Egg proteins are considered ideal proteins because their amino acid profile is used as a reference standard for comparing other food proteins. Thanks to their excellent digestibility and amino acid content, eggs are an excellent source of protein for athletes. Athletes require a higher protein intake than the current recommended daily intake (RDA) of 0.8 g / kg / day in order to achieve training adaptations and improve performance. AND (Academy of Nutrition and Dietetics) and ACSM (American College of Sports Medicine) all recommend protein intake for athletes in the range 1.2-2.0 g / kg / day, with the ISSN (International Society of Sports Nutrition) recommending 1.4-2.0 g / kg / day. Strength and power athletes are generally recommended to consume protein in the highest range, while endurance athletes should consume them in the lowest range, according to individual needs.
A whole egg contains an average of 75 kcal and 6 g of protein, but only 1.5 g of saturated fat while the egg white contains 16 kcal with 3.5 g of protein and is fat-free.
Athletes, especially amateur athletes, are often led to think “the more the better” and end up increasing proteins beyond recommendations, not evaluating the quality of the source. Egg proteins are particularly important for athletes thanks to their amino acid completeness and have been shown to significantly increase protein synthesis of both skeletal muscle and plasma proteins after resistance exercise at doses of 20 and 40 g. In addition to providing an inexpensive and high-quality source of leucine-rich proteins (0.5 g of leucine per serving), eggs are now also considered a functional food for athletes because they can provide a health benefit as well as action on performance, thanks to the presence of physiologically active components.
In fact, it is essential that athletes select the foods that must constitute their daily diet to meet protein needs, but also to safeguard their health and prevent the physiological decrease in immune function that follows intense training. The important nutrients provided by eggs are riboflavin (15% RDA), selenium (17% RDA) and vitamin K (31% RDA). Eggs are also rich in choline, a nutrient that plays a crucial role in cognitive function and in maintaining concentration, also in view of a sports competition.
The lipid content in the egg yolk does not vary significantly, but the composition of the fatty acids strongly depends on the diet of the hen. Eggs are considered a good source of conjugated linoleic acids and therefore play a role in testosterone biosynthesis, promoting an anabolic environment, which is important for endurance athletes who are sensitive to testosterone decreases observed with overtraining.
Numerous scientific evidence demonstrates an increased formation of free radicals during sports activity and this is why an athlete, both amateur and professional, must support their antioxidant defences to avoid incurring a chronic state of oxidative stress. Eggs provide an excellent source of antioxidants: carotenoids, lutein and zeaxanthin.
A note on the versatility of eggs: they can be used in most meals, at breakfast, lunch or dinner, in a sweet or savoury version, alone or included in more or less elaborate recipes. These positive properties increase athletes’ likelihood of following a diet rich in complete proteins and of high biological value.
Article by Dr. Silvia Ambrogio, Nutritionist Biologist
Bibliography
International Society of Sports Nutrition Position Stand: protein and exercise. Journal of the International Society of Sports Nutrition (2017) 14:20 DOI 10.1186/S12970-017-0177-8
Nutrition and Supplement Update for the Endurance Athlete: Review and Recommendations. Nutrients. 2019 Jun; 11(6): 1289.