The major part of the calories (55-60%) must derive from carbohydrates (complex ones 80%, simple ones 20%), essential fuels for the muscle both during rapid and intense efforts than in endurance performances, present in daily feeding in great amounts in pasta, rice, spelt, barley, cous-cous, potatoes, bread, legumes (many of them rich in proteins as well), rusks, biscuits, corn flakes, sweet fruit, even dry sweet fruit, etc.
Lipids (fats and oils), important energy source for sports in which aerobic metabolism is greatly involved as those of long duration, should bring 25-30% of daily calories. The main lipid source, in a Mediterranean diet, is extra-virgin olive oil (the foundation of Mediterranean diet); the remaining part will came from those present foods (the so-called “hidden fat”) as in meat and meat products, milk and cheeses, eggs, oily dry fruits, oilseed etc. and, between seasoning fats, butter (better avoid margarine, often rich in industrial trans fatty acids, a real poison). As previously mentioned it is advisable to avoid fast food and industrial products (in particular bakery products such as cookies, snacks, cakes, croissants, pastries, French fries, fried chicken etc.) because lipids present in these foods, unless clearly specified in the package, are never extra-virgin olive oil but mostly palm or coconut oil and often partially hydrogenated vegetable oils as well.
The daily lipid intake must not be less than 20% of daily calories because it could occur an insufficient intake of essential fatty acids and fat-soluble vitamins; moreover, considering athletes with very high energetic demands, their deficiency would cause too much abundant meals (lipids 9 Kcal/g, carbohydrates 4 Kcal/g, so more than double) and not very desirable (fats increase palatability of foods).
The remaining calories (12-15%) come from proteins, both of animal origin (meat, fish, egg, milk and dairy products), 2/3 of the total, and vegetal origin (legumes and cereals), the remaining 1/3.
Jeukendrup A.E. Nutrition for endurance sports: marathon, triathlon, and road cycling. J Sport Sci 2011:29;sup1, S91-S99. doi:10.1080/02640414.2011.610348
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