In the human organism, proteins have a mainly plastic / structural function because they provide most of the "bricks" with which we are made. In addition to the importance of a nutritional nature, the intake of proteins as supplements, is indicated in the sports field every time you want to ensure an increase or maintenance of lean mass at the expense of fat mass.
The athlete or sportsman engaged in a weight training program, aimed at increasing explosive or maximal strength, such as the one looking for muscle hypertrophy, usually combines a portion of proteins ranging from 1 to 1 to their nutritional program. 5 g / kg and 2.5 g / kg per day.
While traditional protein sources, such as white meats, fish and eggs, are taken at main meals, without particular distinction, in the case of powdered protein supplements (derived from milk) the attention has shifted not only to the quality of ingredients but also on the timing of intake.
The market offer of these products is essentially focused on supplements composed exclusively of whey proteins (isolated, ultra-filtered, hydrolyzed and concentrated) or supplements based on casein and / or mix of these with whey proteins, in the most disparate proportions ( 80% -20%, 50% -50%, 75% - 25%) according to the manufacturer and the purpose of the product.
The whey protein
Whey proteins are globular proteins, rich in essential amino acids, in particular in branched chain amino acids, they also contain the glycomacropeptide fractions, characterized by a marked neo-glucogenic function (production of glucose starting from glucogenic amino acids, including glycine, glutamine, valine and isoleucine). The studies carried out on the use of whey proteins in sports have shown a greater ability of the same, compared to other protein supplements, to stimulate protein synthesis, especially if taken in the post workout phase, in conjunction with carbohydrates with a medium-high glycemic index ( maltodextrin, vitargo and dextrose).
Whey proteins are naturally rich in cysteine, which stimulates the production of glutathione (GSH), an endogenous substance with antioxidant potential. The rate of assimilation of whey proteins is so high that, a few minutes after intake, the levels of leucine in the blood (biochemical marker of food protein metabolism NDR) rise, leaving the body with a complete supply of amino acids to stimulate nourishment. cellular and protein synthesis.
Caseins
Caseins and caseinates are micellar proteins, composed of all essential and non-essential amino acids, but above all with a high content of glutamic acid, which converts into glutamine. The biological value (VB) of caseinates is 90, therefore quite good when compared to that of egg albumin or whey protein which corresponds to 100. The functional advantage of using a powdered casein supplement derives from the fact that their digestion it provides a medium-high amino acid intake that lasts several hours. This condition confers an anti-catabolic action to this type of protein, and therefore it is recommended to use it at night before going to bed or as a protein snack away from main meals. It is generally recommended to use a portion of caseinates especially when following a food program aimed at muscle definition; in this context, caseins are more beneficial because in addition to giving greater satiety, they reduce the oxidation time of amino acids in the blood, promoting a correct metabolism. Unlike the whey proteins in this food context are converted for the most part into glucose (hepatic neoglucenesis) before even reaching the muscles.
Advice for use
The above information must not be interpreted in contradiction with each other, the athlete is advised to take protein supplements according to specific needs, and to summarize a general picture we can indicate the following.
Breakfast: protein snack 30-40 g of powder based on whey proteins and caseins (60% - 40%), then that after the prolonged night "fast" the muscles need a fast amino acid supply, however you must also provide the same to the early hours of the day.
Post Workout: protein snack 30-40g of powder based on whey proteins (isolated and / or hydrolyzed), because the hormonal stimulus induced by "weight training acts on the so-called" anabolic window ", lasting about 2 hours, in which the muscles begin the recovery phase, and are in debt of amino acids and sugars. In this case we also recommend the intake of sugars and creatine.
Before going to bed: 20-30g protein snack based on caseinates, because the real need is to ensure a supply of amino acids for as long as possible, considering that the R.E.M. coincides with the secretion of growth hormone, which carries out a marked anabolic action, especially in conjunction with the presence of amino acids in the bloodstream.
Quality protein supplements