The basis of sports nutritionGood nutrition not only contributes to improving performance but it also helps to ensure perfect tolerance of sports activities and promotes recovery after exercise. In this way it reduces muscular injury that can arise during exercise and help prevent poor performance.
In order to reach competitions in peak form and at the ideal weight, follow a balanced diet throughout the year, not only during training or competitions. More than anyone, you need the right daily dietary balance to avoid nutritional surpluses or deficiencies.
For sedentary individuals
Guideline daily amounts for energy :
-> 2 200 kcal/day for a woman. -> 2 700 kcal/day for a man.
During regular training
-> 2 800 to 3 500 kcal per day are necessary, even more for some endurance sports (5 000 kcal).
Calories (kcal) are provided by 3 types of nutrients in food: carbohydrates, proteins and fats.
Lipids 30 to 35%
Proteins 10 to 15%
Carbohydrates have to supply 50 to 55% of daily energy
- Drinks group: drink water as often as needed.
- Fruit and vegetables group: 5 servings per day.
- Starchy food group: at least 4 servings per day.
- Dairy products group: 3 or 4 servings per day.
- Proteins (meat, fish, eggs, etc) group: 1 or 2 servings per day.
- Group of fatty substances and sweet foods: consumption ... to be restricted!
The distribution of nutrients changes a little in comparison with the dietary balance :
Fats 25 to 30%
Proteins 12 to 15%
Carbohydrates: 55 to 60% of daily energy
In practical terms, you have to eat less fat and more "slow sugars" (pasta al dente, rice).
With regards to energy, physical exercise increases requirements but there is no standard because this depends on the individual's needs, the sport undertaken, its intensity, its duration and so on. In any case you should build up optimum energy reserves before exercising.
To do that, you need to know that during muscular activity, the body needs fuel in the form of glucose and/or fatty acids, in order to convert them into mechanical energy (food sources supply the energy needed to synthesis adenosine triphosphate (ATP), which is essential for muscle contraction (cf. p. 8).
Glucose is provided by carbohydrates and is the preferred fuel for muscles ; energy derived from glucose is the easiest for the muscle to use. The body can store a certain amount of glucose, in the form of glycogen in the muscles and liver. The body's glycogen reserves are low (250 to 400 g) and practically exhausted at the end of 30 to 90 minutes of exercise, depending on its intensity.
Fatty acids (constituents of fats) can also be used by the body to supply energy; the fatty acids used usually come from the adipose tissue. However, they cannot be used by the muscle during intense exertion.
With regards to carbohydrates, the glycaemic index (GI) of a food is a measure of its relative ability to raise glycaemia (the blood sugar level).
The lower the GI of a food, the slower but more prolonged the availability of the glucose over time; inversely, the higher the GI, the more rapidly but more transiently the glucose is available.
Example of GI :
- low GI (<40): dried vegetables (lentils, etc.), fruits such as apples or oranges, milk, yoghurt, fructose, dried apricot, etc.
- moderate/average GI (40 to 70): pasta al dente, rice, bread, fruits such as bananas or grapes, most vegetables, chocolate, ice cream, potatoes, cereal bars, raisins, etc.
- high GI (> 70): glucose, sweeter vegetables such as carrots or beetroot, honey, sweetened cereals for breakfast, waffles, etc