Take your gains to a whole new level.
Knowing the ins and outs of protein powders can help you take your gains to a whole new level. Here’s everything you need to know about how to make that happen.
We’ve long recommended that you consume the majority of your daily protein intake from lean whole-food sources, such as beef, poultry, seafood, pork, eggs and dairy. But there are certain times of the day when protein powder provides clear benefits over whole food.
Not that long ago, few options were available as far as types of protein powders to choose from. The limited choices mainly included milk-based protein powders, such as whey protein or egg white protein, long considered the gold standards of protein powders. And although these two forms are still top notch, there is now a plethora of other options that have benefits that whey or egg protein can’t provide.
So which are the best for you and your specific goals? It’s all here — the protein powders available to you, the technology that manufacturers are using to create them, and the best way to optimize the results you experience with them.
1. MILK PROTEIN
Milk has been a popular “food” for athletes and others interested in building muscle size and strength for centuries. Milk is a rich source of two of the most beneficial proteins you can get — whey and casein.
A cup of whole milk provides 8 grams of protein, 8 g of fat and 11 g of carbs (lactose or milk sugar). The remainder is mostly water. The protein is about 80% casein and 20% whey. Since casein makes up the majority of this protein, it mainly provides benefits similar to casein along with some of the benefits of whey.
Within milk protein are specific protein fractions that provide numerous health, performance and physique benefits. These include: beta-lactoglobulin, alpha-lactalbumin, glycomacropeptide and immunoglobulins — fractions of whey that strengthen the immune system. Protein manufacturers have figured out that by removing the water, fat and carbs from milk, the result is not only a concentrated protein source that is then dried and powdered, but also a more effective way of extracting the multitude of benefits of milk proteins, without imparting all the added calories from the carbs and fat.
MILK PROTEIN CONCENTRATE
Filtration of whole milk removes much of the carbs and fat. It is often concentrated by a process known as ultrafiltration, creating a protein content of about 80%.
MILK PROTEIN ISOLATE
Further processing of the concentrate yields milk protein isolate, which provides greater than 85% protein. Most of the fat and carbs are eliminated, but both the casein and whey proteins are largely unaffected.
MILK PROTEIN QUICK FACTS
WHAT: The protein derived from cow’s milk after removing the water and the majority of the carbs and fat.
WHY: Milk proteins provide a large amount of casein (80%) and some whey (20%), so they offer benefits of both casein and whey.
WHEN: After workouts, between meals and before bed.
KINDS: Milk protein concentrate, milk protein isolate.
2. WHEY PROTEIN
Whey protein is the soluble portion of milk protein. Whether you know any of this or not, it’s likely that you’re familiar with whey and the fact that it’s one of the most popular protein powders on the market. Whey is so popular today because, as scientists have discovered, it is a superior protein when it comes to stimulating protein synthesis — the cellular process by which muscles increase their size.
In addition to protein synthesis, whey has many other benefits. The most important is the ability to enhance blood flow to muscles. Whey contains peptides (short protein fragments) that inhibit an enzyme known as angiotensin-converting enzyme, which normally increases the constriction of blood vessels. By inhibiting ACE, these peptides allow greater blood vessel dilation, enabling more blood flow to exercising muscles, which enhances the delivery of nutrients (such as the amino acids in whey), anabolic hormones (such as growth hormone and testosterone) and oxygen to muscle during exercise — all critical for energy and strength during a workout and for recovery and growth afterward. The increased blood flow also enhances the muscle pump you get. This aids in lowering blood pressure, as research has confirmed. Whey also boosts levels of the powerful antioxidant glutathione in the body, lowers total and LDL (bad) cholesterol and may even help to reduce the risk of certain cancers.
WHEY PROTEIN CONCENTRATE
A high-quality, complete protein that contains some carbohydrates and fats. Most protein counts fall within the 70%-80% range, depending on the amount of filtering performed. The filtration process involved to create whey protein concentrate is typically microfiltration or ultrafiltration. Due to the limited processing that it goes through, it is typically the cheaper of the whey proteins. Minimal processing also leaves most of the beneficial whey peptide fractions in place. It’s a good choice for those who are concerned about getting the health benefits of whey or those on a budget.
WHEY PROTEIN ISOLATE
A purer form than concentrate due to additional processing involving either longer filtration times or additional steps in the manufacturing process, such as microfiltration or cross-flow microfiltration. Another process that some manufacturers use to produce whey protein isolate is ion-exchange chromatography. Regardless of the methods employed, increased processing enables the production of a whey protein with a concentration higher than 95% protein.
WHEY PROTEIN HYDROLYSATE
This form is produced when whey is taken through the process of hydrolysis. This process involves breaking the longer protein chains down into smaller peptide fragments, meaning that this protein is digested and absorbed even faster than whey protein isolate.
MICRONPARTICULATED WHEY PROTEIN
A new whey protein technology that involves the micronparticulation of whey protein isolate. This is a highly specific micronization of the whey protein, which reduces protein particle size by one-fifth and, therefore, increases the ratio of surface area to volume. Greater surface area improves the solubility of the protein in fluids, which helps with its ability to mix into a protein shake and increases the speed of digestion. The larger surface area also allows enzymes in the digestive tract to digest the protein quicker, making this a very fast-digesting protein that is even faster than standard whey protein isolate.
WHEY PROTEIN QUICK FACTS
WHAT: The soluble portion of milk protein.
WHY: Whey protein digests very rapidly, which means that it delivers its amino acids to muscles very rapidly and therefore boosts muscle growth.
WHEN: First thing in the morning, before and after workouts and between meals.
KINDS: Whey protein concentrate, whey protein isolate, whey protein hydrolysate, micronparticulated whey protein.
HOW WHEY STIMULATES PROTEIN SYNTHESIS
- Whey is one of the fastest-digesting protein powders you can buy, meaning its amino acids get rapidly absorbed into your bloodstream and travel to the muscles.
- Whey has one of the highest leucine contents of all protein powders. Research shows that leucine directly stimulates protein synthesis.
- Whey boosts insulin levels. The anabolic hormone insulin is also important for stimulating protein synthesis.
3. CASEIN PROTEIN
Whey makes up only about 20% of the protein in milk; casein makes up the remaining 80%. Unlike whey, which is soluble and, therefore, rapidly digested and absorbed, casein takes the form of tiny micelles, or globules. These are insoluble in liquid and actually clot up in the stomach. In doing so, they take much longer to digest and absorb, with some forms of casein protein taking up to 7 hours to be fully digested and absorbed.
Past research has shown that casein’s slow digestion rate enables it to enhance muscle growth by stopping muscle protein catabolism (breakdown). In addition, casein may be almost as effective at stimulating muscle protein synthesis as whey, at least after workouts, as research from The University of Texas Medical Branch (Galveston) has more recently suggested. In fact, one study reported that trained lifters adding casein to their post-workout shake for eight weeks gained more muscle mass than those using just whey.
Although casein has become popular due to its slow digestion, that is not the only trick it has in its jug. Of all the protein powders, casein happens to have one of the highest concentrations of the amino acid glutamine, which provides a multitude of functions that aid bodybuilders. Glutamine actually helps to increase levels of the branched-chain amino acid leucine in muscle fibers, which enhances protein synthesis and, therefore, muscle growth. Because the immune system requires glutamine to function, getting in more of it prevents the immune system from stealing it from muscle fibers and, therefore, helps to further prevent catabolism. Glutamine also helps to boost growth hormone levels and it can even aid fat loss by increasing the amount of calories and fat burned at rest and during exercise.
Manufactured by separating the casein protein in milk from the lactose and fat, as well as the whey protein, by the processes of ultrafiltration and then microfiltration. Even after processing, micellar casein can still form micelles upon rehydration with fluid. Although clumping makes it less easy to mix in liquid, it does make it the slowest digesting of the casein proteins. Micellar casein is a good choice for before bed and also post-workout to boost the benefits of whey.
CASEINATE (CALCIUM CASEINATE, POTASSIUM CASEINATE, SODIUM CASEINATE)
Caseinate protein powders are made by adding calcium, sodium or potassium. Caseinates typically contain greater than 90% protein and are the most soluble form of this protein, meaning they mix much easier in fluids. However, the fact that caseinates are more soluble in fluids means they clump less in the stomach, digesting a bit faster than micellar casein, yet still much slower than whey protein.
CASEIN PROTEIN HYDROLYSATE
Like whey protein hydrolysate, this protein is manufactured by hydrolyzing the casein protein to form shorter protein chains. Because they are shorter, these proteins require less digestion in the stomach and, therefore, are digested more rapidly, unlike the other casein proteins. This property makes it a good choice to use when you need a faster protein, such as before and after workouts and first thing in the morning.
CASEIN PROTEIN QUICK FACTS
WHAT: The globular portion of milk protein, making up the majority of the protein in milk.
WHY: The casein globules reduce the speed at which casein is digested, making it a very slow-digesting protein.
WHEN: After workouts (with whey), between meals and before bed.
KINDS: Micellar casein, caseinate (calcium caseinate, potassium caseinate, sodium caseinate), casein protein hydrolysate.
4. BEEF PROTEIN
Although you might think that beef protein is equivalent to throwing a hunk of steak into a blender and drinking it, it is far more involved than that. In a nutshell, beef protein powders are steak with everything — mainly fat and cholesterol — removed except for the amino acids that make up the muscle protein, including the creatine that muscles store. It is also a rich source of vitamins A and D and the B vitamins. Beef protein makes a very good alternative choice of protein for those who must avoid lactose due to allergy or intolerance issues.
BEEF PROTEIN ISOLATE (HYDROLYZED)
Beef protein isolate starts with USDA grade beef — in essence, steak — that is ground up. The ground beef is then heated to hydrolyze the protein. The result is similar to when whey protein or casein protein are hydrolyzed — the protein is essentially “predigested” into smaller protein fragments which reduces the time it takes to digest in the stomach. After the heating hydrolysis, the beef is filtered to remove the fat and cholesterol. Next it undergoes evaporation to remove the water and concentrate the protein to about 99%. Finally, it undergoes spray drying to create a beef protein isolate powder. Because this protein is an isolate and is hydrolyzed, it is rapidly digested and, therefore, is a good protein to take before and after workouts, as well as first thing in the morning and between meals.
BEEF PROTEIN QUICK FACTS
WHAT: The protein derived from beef after removing the fat and cholesterol.
WHY: It is a fast-digesting protein (like whey) that is a good source not only of essential amino acids, but also creatine.
WHEN: First thing in the morning, before and after workouts and between meals.
KINDS: Beef protein isolate.
5. EGG WHITE PROTEIN
Egg white, also know as egg albumen, is one of the highest quality proteins available. Some call it the perfect protein due to its amino acid makeup and the body’s ability to utilize it properly.
Egg white protein is particularly high in BCAAs, which can help drive protein synthesis. In fact, research shows that egg white protein has similar effects on stimulating protein synthesis as milk protein. It is also rich in the amino acid arginine, which stimulates nitric oxide production. NO dilates blood vessels, resulting in increased blood flow to muscles, which helps to deliver more oxygen, nutrients and anabolic hormones for better energy and a bigger pump during workouts and better muscle recovery and greater muscle growth afterward. In addition, arginine works to boost GH levels, which is critical during and after workouts. Egg white protein is also a high-sulfur-containing protein, which is critical to the body’s hormone-producing pathways, meaning it can further enhance muscle growth.
Egg white contains as many as 40 different proteins. Although most of them have not been determined, there are a few that make up the majority of the protein in egg white and have been extensively studied. Of these proteins, ovalbumin, a type of glycoprotein (protein that has carbohydrates attached to it), comprises the majority, making up about 55% of the protein in egg white. You will sometimes see egg white protein listed as ovalbumin.
Egg white protein is moderately fast-digesting. It falls between fast-digesting whey and very slow-digesting casein. With its rate of digestion, egg white is able to not only boost protein synthesis, but also to prevent muscle protein breakdown, as shown in clinical trials. Egg white protein is virtually devoid of carbs and fat, making it a good choice for those who are dieting. Egg white protein powder is an alternative for those who are very lactose intolerant or allergic to milk proteins and don’t handle well the milk derived proteins whey and casein. It is a great way for those who don’t like the taste of cooked eggs, the hassle of storing fresh eggs or the mess of cracking eggs, to still get the benefits of egg protein. On labels, typically, egg white protein powder is called just that — egg white protein.
EGG WHITE PROTEIN
This is basically dehydrated egg whites that have been processed into a fine powder. Some manufacturers use spray drying to produce a finer egg white protein powder. It also goes through a pasteurization process to prevent salmonella and inactivate the avidin protein.
EGG WHITE PROTEIN QUICK FACTS
WHAT: The protein derived from chicken egg whites.
WHY: Rich source of the BCAAs and arginine.
WHEN: After workouts (with whey), between meals and before bed (with casein).
KINDS: Egg white protein (often called ovalbumin).
6. SOY PROTEIN
Soy protein is the powerhouse of the plant proteins, although it is a bit misunderstood and wrongly classified as a poor protein choice for men. The biggest misconception about soy is that, because it contains phytoestrogens (plant chemicals that have estrogenlike properties), it lowers testosterone and raises estrogen levels. Yet study after study has shown that this is not the case. A recent meta-analysis (an examination of previous research) analyzed the 15 quality studies done on soy and testosterone levels. The researchers concluded that soy does not alter testosterone concentrations in men.
Another misconception about soy is that it does not increase muscle growth as well as milk-based proteins. Yet one study found that when male bodybuilders supplemented twice daily with either soy protein concentrate powder, soy protein isolate powder, soy/whey protein powder blend or whey protein isolate powder during a 12-week weight-training program, all increased muscle mass similarly regardless of what protein they were taking. This supported a Canadian research project that reported similar results in untrained subjects.
Soy seems to stack up similarly to whey, and it also has benefits that whey and other protein powders do not. The first is soy’s ability to raise GH levels, which is likely due to its high arginine and lysine content. It also boosts NO levels. Virginia Polytechnic Institute and State University (Blacksburg) researchers found that the soy phytoestrogen genistein increased NO levels by raising the amount of nitric oxide synthase (the enzyme that catalyzes the conversion of arginine into NO). In addition, soy better enhances muscle recovery. An Ohio State study on muscle growth comparing soy and whey protein bars reported that men taking soy had better antioxidant protection following exercise. Another study, published in the International Journal of Sports Nutrition and Exercise Metabolism, found that when trained men consumed 40 g of soy protein before lifting weights for four weeks, they had better antioxidant protection following the workout as compared to men who consumed whey protein. And the Journal of Sports Medicine and Physical Fitness reported that women consuming soy protein for four weeks had less oxidative muscle damage following exercise than those consuming whey (who had no such reduction).
If all those benefits weren’t enough, soy can also enhance fat loss. A review in an issue of the journal Obesity Reviews concluded that soy protein can aid fat loss, possibly by decreasing appetite and calorie intake. In fact, a study by researchers in the departments of Obstetrics/Gynecology and Pharmacology at the University of Alabama (Birmingham) reported that women receiving a daily soy shake containing 20 g of soy protein plus 160 milligrams of isoflavones lost abdominal fat, while those consuming a 20-g casein shake gained fat around their waist and abdomen. Because soy may increase NO and GH levels, as well as enhance muscle recovery, it’s a great protein to add to your pre- and post-workout protein shakes.
SOY PROTEIN CONCENTRATE
This form of soy is usually about 65% protein, with the rest being carbs and fat. It is manufactured by placing soybean flakes or flour through either a water or alcohol extraction process to remove some of the carbs. Then it undergoes a drying and grounding process to produce soy protein concentrate powder. It can cause gas in some people due to the indigestible carbs it often contains.
SOY PROTEIN ISOLATE
This form of soy is made from soy concentrate that is further processed to remove most of the fat, carbs and gas-producing factors for a product that is more than 90% protein. This type tends to be digested a bit slower than whey, but faster than casein.
SOY PROTEIN QUICK FACTS
WHAT: The protein derived from soybeans after removing the majority of the carbs and fat.
WHY: Soy protein may boost GH and NO, and enhance muscle recovery and fat loss.
WHEN: Before and after workouts (with whey).
KINDS: Soy protein concentrate, soy protein isolate.
Soy isn’t the only plant protein available. Plant proteins offer great alternatives to milk-based, beef or egg proteins. Whether you avoid animal-based proteins for ethical reasons or due to allergies or intolerances, many plant-based protein powders offer benefits that the animal-based protein powders do not. Consider adding some of these to the mix.
- Brown rice protein, which ends up being about 70% protein, has about four times the amount of arginine as whey, and more arginine than any other protein powder we’re aware of. Since arginine is readily converted to NO in the body, using brown rice protein can help to enhance blood flow to your muscles for better delivery of nutrients to the muscle, a bigger pump during your workouts and even better recovery after workouts. Brown rice protein is also rich in the amino acid glutamine.
- Pea protein powder is about 85%-90% protein. Although peas are low in the essential amino acid methionine, pea protein powder has an amount of methionine similar to soy, which has been shown to be effective for producing muscle mass gains. Yet pea protein powder is fairly rich in glutamine and BCAAs. In addition, it has almost three times the arginine content of whey protein.
- The major protein in buckwheat protein powder is albumin, which is similar to the major protein found in egg whites. In general, buckwheat protein contains a high concentration of essential and sulfur containing amino acids for supporting muscle mass and recovery. Another benefit of buckwheat protein is its ability to help lower cholesterol.
- The end product in cranberry seed protein powder is about 35%-40% protein. Although this is extremely low as protein powders go, the remaining 60%-65% of the powder is fiber (both soluble and insoluble), as well as the healthy omega-3 fats, omega-6 fats and omega-9 fats. The protein is also reportedly rich in BCAAs and, of course, antioxidants. The major problem with cranberry protein powder is that it is not readily available.
- Hemp seed protein powder is made up of two major proteins: 1) edestin, comprising about 65% of the protein, and 2) albumin, which makes up the remaining 35% of the protein. Most hemp protein powders rarely supply more than about 50% protein. However, the protein in hemp protein powder is fairly rich in arginine and BCAAs. Hemp protein powder is also a good source of essential fatty acids and fiber.
- Brazil nut protein powder is rich in all the essential amino acids, it also supplies monounsaturated fats, important for general health, especially cardiovascular health.
THE PROCESSES OF PROTEIN POWDER PRODUCTION
There are numerous processes that protein manufacturers use to create a protein powder from a whole food source, such as milk, beef, eggs or plants.
- ULTRAFILTRATION is the preferred method employed to extract milk proteins used in the manufacture of milk protein concentrate. This concentration process uses varying degrees of pressure to force the liquid matter through a porous membrane with holes that are only nanometers in diameter. The large proteins cannot pass through the tiny holes and are trapped on the membrane and then collected. These concentrated milk proteins undergo evaporation and then spray drying, which results in a powder.
- MICROFILTRATION separates the protein from the carbs and fat through a natural, nonchemical process that uses filters to separate the protein based on size, while still maintaining the majority of the beneficial fractions.
- CROSS-FLOW MICROFILTRATION is similar to microfiltration and ultrafiltration, but takes a bit longer, allowing even better separation of the protein to provide a purer protein (higher protein concentration) and still maintain the subfractions. The CFM processing method uses a low temperature, microfiltration technique that allows for the production of very high protein contents (>90%), the retention of important subfractions, extremely low fat and lactose contents, with virtually no undenatured proteins. CFM is a natural, nonchemical process that employs high-tech ceramic filters, unlike ion exchange, which involves the use of chemical reagents, such as hydrochloric acid and sodium hydroxide. CFM whey isolate contains high amounts of calcium and low amounts of sodium.
- METAFILTRATION removes any impurities from the protein to create a purer protein powder.
- ION-EXCHANGE CHROMATOGRAPHY uses chemicals such as hydrochloric acid and sodium hydroxide to separate the protein. This process is often used with whey protein to produce the highest protein content of all whey proteins. The drawback is the fact that some of the beneficial subfractions may be lost.
- HYDROLYSIS involves the separation of the protein into peptides (smaller protein fragments only a few amino acids long). Hydrolysis uses heat and/or enzymes to break some of the amino acid bonds in the protein chain to create shorter proteins and allows the protein to be digested and absorbed more rapidly in the body. This process is used to make whey protein hydrolysate, casein protein hydrolysate and some beef protein isolates.
- INSTANTIZING is a process in which the spray-dried powder is first wetted and then redried. The degree of rewetting is closely controlled to permit the particles to stick together and form aggregates before redrying. In these products, the small particles are fused together, but the points of contact are so few that practically all of the surfaces are available for wetting. The aggregates, however, are sufficiently stable to prevent lumping when stirred into water or other fluid. This creates protein powders that easily mix into fluid without the need of a blender.
- MICROENCAPSULATION This is a very advanced technology, which provides a sustained-release action. This is typically done by mixing the protein with heated oil, such as soy oil, which coats the protein particles and gives them a slower digestion rate.
Although protein powders offer numerous benefits, to truly maximize their effectiveness you need to have a plan. There are several ways to ensure that you are maximizing the benefits they offer. The two main ways to do so involve 1) the timing of when you drink protein shakes and 2) the combining of different types of protein powders.
There are four critical time windows when protein powders trump whole foods. Specific protein powders outweigh whole foods mainly in digestion time and in their very high concentrations of particular components in the protein powders.
CRITICAL WINDOW 1: First thing in the morning
When you wake in the morning you have just undergone a 6-9 hour fast, meaning your muscles are literally being attacked for their amino acids, which can be converted into fuel for your body. To stop this assault on your hard-earned muscle, you need to get amino acids into your bloodstream ASAP.
PROTEIN PICK: 20 to 40 g of whey protein hydrolysate or whey protein isolate (other good options include micronparticulated whey protein, beef protein isolate, casein protein hydrolysate and soy protein isolate)
CRITICAL WINDOW 2: Preworkout
You need a rapidly digesting protein, such as whey protein hydrolysate, whey protein isolate or soy protein isolate, because getting the amino acids into your bloodstream will provide you more energy to train harder and will help prevent muscle breakdown. It will also be there at the muscles to help recovery during the workout.
PROTEIN PICK: 20-30 g of whey protein hydrolysate, whey protein isolate or soy protein isolate, within 30 minutes before workouts (other good options include micronparticulated whey protein, beef protein isolate, casein protein hydrolysate and soy protein isolate)
CRITICAL WINDOW 3: Postworkout
Time for another dose of fast-digesting protein, such as whey protein hydrolysate or whey protein isolate. Other good options include micronparticulated whey protein, beef protein isolate, casein protein hydrolysate and soy protein isolate. Whey is a particularly good postworkout protein as well because the BCAA leucine has been found to directly turn on muscle protein synthesis, which leads to better muscle growth. Plus its ability to enhance blood flow to muscle can aid recovery. Adding soy to your postworkout shake can also aid recovery by boosting GH and NO levels, in addition to its antioxidant properties that further aid muscle recovery. Although it may seem contradictory due to its very slow digestion, adding casein protein to your postworkout shake can further boost the muscle growth you get from your whey shake, as research has confirmed. Casein’s slow and steady digestion rate likely helps to keep protein synthesis turned up for longer.
PROTEIN PICK: 40 g of one — or a combination — of the above, within 30 minutes of your last set
CRITICAL WINDOW 4: Immediately before bed
Since you’ll be fasting for the next 6-9 hours, go for a very slowdigesting micellar casein or caseinate protein. This will provide a slow and steady supply of amino acids throughout the night so that your body doesn’t use the amino acids stored in your muscles for fuel. Instead it will use the amino acids from the casein protein that are in your bloodstream. Any leftover aminos that are not used for energy can go to your muscles to boost muscle growth.
PROTEIN PICK: 20-40 g of micellar casein or caseinate proteins right before you hit the hay
MIX AND MATCH
Since each protein type offers different benefits, mixing them is your best bet at most times of day. This was first seen in the research from Baylor University (Waco, Texas) that reported that males who added casein to their postworkout whey protein shakes gained significantly more muscle mass than the subjects who did not add casein to their whey shakes. This is mainly due to the fact that the fast digestion of the whey quickly turned on muscle protein synthesis, while the slow-digesting casein protein was able to keep muscle protein synthesis turned on for longer and also decrease muscle breakdown. It also may be due to the combination of aminos that each protein provides — whey is rich in BCAAs, casein is a richer source of glutamine. A third protein that would be worthwhile to add to the mix of whey and protein is soy protein isolate. That’s because soy is digested at a rate that is slower than whey but faster than casein. This could create the perfect sustained-release effect of the amino acids from these three protein sources, with whey delivering a quick dose of aminos, soy continuing to deliver aminos where whey leaves off and casein further delivering aminos where soy leaves off. Having a steady sustained supply of amino acids this way could really bolster muscle growth, particularly after workouts, or any time of day. This would be due to the fact that while whey can immediately turn on muscle protein synthesis, soy and then casein can keep it turned up for longer, as well as inhibit muscle breakdown. The net effect is greater muscle growth. In addition soy delivers a higher concentration of arginine, which can boost GH and NO levels. Consider mixing a 2:1:1 ratio of whey, soy and casein af ter workouts and whenever you have a protein shake between meals or as a meal replacement. – FLEX
– See more at: http://www.flexonline.com/nutrition/protein-powder-handbook#sthash.SKgvUUa5.dpuf.