As an athlete training hard to reach your goals in strength, muscle mass and fat loss, you are probably well aware of the importance of optimal nutrition. The body needs nutrients in the right proportions to provide building blocks, supporting recovery and your immune system. Most of you are aware of the important role protein plays in your diet. Elite athletes, powerlifters and bodybuilders are known to ingest up to 4-5 times their bodyweight in grams of protein, so 400g of protein per day is not unheard of. A protein surplus is necessary if you want to add muscle mass and strength, but on a diet to lose body fat, protein needs actually increase to prevent the loss of lean body mass! A good recommendation for most of you who want to get optimal results from your training is 2-2.5 times your own bodyweight in protein, so 160-200g of protein per day for an 80kg male and 120-150g of protein per day for a 60kg female. If you follow a low-carb diet you might want to increase protein further in some cases. As a personal trainer, I have seen that the average protein intake is usually closer to half of this recommended range when I start working with my clients, so switching to more lean meats, fish and eggs while adding high quality protein supplements to the diet rectifies this issue immediately. Protein supplements may not be needed if you eat plenty of food, but since it is so quick, easy, convenient and cheap, I think we can all agree that a couple of protein shakes per day are a delicious and tasty alternative to eating all the time. We will have a look at some of the commercially available protein sources.

Whey protein is a milk-derived protein that is highly bioavailable, fast acting, and inexpensive, and it has many qualities that make it superior to most other protein sources, especially for the athlete. It also provides an easy way for athletes to meet their high protein needs.

As far as protein quality goes, whey is top of the line. Various methods have been used to evaluate protein quality. The most well-known is biological value (BV). This is a measure of how much of the absorbed protein that is retained for use. Egg protein, which was originally thought to have the highest bioavailability of any protein, is the standard reference with a bioavailability of 100. Whey protein concentrate has a bioavailability of 100 as well, compared to around 90 for milk and 70-80 for meat.

PDCAAS (protein digestibility-corrected amino acid score) is a more recent method of determining protein quality, and is based on whether or not a protein meets the human amino acid requirements (hence, incomplete proteins have lower scores) as well as how digestible the protein is. The maximum PDCAAS is 1.00, and whey protein has a PDCAAS of .99-1.00.

Studies support the idea that whey protein exerts an anabolic response when taken before and after workouts. While exercising and in the following hours, protein breakdown and synthesis both increase drastically, and a readily available protein source is essential to changing the initially catabolic response from exercise into an anabolic one. Being a fast acting protein, whey has the capability to stimulate protein synthesis at the most crucial times. Whey protein has many other benefits, as it contains many beneficial growth factors, toxin-binding factors, antimicrobial peptides, probiotics, and immune regulatory factors. Whey is in fact being researched in the areas of immune support, cancer prevention, digestive tract health, hypertension, and bone strength, due to its unique properties that are absent from other protein sources.

Note that type of protein also is extremely important. Whey protein concentrate (WPC) is at best 80-85% protein by weight, and contains undesirables such as lactose and fat. Some actually contain less than 70% protein, with a carb and fat content as high as 5-10%, the rest being inert substances not useful to the body. Lactose is the sugar found in milk and combined with the unhealthy saturated fat in this concentration it is not something you would want to ingest every day. Many experience digestive problems from WPC as a consequence. WPC is the cheapest protein source, and the food industry uses it as an additive in things like candy, cakes, biscuits, and soups. Those who sell it as a sport supplement has an extremely high margin on it, making it very profitable for them, but not for the consumer.

Isolates, on the other hand, are a product of superior processing techniques which removes the lactose and fat content, providing an end product of virtually pure protein, while retaining the positive growth factors and immune support factors inherent in milk. The protein content is usually around 90% or even higher, and fat and carbs in the 0-1% range. This is the best protein source for an active individual who wants to supplement his diet with a high quality product. Whey protein isolate is usually more expensive, but since you also get a higher protein concentration and higher quality product, it is well worth the price. Isolates are often used in clinical and medical treatments.

Another isolate product is milk protein isolate, which contains a natural mixture of 20% whey and 80% casein. Milk protein isolate combines a fast protein with a slow protein, just as nature intended it, and it is a very cost efficient and high quality protein source.

Micellar casein is the natural, undenatured form of casein found in milk. It is separated from milk by means of ultrafiltration, without the use of chemicals, which increases the amount of bioactive milk peptides that support immune function as well as enhance muscle growth. A property of micellar casein is that it may have the ability to form a "gel" in the gut. This makes it an extremely slow digesting and rich protein source that continues to feed your muscles long after the amino acid pulse from whey is gone. While whey protein may increase protein synthesis to a very high degree, higher than casein, scientists are now recognizing that micellar casein is very important in preventing muscle breakdown. Additional research is demonstrating that the slow and sustained release of amino acids from micellar casein can cause a 'timed release' trickle of amino acids into the bloodstream which can last for as many as 7 full hours after ingestion. It offered a strong anti-catabolic effect not noticed with fast digesting whey protein, and actually provided an overall positive net protein balance as a result. Undenatured, the way nature intended it, Micellar casein contains a higher content of bioactive milk peptides which not only enhance muscle growth but modulates regulatory processes such as support for the immune system and proper digestion.