Protein supplements such as powders and bars are often promoted as “must-haves” – especially by bodybuilders and people looking to gain muscle. They are heavily promoted in fitness magazines and many adverts go as far as to suggest that protein supplements are essential for exercise success.
While it is beyond the professional scope for any trainer or instructor to prescribe a protein supplement – that job falling to dieticians – personal trainers and gym instructors should be able to provide answers to questions from clients pertaining to this subject.
The need for protein
Protein, whether it comes in supplement form or from natural sources such as eggs, chicken, dairy or soya, is a vital ingredient for tissue repair and growth. The human body is constantly breaking tissue down and then rebuilding itself – processes called catabolism and anabolism respectively. Exercise, stress, the aging process and life in general all cause muscle tissue to break down. Muscle recovery requires protein or, more specifically, amino acids.
Amino acids are the building blocks of all tissue and the main dietary source of amino acids is protein. Protein is broken down into its constituent amino acids and they are then used to repair tissue in the anabolic process.
Too little protein, and therefore too few amino acids, can hamper muscle repair and growth in the same way that too few bricks would slow the building of a house.
Why use a protein supplement
Despite its importance, some people find it hard to consume enough protein. The typical Western diet is based on carbohydrates which are available in abundance and many of which can be consumed almost anywhere and at any time. For example, a banana provides a healthy and easily accessible source of carbohydrate.
Protein foods are generally more expensive and are not always easy to consume. It may prove problematic to cook and eat a chicken breast at work, for example.
Protein supplements make consuming protein easier as they require very little preparation, they are portable and they can be consumed almost anywhere. They can be taken between meals with minimal impact on appetite and are often manufactured with added ingredients designed to maximise anabolism such as branch chain amino acids.
What happens when you consume protein?
Protein, whatever the source, provides four calories per gram and is broken down into amino acids during the digestive process which are then used for muscle repair and growth. Some amino acids are also used for hair, skin and nail growth and components of protein are also essential for bone development.
However, many people mistakenly believe that consuming an excess of protein will automatically result in greater muscle growth.
While too little protein could inhibit muscle growth, too much will not result in accelerated results and could lead to fat gain.
Once protein requirements are met, any excess is converted to glucose and used as energy in a process called gluconeogenesis. Any glucose that is left over will, like any calorific surplus, be stored as fat. The remnant of these processes, uric acid, will be then excreted via the kidneys through the urinary system.
How much protein is required?
Daily protein requirements are dependent on two main factors: body weight and activity levels. There are lots of opinions as to exactly how much protein is required with the standard government recommendation being the lowest and bodybuilder’s and supplement company’s recommendations being the highest. This chart represents the generally accepted middle ground.
|Daily protein requirements in grams per kilogram of bodyweight|
|Recreational adult exerciser||0.8 – 1.5|
|Adult endurance athlete||1.2 – 1.6|
|Growing teenage athlete||1.5 – 2.0|
|Adult building muscle mass||1.5 – 1.7|
|Adult estimated upper limit||2.0|
Types of protein supplement
Protein supplements are very popular and are made from a very wide range of ingredients. Trainers should be aware, however, that even products with similar ingredients can vary significantly in quality depending on how they are processed and what additives are also present. If asked, trainers should steer their clients toward products that contain the fewest artificial additives including flavours, colours and sweeteners.
Whey protein – derived from dairy, whey is one of the most popular forms of protein. High in essential amino acids, it is quickly digested and utilised making it ideal for after exercise.
There are three main types of whey protein, listed in order of purity:
- Whey protein isolate
- Whey protein concentrate
- Hydrolysed whey protein
Because whey protein is derived from dairy, people who are lactose intolerant may find it causes stomach upsets and other unwanted side-effects and should choose a dairy-free protein.
Casein protein – also derived from dairy, casein digests more slowly than whey which means that it is ideal for night-time consumption.
Soya protein – soya protein is ideal for vegetarians and is made from soya beans. It does not usually contain as much protein per gram as whey.
Pea protein – a vegetarian protein that contains no lactose which means it’s ideal for those who suffer issues with dairy-derived proteins. The protein content compares favorably to other protein powders and usually delivers around 25 grams per standard serving.
Rice protein – another vegetarian/vegan-friendly source of protein, rice protein (or, more specifically, brown rice protein) is also lactose-free and provides a solid serving of good quality, easily digestible protein.
Hemp protein – hemp protein is suitable for vegans and vegetarians alike and is free from lactose and high in omega-6 (healthy), fats and fibre.
Protein is essential for muscle repair and growth but consuming more than the body actually needs will not hasten muscle growth and could lead to unwanted fat gain.
Protein supplements are useful if a client is unable to consume enough protein-rich food or needs a convenient, portable source of protein. Protein supplements are also ideal for consumption immediately after exercise when they may help accelerate post-exercise recovery.
However, supplements should not be seen as “miracle foods” or used to prop up an otherwise nutritionally unhealthy diet or poorly planned workout program. The sensible use of a good quality protein supplement may be beneficial for some exercisers but should not be viewed as essential.