Protein is almost a buzz word in the sports world. No matter which sport, I frequently get asked for a high protein diet to build muscle for strength and to lose fat. With all the information on the internet, media reports and peer/ coach influences, it is difficult for any athlete to make an informed decision about their protein intake. I have realised that many people don’t really know the basics, so I’ve divided the protein section into 2 parts. In part 1, I’ll discuss why protein is essential for heath and its importance in sports nutrition, and in part 2, I will discuss protein in endurance sports before, during and after exercise.
Why is protein important
Protein is an essential nutrient in the diet. Proteins are responsible for the structure, functions and metabolism within the body. It is therefore necessary for growth and reparation of damaged cells and tissues, for the maintenance of lean muscle, nutrient transportation, enzyme production and to synthesize hormones.
Proteins are often referred to as the building blocks in the body as they are made up of chains of amino acids. The amount and type of amino acids in a protein vary. Animal sources of protein – meat, fish, chicken, eggs, milk – contain all essential amino acids and are considered complete sources of protein, whereas plant proteins – nuts and pulses – lack some of the essential amino acids and are therefore classified as incomplete. Ideally a mixture of animal and plants sources of protein should be eaten at the same time. This ensures that a good range of amino acids are regularly obtained from the diet, which is important as amino acids cannot be stored in the body, therefore regular protein intake is essential. Note: A vegetarian diet can provide all of the necessary amino acids, though care has to be taken to have a variety of non-animal sources to ensure all the amino acids are obtained.
Protein in sports nutrition
It is a misconception that the more protein you eat, the more muscle you will gain. Muscle is built/ gained through a combination of resistant training (increasing the work load of the muscle) and consuming a diet that contains enough energy and carbohydrate. If an athlete does not consume sufficient carbohydrate to meet his/ her energy requirements, the protein will be used as an energy source instead of being used to build muscle and repair tissue.
Vast research is being done to measure the protein requirements of athletes. The International Society of Sports Nutrition (ISSN), have concluded that individuals engaged in regular exercise training require more dietary protein than sedentary individuals. Obviously protein requirements will vary depending on the sport i.e. a body builder vs endurance athlete. Current research recommends that endurance athletes do have slightly higher protein requirements than the general sedentary population – 1.2-1.4g per kg body weight per day as opposed to 0.8-1.0g per kg bodyweight per day. This is to cover a small proportion of the energy costs of their training and to assist in the repair and recovery process after exercise.
As an athlete, it is important to meet your daily protein requirements, as well as to ensure that the protein is of high quality. Skinless chicken, lean meat, fish, eggs and fat free/ low fat milk are all high quality proteins which are also low in fat. Timing of protein intake is also important as it can lead to faster recovery times and improved adaptation after training. This is particularly true for triathletes doing brick training sessions and will be discussed in detail in part 2.
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