Proteins

Basic nutrition: proteins
The bottom layer of the sports nutrition pyramid contains basic nutrition. These are ordinary products that you can buy in any supermarket: vegetables, fruit, dairy, nuts, fish, eggs, whole wheat bread, etc. These form the basis of healthy sports nutrition. In this blog, the focus is on products that contain proteins. What are proteins, where are they found and why are they important for you as an athlete?

What are proteins?
Proteins are building blocks for the body. Proteins consist of long chains of amino acids. There are 22 different amino acids, of which 9 are essential. Essential means that your body cannot produce them itself. Suppose: you do not get enough of the non-essential amino acid through your diet, then your body can produce it from other amino acids. But if you do not get enough of the essential amino acid leucine, for example, a deficiency occurs, which means that your body is not sufficiently able to build new protein structures. After all, you need all the building blocks for this. Semi-essential means that the body can only produce these insufficiently in exceptional cases (such as illness). Proteins differ from carbohydrates and fats in the type of atoms they contain. Carbohydrates and fats only contain C (carbon), H (hydrogen) and O (oxygen) atoms. Proteins also contain an N (nitrogen) group. This makes them less efficient for your body to use as a fuel source.

Where do proteins come from?
Animal products are rich in protein. Meat, fish, chicken, eggs, milk, yoghurt, cottage cheese and cheese contain a considerable amount of protein per serving. The lean varieties (low-fat yoghurt, chicken, low-fat cottage cheese, lean meat) contain more protein per 100 grams than fattier products. There are also good sources of vegetable proteins. Think of legumes such as lentils, peas, beans, nuts, corn and grain products such as quinoa. The difference between vegetable and animal products is the amino acid composition. Animal protein sources are complete. This means that they contain all the amino acids that a person needs. Animal protein sources often have a higher PDCAAS (protein digestibility corrected amino acid score) value than vegetable proteins. The PDCAAS value indicates the amount of essential amino acids, corrected for the digestibility of a protein. Vegetarians do well to combine different vegetable products with each other to get enough essential amino acids. The only complete vegetable protein is soy. That is one of the reasons why soy milk is a more complete substitute for milk than rice milk, for example, and is often used in meat substitutes such as vegetarian burgers.

What is the function of proteins?
Although proteins provide energy (just like carbohydrates 4 kcal per gram), your body prefers not to use proteins as an energy source. Proteins are primarily a building block for the cells of your body. Think of building muscle mass, but also of healing wounds or recovery after an injury. In addition, proteins play an important role in building hormones, have a transport function (for example to transport oxygen) and ensure that the fluid balance is maintained.

Your body can use proteins as a fuel source, but this is neither a desirable nor an efficient process. It actually means that you do not have enough fuel (carbohydrates) at your disposal and that you are therefore breaking down muscle mass. This situation can occur during fasting and very long-term efforts such as a triathlon. The breakdown of the body's own proteins is accompanied by the release of an ammonia smell, because the nitrogen group has to be disconnected. If you smell such a smell, you would do well not to continue your workout, but to first take in fuel. Of course, it is better to avoid it altogether and to take in sufficient fuel before your workout (and possibly during).

You need 0.8 grams of protein per kg of body weight per day. If you weigh 70 kg, this amounts to 56 grams of protein per day. The more often and intensively you exercise, the more protein you need. You don't have to overdo it. Only in competitive bodybuilders has it been shown that an intake of 2.5-3 grams of protein per kg of body weight can be useful. For 'normal' athletes, it varies from 1.2 grams (endurance sports) to 1.8 grams (strength sports) per kg of body weight. Incidentally, you can easily get these amounts from your normal diet, no shakes or supplements are needed for that.