym have it right in that you need these supplements if you’re serious about the gainz, or could plain old boring ‘food’ do the same job? In today’s podcast, I dig deeper into the world of protein and muscle growth and explore what the research says about protein supplements and then put this into context for what it means for the typical sportsperson.
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Episode transcript
To access the full episode transcript, go to the following link and select the individual podcast episode and then click on the ‘Transcript’ tab https://thinkingnutrition.buzzsprout.com
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The protein powder supplement market is big business. Popular in the world of sport where muscle growth is a priority, the marketplace is dominated by glossy pictures of cut models and an ever-expanding list of claims for how these products will pack on the muscle. So, do the bros at the gym have it right in that you need these supplements if you’re serious about the gainz, or could plain old boring ‘food’ do the same job? In today’s podcast, I dig deeper into the world of protein and muscle growth and explore what the research says about protein supplements and then put this into context for what it means for the typical sportsperson.
Links referred to in the podcast
Episode transcript
To access the full episode transcript, go to the following link and select the individual podcast episode and then click on the ‘Transcript’ tab https://thinkingnutrition.buzzsprout.com
Connect with me
Instagram: doctimcrowe
Facebook: Thinking Nutrition
Twitter: CroweTim
Hi, Tim here. Every now and then I take the opportunity to have a mini-break from putting out new episodes. But it also presents a great opportunity to dip into my back catalogue of episodes to pull out some that got a lot of listening engagement and which are also topics that I still get asked a lot about. And for this week, it is on one of the most common questions I’m asked about and that’s how much protein do we really need for muscle growth with exercise and do protein supplements do any good? As a postscript to this episode, its focus was mainly on muscle growth in more younger active exercises, but you may want to check out one of my recent podcasts, episode 66, on nutrition and healthy ageing and where protein recommendations go way up to help fight and prevent age-related muscle loss. Enjoy.
The protein powder supplement market is big business. Popular in the world of sport where muscle growth is a priority, the marketplace is dominated by glossy pictures of cut models and an ever-expanding list of claims for how these products will pack on the muscle. So, do the bros at the gym have it right in that you need these supplements if you’re serious about the gainz, or could plain old boring ‘food’ do the same job? In today’s podcast, I dig deeper into the world of protein and muscle growth and explore what the research says about protein supplements and then put this into context for what it means for the typical sportsperson.
The protein and amino acid supplement market is big business. Bars, shakes, giant tubs of powder and specialist amino acid supplements dominate supplement shelves. And all in the name of bigger and stronger muscles.
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. So, is there a role for additional protein through the use of supplements? Is it a case of more is better when it comes to protein and muscle gains?
To answer these questions, let’s first explore just how much protein sportspeople need. Consensus position statements such as those produced by the American College of Sports Medicine give the range of 1.2 grams to 1.7 grams of protein per kilogram of body weight. But the top end of that range of 1.7 g/kg bodyweight is for elite endurance athletes, athletes in strength and power sports and those in the early stages of a strength training phase as they ramp up their gym training. The “recreational athlete”, which describes the vast majority of active sportspeople, should aim for the bottom end of the range which is around 1.2 g/kg.
Just to add in the current science here, a 2017 meta-analysis of 49 studies looking at protein supplementation in resistance exercise training with a focus on muscle gains found that consuming protein above 1.6 g/kg BW didn’t result in any significant further muscle gains. I’ll link to the review in the show notes https://bjsm.bmj.com/content/52/6/376.long
All this talk of protein needs and expressing it in g/kg BW assumes you know how much protein you’re actually consuming in the first place. So outside of doing some detailed self-dietary analysis, let’s look at how those protein requirement numbers stack up against a regular diet. As an example, protein intake and body weights collected in the 2011-2012 Australian Health Survey showed the average Australian male already eats 1.2 g/kg BW and for the average female – it’s 1.1 grams of protein per kilogram body weight. And this is for mostly sedentary people who are not following any special “high protein” training diet.
Sportspeople do have higher energy needs so by simply eating a greater volume of food with a focus on a higher protein content, it’s very feasible for an athlete to get their protein requirements from food alone. No supplements needed.
And this concept that athletes can meet their protein needs with diet alone has been backed up by research with numerous dietary surveys showing the normal diet of strength-based athletes provides around two grams of protein per kilogram body weight per day. And that’s before using any protein powders.
But before you think there’s ‘nothing to see here’ when it comes to protein supplements, they 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 where it is physically difficult to access, prepare and consume food as proper meals. So ready-to-drink protein supplements and solid bars do make for convenient on-the-go snacks.
And then there is the case for athletes trying to drop weight on energy-restricted diets. They may find it harder to meet protein requirements so a protein supplement could be of use during that time. Under energy-restricted conditions, a greater proportion of amino acids are used for energy production, resulting in fewer amino acids available for muscle growth so the idea to supplement with protein has merit. While the research in this area is not as mature, there have been several commentary articles advocating that for athletes trying to drop weight and wanting to maintain and promote lean body mass, then protein intakes of between 2 and 3 g/kg BW could be considered. At these sorts of numbers, protein supplements enter the game.
Timing
So, moving on from daily protein requirements, what about the notion of optimising muscle growth through the timing of protein consumption? 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. Each time protein is consumed there is a small spike in muscle synthesis with a ‘dose’ of just 20-25g of high-quality protein is sufficient to stimulate muscle protein synthesis following resistance exercise. Having these protein ‘doses’ spread throughout the day can help to maximise exercise-induced muscular growth and aid repair of damaged tissue. Eating quantities of protein above this 20-25 g range in one sitting offers only a limited additional benefit with a very minor 10% further protein synthesis when the amount is doubled to 40 g.
However, despite the common recommendation to consume protein as soon as possible post-exercise, evidence-based support for this practice is currently lacking. That doesn’t mean that it shouldn’t be done, only that it shouldn’t be treated as Gospel despite what the bros at the gym may tell you.
How long the mythical ‘post-exercise muscle anabolism’ window remains open for is still debated, but it likely exists for several hours. So, fear not gym goers, your muscle gains aren’t going to shrivel away because you didn’t chug down your protein shake within five minutes of your last set of bench presses. There was a nice commentary paper on the topic of protein timing published in 2013 which I’ll link to in the show notes. https://jissn.biomedcentral.com/articles/10.1186/1550-2783-10-5
Combining all the protein timing research together leads to the conclusion that the body likely responds best to regular small ‘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 just call it eating.
Protein types
So that’s dose and timing done, what about the form of protein that is best to consume? Not all protein sources are created equal because of their amino acid makeup and how quickly they are digested and absorbed. In the field of sports nutrition research, it’s dairy protein that consistently receives much of the attention.
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 than casein. 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 after all.
Whey protein is of particular interest because it appears to have a stronger anabolic effect on muscle growth, thanks to a higher content of a specific essential amino acid called leucine. Leucine is a branched-chain amino acid and is particularly popular for its ability to build muscles and activate a protein known as mTOR, which triggers muscle protein synthesis.
The whey protein supplement market falls under three main types of protein.
First, there is whey protein concentrate which is typically 70-80% protein by weight with small amounts of lactose and fat. It’s one of the cheaper forms of whey.
Then next we have whey protein isolate or WPI. WPI powder is usually 90% protein by weight, with negligible amounts of carbohydrates and fat. Because of its higher protein content, it costs more than whey protein concentrate.
And finally, there is whey protein hydrolysate which is characterised by shorter peptides or amino acid chains, supposedly resulting in even more rapid digestion but evidence to date is conflicting.
With a growing interest in vegetarian diets, soy protein is also a popular option. Soy is considered a high biological value rapidly digested protein. It comes as both a soy concentrate and soy isolate. It is often used in mixed protein supplements and protein bars. While the balance of research indicates that whey protein may have a small edge for muscle building, some studies have found soy foods to be just as effective as whey protein in terms of its ability to promote gains in lean muscle mass.
One study, for example, found daily supplementation of 50 grams of soy, whey, or a soy-whey protein blend in 20 male athletes engaging in a weight-training program all resulted in similar increases in lean body mass and did not negatively affect testosterone or estrogen levels. I’ll link to the study in the show notes. This shows that soy protein can be just as effective as whey protein in building lean muscle mass as part of a dedicated exercise and nutrition regimen. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1997115/
Pea protein powder is another protein powder that is growing in popularity especially among vegetarians, vegans and people with allergies or sensitivities to dairy or eggs. Pea protein is not absorbed as fast as whey protein but is absorbed quicker than casein protein. There hasn’t been a lot of research into the muscle-building properties of pea protein, but at least one 12-week study involving 161 men doing resistance training who took either 50 grams of pea protein, whey protein or a placebo non-protein powder each day saw similar increases in muscle thickness between the pea and the whey protein and both were superior to placebo so there could be something to the pea protein story here. I’ll link to the study in the show notes https://jissn.biomedcentral.com/articles/10.1186/s12970-014-0064-5
Even studies that use lower-quality protein such as that derived from wheat can elicit a significant muscle protein synthesis response if greater amounts of it are consumed and this may be an effective strategy to compensate for its lower protein quality. So, the story here is that adequate protein overall in the diet may trump the source of protein so long as the diet is varied.
Vegetarian
On the topic of vegetarian diets, when it comes to strength and fitness, vegetarian athletes can perform just as well as their omnivore opponents.
To illustrate, in a recent study, the diets and physical attributes of 27 vegetarian and 43 omnivore competitive endurance athletes were looked at. Each person in the vegetarian group had followed the diet for at least two years and there was a mixture of vegan and lacto-ovo vegetarians amongst the group. There was little difference in protein intake according to body weight between vegetarians and omnivores. Although vegetarians ate more carbohydrates and fibre, they did have less vitamin B12 which is not so surprising. One interesting finding was that vegetarians had more iron in their diet than omnivores. But because plant-based iron is less bioavailable than animal-based iron (check out last week’s podcast which all about iron), then this may bring the vegetarians back on par with omnivores. And I’ll link to the study in the show notes. https://pubmed.ncbi.nlm.nih.gov/27854281
The key finding from the study though was in sports performance between the two groups. For the males, there was little difference in cardio-respiratory fitness or strength between the vegetarian and omnivores. The surprising finding though was in women. Women following a vegetarian diet had 13 percent greater VO2max scores than women eating an omnivore diet.
Downsides
So what about the downside of protein supplements? Outside of cost, there can be some negatives. For a start, they can move the focus away from the undisputed benefits of a varied training diet. Purified protein preparations contain few of the other nutrients needed to support the building of muscle, and the protein they supply is usually not needed by athletes who eat food as they’re likely already meeting their requirements. The supplements then just become excess protein which the body dismantles and uses for energy or stores it as body fat.
Excess protein does not harm the kidneys in healthy people, but it has been linked to worsening pre-existing damage so is something to be aware of if this could be you.
Summary
So, here’s what you need to know about protein. To maximise muscle growth with resistance exercise, daily protein recommendations sit at the upper end of about 1.6 g/kg BW. This target can be achieved by spacing protein-containing meals approximately 3–5 hours apart throughout the day. There can be some cases when protein supplements make it more convenient to hit this goal.
But the biggest performance gains in sport don’t come from protein supplements. They come from the triad of a broad varied diet, adequate rest and recovery, and the one supplement that all athletes need to be taking: it’s called BHW. Bloody hard work.
Research Wrap Up
Now on to my research wrap up segment where I profile a study that has grabbed my attention during the week and for this week, the topic is mental health. Interest in the link between nutrition and mental health is rapidly growing. Now a new study in young adults with depression finds that a switch to healthier eating can significantly reduce symptoms of depression.
A healthy diet is a common factor linked to a positive mental outlook. The problem with most of the observational research in this field though is that it is hard to tease out which one comes first. Are people in the depths of depression more likely to eat poorly because of their mood? Or does a poor diet worsen depressive symptoms?
There is now a small, but growing field of research, directly intervening with diet changes in people with depression to see how this can improve their outlook. One such study has looked at the link between diet and depression in young adults.
Adolescence and young adulthood are periods where there is an increased risk of depression. These are also critical periods for establishing healthy eating habits which will carry over into adulthood. So how nutrition influences the mental health of younger adults was the topic of a recent intervention study. And I’ll link to the research in the show notes. https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0222768
The study involved 101 adults aged between 17 to 35 years all who had moderate-to-high symptoms of depression. They all were considered to have a poor diet when assessed against Government healthy eating guidelines. Any person taking anti-depressant medication or receiving psychological therapy were required to stay on that treatment plan during the study.
The participants were randomly allocated into either a diet change group or a control group which meant following their regular diet. The diet change group were given advice on improving their diet, a healthy food hamper and a small amount of money for buying groceries to help with purchasing healthier foods. The diet changes focussed on having more fruits, vegetables, wholegrains, nuts, fish, legumes, eggs, tofu and lean meats according to the person’s individual dietary preferences.
The control group received no advice on diet and were left to continue their normal habits for the 3 weeks the study ran. Symptoms of depression and anxiety along with overall mood and performance on learning and reasoning tasks were measured at the beginning and end of the 3 weeks.
Those in the diet change group were indeed successful in making positive changes to their diet. With these diet changes, significant improvements in mood, depression and anxiety were all seen. No such changes were seen in the control group.
Three months after the study finished, follow-up was made with 33 of the participants to see how they were tracking. One in five of those in the diet change group were still keeping up with the healthy eating habits and for these people, their mood improvements stuck.
The clear downside to this study was that the control group did not get any general eating advice, financial support to buy food or check-in contact with the research team. Each of these factors potentially could have had an impact on mental health independent of diet changes. The results though are in line with a previous intervention study that did mostly control for these types of factors and equally saw a marked improved in depression symptoms with positive diet changes.
This study adds more support for the benefits of positive dietary changes in improving mental health. Counselling, emotional support, and medications all have their role to play and now it seems that diet is another cornerstone to consider in dealing with depression.
So that’s it for today’s show. You can find the show notes either in the app you’re listening to this podcast on if it supports it, or else head over to my webpage www.thinkingnutrition.com.au and click on the podcast section to find this episode to read the show notes.
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I’m Tim Crowe and you’ve been listening to Thinking Nutrition.