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Everything Endurance Athletes Need to Know About Protein Powder

Protein powders aren’t just for bodybuilders. Your simple guide to getting the most bang for your buck.

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Understandably, endurance athletes are often pre-occupied with meeting their nutrition needs to help keep up the pace. Certainly, this includes protein. To improve muscle recovery, boost strength, maintain healthy immune functioning, increase bone strength, and meet elevated caloric requirements, triathletes should not overlook the importance of dietary protein. While the Recommended Dietary Allowance (RDA) for protein for the general population is set at 0.8 grams of protein per kilogram of your body weight, research strongly suggests that training triathletes are better served by consuming 1.2 to 1.4 grams of protein per kilogram to meet increased needs including maintaining and building lean body mass. Active people stress their muscles, joints, and bones more, which accelerates protein breakdown. So, in turn, they require greater amounts of protein to build back what has been broken down.

While it’s certainly possible to get all the extra protein you need to support training from whole foods, many athletes turn to the various guises of protein powders as an ultra-convenient source and an insurance policy towards getting enough of the macronutrient. After all, what could be easier than whizzing some powder into a post-workout protein shake or even stirring some into morning oatmeal for a protein boost? And vegetarian or vegan athletes might feel like their diets are lacking in the macronutrient otherwise. This is why protein powder remains one of the top-selling supplements among the fitness crowd. Undeniably, a protein powder can deliver the necessary amino acids to your muscles in an efficient manner. 

Protein powders are essentially made by isolating the protein from food such as milk, hemp seeds, or yellow split peas and then dehydrating it into a powder. They’re typically mixed with water or other ingredients in blended smoothies, but the powders can also be stirred into items like oatmeal, yogurt, and pancake batter. The good news is that a new generation of protein powders on the market have improved what is available, with consumers now finding more options that are less heavily sweetened and gritty tasting.

But you’ve probably been left scratching your head while scouring to find the right protein powder for you. (Seriously, what is all of that stuff in those tubs and why are there so many options with so many promises?) We’re here to help. Here’s what you should know about your options and how to pick a winner.

RELATED – Ask Stacy: Which is Better, Whey or Plant Protein?

Don’t Give Protein Powder Too Much Credit

The stuff isn’t a muscle-building, performance-enhancing cure-all. Yes, protein powder can be a valuable part of your nutrition plan and fill in any gap, but it’s important to think of these as what they are, something to supplement an already well-balanced diet. You should be getting the majority of your protein from food sources. Protein-rich foods, including yogurt, eggs, legumes, meats, fish, and nuts, and then add other vital nutrients and antioxidants to your diet in addition to protein—a nutritional matrix no powder can match.

One study did find that runners who took a protein powder supplement (whey isolate and beef hydrolysate) daily for 10 weeks experienced a shift in their microbiome towards a higher concentration of less beneficial bacteria, suggesting it’s a good idea to not go powder crazy. But this outcome needs to be supported by a lot more research using different proteins in different quantities. Making sure to eat plenty of dietary fiber while using protein supplements could be a way to make sure your microbiome doesn’t suffer and is populated mostly by the good guys.

Whey Is Still the Gold Standard

One of the most important things to consider when it comes to protein powder is where the protein comes from. Whey protein is the most popular type of protein powder and, barring dietary restrictions, an excellent, well-researched choice. Typically, it is a byproduct of cheese and Greek yogurt that may otherwise be discarded. So by drinking whey protein, technically you’re recycling. The poster child of protein powders is widely available, fast-digesting, easily absorbed, and contains the highest amounts of the amino acid leucine. Of all the amino acids, it appears to be leucine that is the most important for encouraging muscle repair and growth in response to training. A study in the journal Nutrients found that frequent whey protein consumption did a better job than pea protein at mitigating the muscle-damaging effects of training which is likely a result of its higher leucine content. Whey has also been shown to outperform soy when it comes to building muscle. And it’s not just weightlifters who can benefit from a daily whey shot as research provides evidence that its daily usage may lessen the muscle damage brought on by running and even improve aerobic performance, perhaps via its ability to encourage increased muscle mass. 

A Case for Casein

Another milk-based protein type is casein. When enzymes are added to heated milk, they cause caseins to coagulate and separate into curds. These solids can be washed and dried to create casein protein powders. Casein digests significantly slower than whey protein, making it suitable to take before sleep or a period of intermittent fasting when there will be a prolonged amount of time between food intake to keep a steady flow of amino acids going to your muscles for improved training adaptations. The other benefit of casein is that it’s noticeably thicker than whey making it more likely to keep you feeling fuller for longer. But because of casein’s unhurried digestion and lower leucine content, whey protein is a better choice post-workout. 

Plants Work, Too

The emergence of plant-based protein powders is a boon to vegans and people with dairy sensitivities. And science demonstrates that options like soy or pea protein, which is derived from yellow split peas, can also help support training efforts including maintaining and building lean body mass. And manufacturers have been working hard to improve taste and solubility. Still, you’re likely better served by opting for brands that contain a mix of plant proteins or blending together different types since many are considered “incomplete,” meaning they lack one or more of the nine amino acids found in complete proteins like whey. In short, a blend can create a more enhanced amino acid profile. For instance, while pea protein is hypoallergenic and easily digestible as well as being rich in certain amino acids including glutamine, lysine, and arginine, it’s deficient in the essential amino acid methionine. But add rice protein to the mix, which is extracted from whole brown rice kernels, and you get the necessary methionine to better kickstart muscle repair. This concern can also be alleviated by making sure to eat a variety of other high-quality plant proteins like quinoa and tofu during the day.

Soy and hemp protein powder are notable exceptions as they both contain a full arsenal of essential amino acids, although both have lower levels of leucine than whey. Soy protein isolate offers more protein and leucine than just soy protein. 

Vegetable powders are also great to use for baking purposes and in pancakes, because they’re not as heat-sensitive as dairy proteins and produce items with better texture. But many don’t mix as effortlessly with liquid as does whey protein so require a blender to make a drink that goes down easy. 

Make sure you check the grams of protein per scoop. Some brands may be significantly lower in protein than other plant-based options, especially if they include add-ins like fiber and fruit powders. 

You Can Play the Field

Beyond whey and plants, there are a handful of other good-quality protein powders out there that can also get the job done. These include egg protein powder, paleo-friendly beef protein, and even cricket protein powder which you should know contains all the necessary amino acids to spur muscle recovery and growth. 

Know the Protein Powder Lingo

The protein listed in the ingredient list of your powder of choice may indicate it’s an isolate or concentrate. Protein isolate is the most finely filtered form of the powder, meaning it contains very little stuff other than protein such as fat, fiber, or lactose. This creates a product that is at least 90 percent protein by weight. Concentrate tends to be more budget-friendly and contains more calories from fat and carbs at the expense of protein–they typically top out at about 80 percent protein by weight, although can be lower than 50 percent which is not ideal. So the grams of protein per serving will be more in an isolate powder than a concentrate. But for most people’s needs, this is hardly a deal-breaker as a concentrate powder can still deliver adequate amounts of high-quality protein to support your muscle needs. 

Some products contain a mix of isolate and concentrate protein in what they call a “proprietary blend.” You need to be leery of this as the ingredient label may list this: Proprietary blend (whey concentrate, whey isolate). The concern here is that the consumer has no idea how much of each they are getting. It could very well be 90 percent less protein-dense concentrate and only 10 percent isolate, despite a price tag that is similar to what a 100 percent whey isolate would demand. Looking at the amount of protein relative to the serving size will give you an idea of what you are getting. More protein per gram of powder indicates a higher quality product. 

If lactose doesn’t sit well with your stomach then you should opt for whey protein isolate as it contains less than concentrate. You can also look for “isolated” soy protein which contains very little gas-producing oligosaccharides. 

You may also come across whey protein hydrolysate which is made using a process that breaks down the building blocks of proteins, called peptides, into something that is almost “pre-digested” making it theoretically easier to digest and absorb. But there is very little data to show that this pricey option results in noticeably greater gains than other types of whey. Plus, hydrolysate’s tend to have a more pronounced bitter flavor. 

Do the Math

Be it animal-based or plant-based, ideally you’re looking for a powder that delivers at least 20 grams of protein per serving or a ratio of about 150 calories per 20 to 25 grams of protein. Just keep in mind that scoop sizes vary and some products list their serving size as two scoops. So if you just blend up a single scoop you could be missing out on the necessary amount of protein. Despite what some companies will encourage, you most certainly don’t need more than 30 grams of protein in a serving, even after a hard workout. Add-ins like vegetable powders and fibers included in several plant-based protein powders can be helpful for overall nutritional needs but be aware that these can lower the amount of protein in a serving as they demand some space in each scoop. 

Avoid Protein Spiking

This is a term where some manufactures of whey protein powder will sneak in some non-protein nitrogen-containing substances into their blend that will be counted towards the total amount of protein. These can include creatine, a cheap free-form amino acid such as glutamine, or some sort of mystery amino acid matrix, all of which can be used to make up for a lack of protein quality in the first place. Brands that list the full amino acid profile on their label are more likely to be transparent with what they are making their product with. A good target for whey powders is a ratio of two parts leucine to one part isoleucine and valine–the two other branched-chain amino acids that also play an important role in muscle protein synthesis. 

Watch Out for the Sweet Stuff

If not opting for a plain flavored protein powder it’s likely to contain some sort of sweetener. Flavors like snickerdoodle, cookies and cream, caramel, and birthday cake are a tip-off there is going to be some added sweet stuff in the tub and perhaps bring the powder closer to candy than a useful supplement. Look for options with no more than 3 to 5 grams of added sugar in a scoop. Many companies also use artificial sweeteners like sucralose or low- to zero-calorie so-called “more natural” ones like stevia or monk fruit extract to keep carb calories lower. That’s a noble pursuit, but you’ll have to decide if you’re comfortable blending these into your post-workout drinks. One benefit of choosing unsweetened plain powder is that you can better control the desired flavors of your blender drinks. After all, a vanilla-flavored protein powder is always going to give you a vanilla-flavored drink. 

Listen to Your Gut

Make sure the protein powder sits well in your stomach. Whey and casein powders are made from milk, and while most of the lactose is removed during processing, they can still be hard to digest for some. Additionally, your stomach may cry foul when exposed to certain compounds in plant-based powders like oligosaccharides in soy protein or prebiotic fibers such as inulin. Sugar alcohols added for sweetness may cause gas and bloating in some people. So, if after a couple of smoothies you are still experiencing stomach woes including lengthy periods of uncomfy bloating consider trying a different brand of powder. 

Also, Listen to Your Taste Buds

With so many options on the market, don’t be afraid to judge by taste. Some powders are befallen by an overly chalky texture, have an unappetizing after taste, or are much too saccharine making them an uncomfortable experience for taste buds. Some sugar alternatives like stevia and monk fruit extract can alter flavor in a way that does not appease everyone. If you don’t like how a protein powder tastes consider moving on to another option (at least after you have finished that tub).

Look for Certifications

Since protein powders are considered a supplement they are not subjected to the same scrutiny by the FDA as is food. Meaning there is a chance you are getting more in each scoop than you want. According to a recent investigation by the Clean Label Project, an unsettling number of protein powders contain detectable amounts of contaminants such as pesticides, BPA, lead, and arsenic. Plant-based powders had higher heavy-metal levels than animal-based ones and being certified organic generally did not mean lower amounts. With that said, the detected levels may not necessarily be dangerous to your health when the powders are consumed in reasonable amounts, but it’s something to be aware of, especially if consuming multiple servings a day as contaminants may start building up in the body. (A good reason to once again stress the food first principle.) Just make note that this research conducted by a consumer advocacy group was not peer-reviewed and is just one lab analysis of the powders.

Worrisome to professional athletes who are subjected to drug testing is that a powder could be spiked with a banned substance that is not disclosed on the label. This is not common practice, but if it puts you at ease you can seek out brands that have gone through third-party testing. The NSF International (National Sanitation Foundation) “Certified for Sport” seal means a product contains what the label says it does, has been tested for contaminants and substances banned by major athletic organizations, and is made at a facility audited annually for quality and safety. Good Manufacturing Practices (GMP) is another certification that ensures the integrity of the food manufacturing process while the Informed Choice seal is another guarantee the powder contains no banned ingredients. Some brands will state on their website that each batch of their powder is tested to verify that contaminant levels are well below acceptable limits. 

10 of the Best Protein Powders

The best protein powders can help you recover better, build muscle, and pack more protein into your day. Here are some worth giving a whirl. 

Momentous Essential Grass-Fed Whey


Momentous Essential Grass-Fed Whey protein powder

Though a pricey option, this whey isolate powder is sourced from grass-fed cows and is free of any added sweeteners. The brand is also all about transparency including having an NSF Certified Sport seal of approval.

KOS Blueberry Muffin Organic Plant Protein


KOS Blueberry Muffin Organic Plant Protein powder

This pea-based protein has great berry flavor and is beefed up with potentially useful add-ins like prebiotic fiber, digestive enzymes, powdered veggies and spirulina. 

Nutiva Organic Plant Protein Superfood Smoothie


Available in vanilla and chocolate flavor, an organic protein blend of pea, hemp, sunflower and pumpkin seed makes this a complete protein package. The fruit and vegetable blend adds an antioxidant boost. 

Bob’s Red Mill Almond Protein Powder


Made from defatted ground almonds, each serving delivers 20 grams of protein and lends your smoothies a nutty essence. 

Optimum Nutrition Gold Standard Whey Double Chocolate


Each scoop of this the stalwart powder offers up 24 grams of high-quality whey protein primarily from isolate to show your muscles some love. Opt for unflavored if you want to avoid any artificial sweeteners and flavors. 

PB Fit Chocolate Plus


The addition of peanut flour to this plant-based powder makes it a strong candidate for deliciously boosting the protein in your oatmeal and pancakes. 

Paleopro Mayan Mocha


Perk up your shakes with this carb- and dairy-free powder made from grass-fed lean beef and egg – both of which have all the necessary essential amino acids.

GU Roctane Protein Recovery Drink Mix


The big mix of whey protein and quick-absorbing carbs are meant to spur recovery after you have emptied the tank. Research shows that a combination of carbs and protein after intense exercise can improve muscle glycogen replenishment to a greater degree than if you just took in a heap of carbohydrates on their own. 

hi! vanilla protein powder


Perfect for adventurous eaters, the cricket protein powder here is not only on par in terms of muscle-making quality as other animal-based powders but also ultra-environmentally friendly. The use of recyclable packets instead of plastic tubs ups the sustainability bragging rights. And, no, it doesn’t taste like eating bugs. 

Fit Formula Pro Vegan Creamy Vanilla


The Fit Formula Pro Vegan Creamy Vanilla protein powder

Featuring pea protein isolate and hemp protein, this powder contains one of the highest protein-to-calorie ratios of any plant-based option out there. Flaxseed powder adds a hit of heart-healthy omega-3 fat.