Health, Food & Diet

I was just at a sports science conference, held at a university where one of the key focus areas is strength and conditioning and one of the “goodies” in the show bag we were given was a protein shaker. I’m sure the majority of the conference knew what it was, but I was quite surprised to hear that some people had absolutely no idea why the bottle had a spring rattling about inside. Now, don’t get me wrong, it wasn’t a strength and conditioning conference, but I had expected that in a not-so-distant field of science, that everyone would have known exactly what a protein-shaker was. The point of my preamble is this – there are many people who don’t know about how, when and why you should (or should not) use protein shakes, so there isn’t any harm in asking.

What is a protein shake?

Protein shakes are made up by mixing a flavoured powder, often composed of either whey or soy protein, with water or milk. These may come in a concentrate or isolate form. There are many different protein powders on the market, each varying in their sources of protein, their percentage of protein, and flavour. If you are planning on starting use protein shakes as a supplement, it’s important to know what you are trying to achieve and to find one that is suitable.

So what’s the difference between a protein concentrate vs. isolate powder?

Protein concentrate and protein isolate powder differ in the creation process and as a result, the nutrients provided. Protein isolate essentially requires further processing of the protein concentrate through micro-filtration and as a result, the percentage of protein per serving is greater. If you consider whey protein, concentrate powder will include some additional nutrients including carbohydrates like lactose and milk fats. Because of these additional nutrients, concentrates have more overall kilojoules per serving and a whey protein isolate may be a better option for those who are ‘calorie-conscious’.

If isolate powder gives more protein per unit, does this make it better?

Not specifically. If we take whey protein example from above, concentrate powders include fats and carbohydrates in addition to the protein – but these nutrients are considered to include beneficial constituents such as growth factors, antimicrobials and antioxidants. As protein isolates undergo greater processing, they lose some of these health-promoting compounds; however, the biological value (quality) of the protein is higher and they are more rapidly absorbed, which can make them a popular choice for post work out consumption. It is unlikely that you would be able to conceivably tell the difference between a concentrate and isolate from a performance perspective. Before you chose between, I’d suggest talking to a specialist about any allergies, dietary restrictions and goals you wish to achieve.

How and why do protein shakes help build strength and promote muscle hypertrophy?

Studies have shown that starting up an intensive strength-training program increases the dietary protein needs of an individual. Resistance exercise cause little tears in the muscle and amino acids (the building blocks of muscle) are required during the repair process. Providing the body with an adequate supply of amino acids ultimately helps with the ability to build and maintain muscle mass.

Protein powders have a strong profile of amino acids. A good protein shake will have a higher biological value than most other common sources of protein (e.g. eggs, meat). In addition, protein shakes are easily absorbed which allow the beneficial nutrients to be readily processed once ingested.

The timing of protein intake post exercise is important and research indicates that there is a strategic window for the use of protein supplements with essential amino acids post exercise. Supplementation during this time is believed to help enhance the response to exercise by providing a higher stimulation of protein synthesis. Protein shakes make a really effective and convenient way to get these nutrients quickly into the body.

I’ve heard protein shakes can help you lose weight..?

In addition to the benefits of aiding muscle synthesis, protein supplementation has been shown to have other benefits such as suppressing the appetite, supporting fat burning, and improving insulin sensitivity. However, protein shakes are not a magic cure for weight loss, and should be used in conjunction with a well-structured resistance program and adequate diet. Remember to take account of the content of your protein powder, as some will have higher concentrations of carbohydrates and fats. Additionally, if you are mixing it with milk, you’ll need to take into account the energy content of the milk too.

So, do I need to drink them?

Strictly speaking, whilst increased dietary protein consumption is needed when undertaking a resistance program, you do not need to get this from protein shakes. You can get the requirements from eating a planned diet that is higher in protein.