Alban a écrit:Ce qu'il y a de bien avec les étudessur les besoins en protéines, c'esty que si on se donne une valeur à l'avance, par exemple 1,05 g/kg ou 2,43 g/kg, on a forcément en trouver une qui dit que c'est cette valeur qu'il faut.
Et de même, on a sur et net et les forums des guignols qui nous disent la même chose.
Pour une étude un peu plus sérieuse prenant en compte plusieurs décennies de recherches sur le sujet : "The protein book" de Lyle McDonald.
Dans ce cas la je préfère lire Aragon et al. au lieu de lire les conclusions d'un fou bipolaire troublé qui charge +50 USD pour un ebook.
D'ailleurs la quantité de protéine a ingérer varie considérablement selon plusieurs facteurs qui sont mentionné dans cet article:
Determining macronutrient intake
Protein
Adequate protein consumption during contest preparation is required to support maintenance of LBM. Athletes require higher protein intakes to support increased activity and strength athletes benefit from higher intakes to support growth of LBM [5,22-28]. Some researchers suggest these requirements increase further when athletes undergo energy restriction [13,16,22,28-33]. Furthermore, there is evidence that protein requirements are higher for leaner individuals in comparison to those with higher body fat percentages [7,33,34].
The collective agreement among reviewers is that a protein intake of 1.2-2.2 g/kg is sufficient to allow adaptation to training for athletes whom are at or above their energy needs [23-28,35-38]. However, bodybuilders during their contest preparation period typically perform resistance and cardiovascular training, restrict calories and achieve very lean conditions [2-6,17-21]. Each of these factors increases protein requirements and when compounded may further increase protein needs [33]. Therefore, optimal protein intakes for bodybuilders during contest preparation may be significantly higher than existing recommendations.
In support of this notion, Butterfield et al. [22] found that male athletes running five to 10 miles per day during a slight caloric deficit were in a significant negative nitrogen balance despite consuming 2 g/kg of protein daily. Celejowa et al. [39] showed that five out of 10 competitive weight lifters achieved a negative nitrogen balance over the course of a training camp while consuming an average protein intake of 2 g/kg. Out of these five, as many as three were in a caloric deficit. The authors concluded that a protein intake of 2–2.2 g/kg under these conditions only allows for a small margin of error before nitrogen losses occur.
Walberg et al. [32] examined the effects of two energy restricted isocaloric diets of differing protein intakes in 19 lean (9.1-16.7% body fat), male, non-competitive body builders. One group consumed a protein intake of 0.8 g/kg and higher carbohydrates, while the other consumed 1.6 g/kg of protein with lower carbohydrates. The length of the intervention was only one week, but nonetheless nitrogen losses occurred only in the lower protein group and LBM decreased by a mean of 2.7 kg in the 0.8 g/kg protein group and by a mean of 1.4 kg in the 1.6 g/kg protein group. While the high protein group mitigated LBM losses compared to the low protein group, they were not eliminated.
A recent study by Mettler et al. [29] employed the same basic methodology as Walberg et al. [32]. However, one group consumed a protein intake of 1 g/kg, while the other consumed 2.3 g/kg. The high-protein group lost significantly less LBM (0.3 kg) over the course of the two week intervention compared to the low-protein group (1.6 kg). Unlike Walberg et al. [32] calorie balance between diets was maintained by reducing dietary fat as opposed to carbohydrate to allow for the increase in protein.
While it appears that the 2.3 g/kg protein intervention in Mettler et al. [29] was superior for maintaining LBM compared to 1.6 g/kg in Walberg et al. [32] a recent study by Pasiakos et al. [40] found a trend towards the opposite. In this study, a non-significant trend of greater LBM retention occurred when subjects consumed 1.6 g/kg of protein compared to 2.4 g/kg of protein. However, the participants were intentionally prescribed low volume, low intensity resistance training "to minimize the potential of an unaccustomed, anabolic stimulus influencing study outcome measures". Thus, the non-anabolic nature of the training may not have increased the participants’ protein requirements to the same degree as the participants in Mettler et al. [29] or to what would be expected among competitive bodybuilders.
Maestu et al. [6] did not observe a significant loss of LBM in a group of drug free bodybuilders consuming 2.5-2.6 g/kg of protein during the 11 weeks prior to competition. These results when considered alongside the works by Walberg et al. [32] and Mettler et al. [29] imply that the higher the protein intake, the lower the chance for LBM loss. However, it should be noted that this study did not include a low protein control and not all studies show a linear increase in LBM preservation with increases in protein [40]. Furthermore, two subjects did lose significant amounts of LBM (1.5 kg and 1.8 kg), and the authors noted that these specific bodybuilders were among the leanest of the subjects. These two subjects lost the majority of their LBM (approximately 1 kg) during the latter half of the intervention as their percentage of calories from protein increased from 28% to 32-33% by the end of the study. The group as a whole progressively decreased their calories by reducing all three macronutrients throughout the investigation. Thus, the two subjects uniquely increased their proportion of protein, possibly reducing fat and carbohydrate to the point of detriment [6]. That said it is also plausible that the lost LBM seen by these two subjects was necessary in order to achieve their low levels of body fat. It is unknown whether or not the lost LBM influenced their competitive outcome and it is possible that had the competitors not been as lean, they may have retained more LBM but also not have placed as well.
In a review by Phillips and Van Loon [28], it is suggested that a protein intake of 1.8-2.7 g/kg for athletes training in hypocaloric conditions may be optimal. While this is one of the only recommendations existing that targets athletes during caloric restriction, this recommendation is not given with consideration to bodybuilders performing concurrent endurance and resistance training at very low levels of body fat. However, the recently published systematic review by Helms et al. [33] on protein intakes in resistance-trained, lean athletes during caloric restriction suggests a range of 2.3-3.1 g/kg of LBM, which may be more appropriate for bodybuilding. Moreover, the authors suggest that the lower the body fat of the individual, the greater the imposed caloric deficit and when the primary goal is to retain LBM, the higher the protein intake (within the range of 2.3-3.1 g/kg of LBM) should be.
Mais bon, je devrai peut-être ne pas espérer que quelqu'un aille lire cet article puisque nous somme sur le forum d'un site web qui conseille de manger des œufs tout en citant des articles "scientifiques" financer par l'industrie des œufs américaines (
https://www.superphysique.org/articles/250 8. J Nutr. 2008 Feb;138(2):272-6. Dietary cholesterol from eggs increases plasma HDL cholesterol in overweight men consuming a carbohydrate-restricted diet. Mutungi G, Ratliff J, Puglisi M.
↵1 Author disclosures: G. Mutungi, J. Ratliff, M. Puglisi, M. Torres-Gonzalez, U. Vaishnav, J. O. Leite, E. Quann, and J. S. Volek, no conflicts of interest; and M. L. Fernandez, study funded by the Egg Nutrition Center
site web du egg nutrition center:
The Egg Nutrition Center is the research arm of the Amercian Egg Board. The American Egg Board (AEB) is the U.S. egg producer’s link to consumers in communicating the value of the incredible egg. AEB’s mission is to increase demand for egg and egg products on behalf of U.S. egg producers.
AEB is funded by a national legislative checkoff on all egg production from companies with greater than 75,000 layers. Its board is appointed by the U.S. Secretary of Agriculture and consists of 18 members and 18 alternates from all regions of the country all are egg producers nominated by certified state and regional organizations representing egg producers.