How whey promotes muscle growth

What athletes call the whey is a trade name that simply refers to milk whey, one of its two proteins, along with casein. A protein powder present on the food and sports nutrition market since the late 1990s, whey is extracted from milk using filters (microfiltration and ultrafiltration) and then dried before being packaged into powder. With the development of high-precision filtration processes, the nutritional quality obtained for this protein has greatly improved. Flavored, whey powder is consumed worldwide by bodybuilders for promote muscle development . Apart from sports nutrition, this milk protein powder is also found in countless prepared meals with a much lower protein concentration than for athletes.

In food, it is added as a texturizer, rather than for its protein value. Today, whey can be produced in very large quantities at a controlled cost while its exceptional nutritional qualities are preserved during its manufacture. Processed food by nature Made from milk, the resulting protein powder is perfectly pure, with no added molecules, adjuvants or additives that are harmful to health. Technically, it is therefore a pure protein packaged in powder form, for use by athletes in bodybuilding or high-protein diets.

The biochemical foundations of whey

In itself, “whey” is a peptide protein derived from water-soluble cow's milk. This quality makes it a light protein that is easily assimilated by the body. Biochemically, the whey in milk and its solubilized peptides will therefore be quickly assimilated by the newborn calf. This allows it to quickly strengthen its immunity and provide it with essential amino acids necessary for its growth. The principle is the same for breast milk proteins. In contrast, the casein in milk will be digested slowly by the stomach, allowing the body to be fed gradually over several hours. But let's go back to the composition of whey and its peptides...

Composition of whey and its key elements

Whey is composed of a combination of peptides that act positively on the immune system from calf to cow's milk or infant milk in humans. It is the first form of protein consumed by the young, just after colostrum. Thus, whey protects the immune system and nourishes the body. Retaining more than 90% water, the remainder is composed of peptides such as beta-lactoglobulin, bovine immunoglobulins, as well as bovine serum albumin, alpha-lactalbumin, glycomacropeptides and lactoferrin. These peptides are themselves made up of the nine essential amino acids, key nutrients for muscle growth for bodybuilding athletes. Remember that these are phenylalanine, threonine, histidine, valine, leucine, isoleucine, methionine, tryptophan and lysine. Each of these amino acids has many roles to play in the body on an individual level. Combined into peptides, they have even more functions. Combined into proteins, they perform even more roles, including the deep structure of your muscles.

How does whey have a positive effect on muscles and their growth?

The advantage of whey (or whey if you prefer the English term) is that it is assimilated very quickly. Passing through the stomach without being degraded much, the peptides quickly cross the intestinal barrier to feed the body and muscle cells, among others... The fact that it is completely soluble in water gives it this ease of assimilation, with a rapid distribution of the amino acids that compose it. When you make a whey shake with water, you rehydrate the protein, a bit like finding the original liquid mixture but without the casein. You therefore benefit from all the nutritional principles of the protein.

Among these, the essential amino acids directly participate in the maintenance and growth of muscle fibers. Similarly, whey also provides non-essentials since they are just as necessary for metabolism. They participate in energy synthesis as well as strengthening the immune system. Even if considered non-essential, your body will not spend energy and enzymes to synthesize amino acids essential from non-essential ones if it receives them naturally. This process remains very partial since you cannot constantly synthesize non-essential amino acids at the expense of essential ones. This also explains why complete proteins are essential to the human body. Still, whey helps strengthen immunity by providing the peptides we mentioned. This element is crucial for athletes since it is difficult to stimulate muscle growth if you are sick. We will talk about this later…

Scientific research and study results …

Scientific and clinical studies on whey protein are particularly numerous given that it is an exceptional protein in terms of nutritional quality. In parallel with food, the sports nutrition market has grown significantly since the commercialization of this milk protein. The growing growth of the market and scientific research have therefore evolved in parallel. It was during the 1990s that the evolution of sports nutrition and scientific research will be the highest, both for whey and for creatine. Whey protein will be studied in particular to determine if it is able to stimulate muscle growth .

As for creatine, its ergogenic character (which stimulates athletic performance) will also be the subject of numerous in-depth clinical studies with athletes of all levels. For whey, the results of clinical studies tend to vary, particularly depending on many criteria such as the level of experience of the subjects, their age, their physical condition, their training or their diet. In the end, most clinical studies will tend to conclude that for this milk protein, the increased presence of essential amino acids ( Church et al. 2020 ) and the diet daily routine of athletes are among the most determining criteria. On the other hand, the question of sarcopenia is also put forward by many researchers given the exceptional nutritional quality of this protein as well as its ease of assimilation ( Li CW et al. 2019 ). Its exceptional concentration of essential amino acids has motivated numerous clinical studies, both for athletes and for aging sedentary people. This is particularly the case for branched-chain amino acids and L-leucine in particular.

Key studies on whey and muscle development

To date, just over 200 studies and meta-analyses have attempted to determine whether whey stimulates muscle development. The study by Church et al. (2020) demonstrates that the increased presence of essential amino acids (notably BCAAs and leucine ) play a determining role in protein synthesis, as stated above. Other clinical studies highlight the fact that whey, when accompanied by other essential nutrients (vitamin D, creatine, etc.), more easily leads to an increase in lean muscle mass ( Rondanelli et al. 2016 ), in particular to combat the loss of amino acids from muscle fibers (catabolism). Let us add that the question of amino acids is important but that whey also presents a unique interest due to its content of peptides whose ameliorating role on the immune system has been demonstrated (Madureira et al. 2010)

Similarly, whey peptides have been studied in animals for their effects on muscle growth or its probable anti-catabolic effects ( Wu et al. 2022 ). Some researchers have also studied the impact of whey on supporting muscle mass and health ( Devries, Philips 2015 ). Naturally, the role of whey on weight gain and in particular, the glycemic index, have been studied by researchers ( Giglio, Lobo, Pimentel 2023 ). Other research, directly or indirectly linked to muscle development, has been developed on the potential of whey to stimulate the assimilation of glycogen by the liver and muscles ( Morifuji M 2005 ). In direct connection with the hypertrophy of skeletal muscle fibers, researchers have analyzed the potential of whey to stimulate the proliferation of satellite cells to strengthen muscles during post-exercise recovery ( Farup J. et al. 2014 ).

Analysis of data and conclusions from scientific and clinical research on muscle development

The majority of scientific and clinical articles on whey protein highlight several essential data for athletes. This research has shown that the concentration of essential amino acids in whey significantly contributes to the development of muscle mass in athletes. Elements related to the immune system and the gut microbiota have also been highlighted. Indeed, the issue of immune strength is essential for bodybuilding or endurance athletes who perform high-intensity training. In this regard, studies have shown that the body's defenses are reduced after this type of intense training. Providing peptides after a workout would help preserve the body of athletes. According to the research findings, whey protein would therefore have many positive aspects for athletes who want to gain lean muscle but perhaps also for sedentary people who want to maintain their health. Note that the results of clinical studies are valid for bodybuilding practitioners but also for endurance athletes. Both forms of high-intensity exercise were studied by the researchers.

Whey and supplementation regimes

Even sedentary people would fully benefit from the advantages of whey since a minimum intake of 0.8 to 1 gram of protein per kilogram of body weight is necessary to maintain the integrity of biological functions, muscle mass , the immune system, and a considerable number of organic processes. However, even people who pay little attention to the quality of their diet are likely to fall short of this minimum quota several days a week. A whey shake, even two to three times a week, would already be a rational supplement as part of a diet related to the health of the body.

On this subject, we know that the body constantly regenerates new proteins with the amino acids it has available. However, a chronic lack of dietary protein will eventually damage the body over time, given that cellular and organic aging leads to a slowdown in protein assimilation. A chronic deficiency in nitrogenous elements weakens the body over time, on a structural, organic and immune level. An optimal protein intake (generally greater than 0.8 grams/kilo of body weight) can only be recommended, even for sedentary or inactive people...

Protein intake differs depending on whether you are doing endurance or strength training.

In endurance or team sports athletes, an intake equal to 1.2 grams per kilo of body weight would be beneficial to their sports performance and post-exercise recovery . In this case, a whey shake could already be designed and framed in a supplementation regimen including a protein, a multivitamin as well as a controlled intake of minerals and electrolytes, mainly magnesium, potassium and essential trace elements. Here too, two to three milkshakes per week can be considered, especially if the diet of the endurance athlete does not always provide sufficient protein during meals. Indeed, it will be necessary to take into account the fact that the muscle mass of these athletes must be maintained in order to maintain or improve athletic performance. Then, the nutritional intake of carbohydrates and fatty acids will participate in the release of energy during exercise.

For bodybuilders and strength athletes, maintaining an average daily intake of between 1.6 and 2.5 grams of protein per kilogram of body weight is considered sufficient when it comes to stimulating Gain muscle mass and strength . To this end, if you eat 3 to 5 meals a day, make sure to include 40 to 50 grams of protein per meal. Even breakfast should be high in protein. Eggs, cereal with milk, turkey, ham, or other plant-based protein sources are ideal at this time of day.

Whey Protein Intake Protocols for Bodybuilding

Generally speaking, a whey protein shake before or after a strength training workout will facilitate energy release and post-exercise recovery. If you take your whey protein one hour before training, your body and muscles will have an optimal supply of energy during exercise since the amino acids will be easily converted into glucose and then into ATP. Even if your meals allow you to replenish your glycogen stores, an additional intake of amino acids before training will facilitate energy release during the first sets of your workouts. Whey protein prevents catabolism during exercise. If you take it before your workout but are looking to gain strength, add 3 grams of creatine monohydrate to your shake is an effective supplementation strategy.

Taking a whey shake has several benefits in terms of muscle development. On the one hand, because whey has a very high concentration of essential amino acids, without any deficiency. This is particularly the case for BCAA and leucine in particular. The ultimate anabolic amino acid, whey protein has a particularly high leucine content. This is a characteristic it shares with egg albumin. However, whey protein's bioavailability is even higher than that of eggs, which are considered the benchmark with a score of 100. Naturally, whey powder, concentrate, or isolate also provides an equally high quantity of non-essential amino acids.

Whey protein taken after intense training reduces post-exercise catabolism

On the other hand, whey protein will be quickly converted into muscle and liver glycogen, a significant advantage when it comes to reducing catabolism following intense strength training, endurance training, CrossFit, or other high-intensity physical activities. This is a key element that should not be overlooked when you are looking to promote muscle development and strength gain. Indeed, recovery after exercise necessarily involves rapid restocking of glycogen, even before the muscle fibers damaged by exercise regain mass, volume, and strength.

Interactions with other supplements useful for muscle development

Logically, bodybuilders will combine whey with creatine in order to stimulate muscle strength during exercise. It should also be noted that creatine can be taken after exercise because it also promotes recovery after exercise ( Sundell 2011 ). In addition, good nutritional and sports supplementation should also start with taking a good multivitamin. Remember that B vitamins (thiamine, flavin, niacin, pyridoxine, etc.) are necessary for the assimilation of proteins as well as for the release of energy from amino acids, but also from carbohydrates and fats. Enzymes such as NADH and FAD also come from the Vitamin B3 and B2 . Specifically, these are essential enzyme coenzymes. They convert glucose into ATP. Lacking these vitamins prevents you from getting 100% of the protein, carbohydrates, and fats you consume.

Also consider the role of magnesium in muscle contraction and energy. Finally, it is certainly unnecessary to recall the importance of vitamin D on muscle strength. Its role on exchanges between the phosphocreatine and ADP have been clearly demonstrated. Similarly, vitamin D is necessary for regulating the immune system as well as bone strength. In this regard, this essential vitamin works in synergy with vitamin K, a micronutrient that should also not be overlooked. And if the muscles are put under severe strain, this is also the case for bone mass, which must withstand high and repeated loads during the heaviest bodybuilding exercises.

Practical implications and advice

If you're using whey protein to boost muscle growth, you should also know that it will only help you if you're consistent over time. Like all forms of dietary supplements, regularity and consistency in taking them over several weeks, or months for a protein, is absolutely essential if you want to get any positive results from them over time. If you're thinking of taking a whey protein shake once every three days and hoping it helps, you're wrong. Whey protein is meant to be integrated into your diet in the medium and long term.

When you practice a sport like high intensity weight training Whether you're working out at a gym or exercising at a high volume, it's clear that your body and muscles need protein consistently to recover and grow. Scientific research has shown that intense training can take 3 to 5 days to fully recover. Consuming protein and protein-rich foods should therefore be done regularly. A protein powder isn't a miracle product, but it provides the essential building blocks for long-term muscle rebuilding. Let's just say it helps you maintain your daily protein intake while minimizing calorie intake. A functional food, a protein powder provides only pure protein. So, for 25 grams of powder, that's about 100 calories.

A light protein rich in amino acids for muscle development…

The question of taste is also important when it comes to protein powder. Whey is a very light protein that necessarily requires to be associated with a texturizer (usually lecithin) as well as flavorings to be appreciated over time. Since it is a more or less long-term consumption, you must also be able to vary the flavors of your protein over time. In reality, the question of taste is one of the two determining criteria in terms of loyalty to a whey powder, along with nutritional quality. Obviously, the question of taste has been particularly worked on at YAM Nutrition in order to keep you loyal to our Whey Isolate . Isolate of French origin, you benefit from a native whey isolate whose taste is just as appreciable, even for several weeks.

Optimal dosage and timing of consumption

When it comes to the optimal dosage of whey to add to your shake, there are several criteria to consider. First, you must consider your body weight and then, the grammage per kilogram of body weight you want to achieve. Naturally, if you weigh 70 kilos, you will need to consume less protein than an athlete who weighs 90. Let's say you are set on 2 grams of protein per kilogram of body weight. For a 70 kilo athlete, this represents a quota of 140 grams per day. For a 90 kg bodybuilder, this represents 180 grams/day. To give you a more precise idea of ​​the grammage to obtain, let's say that scientific research has determined that an intake of between 1.6 and 2 grams/kilo of body weight helps maintain muscle anabolism. This amount of protein then stimulates muscle development and strength. As for timing, let's just say that most bodybuilding athletes tend to take a shake of whey between meals on rest days while they take one before exercise and just after to promote the development of muscle mass.

Recommendations based on the type of physical activity

As we discussed, your protein nutritional needs depend on the sport you practice. However, you should keep in mind that if your workouts are particularly intense, your muscles will suffer micro-tears that you will need to repair with amino acids. Your protein needs for muscle development will therefore increase, either modestly if you do an endurance sport or more intensively if you do weight training. Indeed, bodybuilding directly damages muscle fibers in a partial way. Your protein needs will therefore be higher compared to longer-term physical activity.

Both protein and carbohydrates stimulate muscle development and strength

While protein is necessary to strengthen muscle fibers after intense strength training, so are carbohydrates. These essential elements are your primary energy reserves during training. Carbohydrates also help block the loss of muscle fibers after a workout. Indeed, muscle fiber recovery and synthesis cannot occur if glycogen does not return to the trained muscles. In fact, carbohydrates block catabolism, while proteins trigger anabolism after weight training.

A whey isolate or concentrate after training, a good move for post-exercise recovery .

Under these conditions, taking a whey shake after training will play a dual role. First, to replenish glucose and store it as glycogen, and second, to reactivate muscle building after weight training. This also explains why carbohydrates are so important, even for bodybuilders. Protein can't do everything on its own, especially if your carbohydrate intake is insufficient. Then, it's up to you to find the best balance between carbohydrates and protein to stimulate muscle development in the most effective way. In any case, if your weight training is intense, consuming between 3.5 and 5 grams of carbohydrates per kilogram of body weight will help you achieve better athletic performance. Don't forget the good fatty acids, especially omega 3 and 9. Then, protein will allow you to build muscle over time...

Selected bibliography

Church DD et al. Essential Amino Acids and Protein Synthesis: Insights into Maximizing the Muscle and Whole-Body Response to Feeding , Nutrients. 2020 Dec 2;12(12):3717.

Devries MC, Phillips SM. Supplemental protein in support muscle mass and health: advantage whey. J Food Sci. 2015 Mar;80 Suppl 1:A8-A15.

Farup J, Rahbek SK, Knudsen IS, de Paoli F, Mackey AL, Vissing K. Whey protein supplementation accelerates satellite cell proliferation during recovery from eccentric exercise. Amino Acids. 2014 Nov;46(11):2503-16.

Giglio BM, Lobo PCB, Pimentel GD. Effects of whey protein supplementation on adiposity, body weight, and glycemic parameters: A synthesis of evidence , Nutr Metab Cardiovasc Dis. 2023 Feb;33(2):258-274.

Li CW, Yu K, Shyh-Chang N, Li GX, Jiang LJ, Yu SL, Xu LY, Liu RJ, Guo ZJ, Xie HY, Li RR, Ying J, Li K, Li DJ. Circulating factors associated with sarcopenia during aging and after intensive lifestyle intervention. J Cachexia Sarcopenia Muscle . 2019 Jun;10(3):586-600.

Madureira AR, Tavares T, Gomes AM, Pintado ME, Malcata FX. Invited review: physiological properties of bioactive peptides obtained from whey proteins , J Dairy Sci. 2010 Feb;93(2):437-55.

Morifuji M, Sakai K, Sanbongi C, Sugiura K. Dietary whey protein increases liver and skeletal muscle glycogen levels in exercise-trained rats , Br J Nutr. 2005 Apr;93(4):439-45.

Rondanelli et al. Whey protein, amino acids, and vitamin D supplementation with physical activity increases fat-free mass and strength, functionality, and quality of life and decreases inflammation in sarcopenic elderly , Am J Clin Nutr. 2016 Mar;103(3):830-40.

Sundell J, Hulmi J, Rossi J. Whey protein and creatine as nutritional supplements , Duodecim. 2011;127(7):700-5.

Wu X, Yu X, Zhu N, Xu M, Li Y. Beneficial effects of whey protein peptides on muscle loss in aging mice models . Front Nutr. 2022 Sep 9;9:897821