[Protein in the athlete's diet: rationale for intake levels at different training intensities to maintain lean body mass (a brief review)].

Nutrition in sports, as a branch of nutritional science, is a constantly developing field with a growing number of scientific researches and recommendations concerning the justification of the diet composition to ensure the requirements for macro- and micronutrients of the athlete's body at different stages of sports activity and energy value, as well as the use of special dietary supplements of various nature, including protein in forms of specialized dry mixes, drinks, etc. The aim of the research was to present the results of studies conducted abroad, presented in review publications and original articles, on the role of protein and the impact of its various levels of consumption on the maintenance of muscle mass as a criterion for the effectiveness of diets used, including in conditions of their reduced calorie content; on the safety of consuming significantly higher than recommended amounts of protein (>2.0 g/kg of body weight per day); about the relationship between protein dose and the possible increase in lean body mass. Material and methods. For the main source search, the PubMed Internet resource was used, and the websites of the Springer and Elsevier publishers were used to access the full text of the articles. Search depth 10 years. Results. This review presents the official position of the International Society of Sports Nutrition (ISSN) on the role of protein in training optimization, body composition change and improving the performance of athletes. Generalized data on the body's energy costs for the assimilation of nutrients, food thermogenesis and the importance of protein for maintaining resting energy expenditure are presented. Published results based on meta-analyses support the efficacy of higher protein intake in reducing body weight and fat mass while maintaining lean mass in an energy-deficient setting. The anabolic properties of protein under conditions of increased physical exertion will manifest themselves only with sufficient energy and protein supply. The proposed values and boundaries within which increased protein intake effectively affect body composition in the process of adaptation to strength training are given. It has been shown that an increase in protein intake above the average maximum values practically does not lead to an increase in lean body mass without the simultaneous introduction of additional resistance exercises that restores its growth. In accordance with the official position of the ISSN, the recommended protein intake corresponds to values from 1.4 to 2.0 g/kg of body weight per day for individuals performing various special sets of physical exercises. The use of high-protein diets (protein >2.0 g/kg/day) in highly qualified athletes who do not have kidney and liver diseases showed no changes in the biochemical parameters of blood and bone mineral density confirming its safety. Conclusion. Based on the analysis of scientific data, it can be stated that proteins make the main contribution to the thermogenesis of the body compared to other dietary macronutrients. The effect of protein intake on body composition, recovery and muscle building of an athlete has been proven. Athletes require higher amounts of protein to optimal increase of lean body mass under increased training loads and to maintain lean mass under an energy-deficient diet. If necessary, high-protein diets can be used in highly qualified athletes without kidney or liver diseases, but comprehensive researches in this direction should be continued.

[Amaranth grain proteins: prospects for use in specialized food products].

Amaranth is a widespread genus of predominantly annual herbaceous plants belonging to the Amaranthaceae family, which is one of the most widely used pseudocereals along with quinoa and buckwheat in nutrition. The aim of the research was to review and analyze the results of the studies on the characteristics of amaranth grain proteins, the effect of various food processing methods on their quality, and the prospects for using amaranth protein hydrolysates in therapeutic nutrition. Material and methods. For the main search for the literature, the PubMed bibliographic database was used, which covers about 75% of the world's medical publications. In addition, Scopus and Web of Science databases and non-commercial search engine Google Scholar were used. The depth of the search was 15 years. Results. The paper presents a brief review of modern approaches for obtaining amaranth protein isolates and concentrates, including the use of a complex of physicochemical methods: grinding, sifting, extraction at high pH values, defatting, ultrafiltration, centrifugation, isoelectric precipitation, and drying of the protein product. A comparative characteristic of amino acid content of protein fractions of pseudocereals is presented. Basically, leucine, isoleucine, and valine are limiting amino acids for the grain protein of various varieties of amaranth. When substantiating and developing modern effective food technologies for processing amaranth grain, the studies dedicated to the evaluation of their impact on the biological value of amaranth protein deserve special attention. Methods of grain fermentation, sprouting, steaming, malting, boiling can be used to increase the bioavailability and digestibility of its ingredients. The results of in vitro and in vivo studies indicate the presence of hypotensive, hypolipidemic and antioxidant activity of the amaranth protein and its hydrolysates what determines the prospects for their use as part of foods for special dietary uses and therapeutic nutrition. An analysis of the scientific publications presented in the review indicates an increase in demand for high-quality gluten-free products and an increase in the range of mass-consumption foods, such as bakery, pasta, flour confectionery, with pseudo-cereals in their composition, including amaranth. Conclusion. The high biological value and technological properties of amaranth protein concentrates/isolates determine the prospects for their use to create a wide range of specialized foods for various purposes.

[The efficiency of branched chain aminoacids (BCAA) in the nutrition of combat sport athletes].

Balanced nutrition of athletes involves the usage of both ordinary products and complexes of functional food ingredients that contribute to improving the performance of athletes, strengthening the immune system. One of the main components of specialized foods that are widely used in sports' nutrition and food supplements are branched chain aminoacids (BCAA): valine, leucine, isoleucine. The aim of the work was to study the effect of the BCAA intake on the parameters of body composition and the immune status of combat sport athletes during the training period. Material and methods. The object of the study was 20 athletes (masters of sports and candidates for masters of sports in combat sports: sambo, judo) at the age of 17-18 years. Athletes were distributed into 2 groups. Athletes of the main group (n=10) for 4 weeks in addition to the main diet were supplemented with BCAA at a dosage of 5 g per day. The athletes of the control group (n=10) received the main diet without BCAA inclusion. Examination of athletes of both groups was carried out at the beginning of the research and after 4 weeks of the observation period. The actual nutrition of athletes and daily energy consumption have been studied, body composition, the quantitative composition of subpopulations of peripheral blood lymphocytes, cytokine profile and hematological parameters have been determined. Results and discussion. As a result of a comprehensive survey of athletes, the positive effect of BCAA intake on the phase angle value (7.35±0.28 vs 6.41±0.32 at the beginning of the study, p<0.05) and muscle mass (25.1±0.8 vs 23.4±0.6 kg, p<0.10) has been demonstrated. In the control group these parameters did not change statistically significantly (7.05±0.25 vs 6.78±0.42 and 24.1±1.7 vs 23.8±1.5 kg). The athletes of the main group showed an increase in erythrocyte hemoglobin content (30.0±0.3 vs 29.0±0.2 pg, p<0.05). The relative content of basophilic leukocytes in athletes of the main group decreased by the end of the observation period - from 0.69±0.05 to 0.54±0.05% (p<0.05), that indicated an increase of immune resistance. The biomarker of the immunotropic effect of BCAA was the suppression of IL-4 production (1.6±0.1 to 1.3±0.1 pg/ml, p<0.05) synthesized by Th2 lymphocytes, with switching response to cellular immunity. Conclusion. The results of this study provide evidence of the effectiveness of BCAA usage in sports' nutrition for maintaining sport performance, immunity, and the adaptive potential of combat sport athletes.

[Immunomodulating effects of using L-carnitine and coenzyme Q10 in the nutrition of junior athletes].

Nowdays, much attention is paid to the study of disorders of immune regulation and methods of effective immune correction in athletes. In this regard, the use of specialized sport foods (SSF), containing nutrients with immunomodulatory properties, is of particular relevance in youth sports. The aim of the work is to study the immunomodulating activity of L-carnitine and coenzyme Q10 in junior athletes during the training period. Material and methods. The object of the study were 30 junior athletes (masters of sports and candidates for masters of sports in swimming) aged 14-18 years, including 9 girls and 21 boys. Athletes were divided into 3 groups of 10 people each. Athletes of the 1st and 2nd main groups received L-carnitine (600 mg per day) and coenzyme Q10 (60 mg/day), respectively, for 4 weeks in addition to the basic diet. The dosage of SSF used in the study was 200% of the adequate level of consumption and did not exceed the upper permissible level of consumption. Athletes of the 3rd group (control) received only basic diet without sports' nutrition. Examination of athletes of all groups was performed at the beginning and after 4 weeks of the observation period. Results and discussion. As a result of a comprehensive survey of junior athletes, the positive effect of L-carnitine intake on erythrocyte hemoglobin content (30.2±0.4 vs 28.3±0.3 pg at the beginning) was observed. The relative content of basophilic leukocytes in athletes of the main groups statistically significantly decreased by the end of the observation period: in the L-carnitine group, from 0.64±0.05 to 0.45±0.04%, in the coenzyme Q10 group, from 0.66±0.07 to 0.50±0.04%, which indicated an increase in the body's resistance to allergic reactions. Conclusion. The biomarkers of the immunotropic effect of L-carnitine and coenzyme Q10 are a decrease in the expression of the apoptotic marker CD95/Fas on peripheral blood lymphocytes and suppression of the production of pro-inflammatory cytokines synthesized by Th1-lymphocytes with switching the response to humoral immunity. An evidence base for the effectiveness of the use of L-carnitine and coenzyme Q10 in sports nutrition for restoring immune dysfunction and adaptive potential of junior athletes has been provided.

[Complex of zinc with enzymatic hydrolysate of pigspleen protein - in vivo investigation].

Experimental sample of complex zinc with enzymatic hydrolysate of pigspleen protein (Zn-EHPS) was produced in laboratory with ultra- and nanofiltration technologies; its composition was analyzed; male rats Wister (initial body weight 132±2,4 g) were under observation in vivo: rats weregiven zinc-deficient ration (ZDR) "Zinc Deficient Diet, Egg White Base", containing not more than 1,3 mg zinc/kg, and water ad libitum during 18 days. Animals were divided into 3 groups (10 in each): group I was given ZDR and distilled water; group 2 - ZDR and water zinc sulphate solution (ZnSO4) with zinc concentration of 16,3 mcg/ml; group 3 - ZDR and water Zn-EHPS solution with zinc concentration of 16,3 mcg/ml. All rats were daily observed with registration of water consumption. Unconditioned reflex (photophobia) or crossing time from light to darkness on special system before the beginning of experiment was tested out. An increase of body weight (ΔW) during the experiment, unconditioned reflex stability and training to conditioned passive avoidance reflex (CPAR) after paw painful electric stimulation were studied. On 18 day in 16 hours after paw painful electric stimulation alkaline phosphatase activity (AP) and corticosterone concentration in rat blood serum were examined. Insignificant changes in distribution of peptide fractions according its molecular mass and practical complete remove of free metal ions from final product were observed when Zn-EHPS-technology were used. During experiment in all groups correspondently ΔW was 23,87 and 82% (p<0,05); AP activity - 1,70±0,06; 3,10±0,25; 4,19± 0,26 mcmol/l/s (p<0,01); corticosterone concentration - 20,7±7,2; 21,5±6,3; 22,1±16,5 ng/ml (p>0,1) were observed. Significant (p<0,05) worse change of unconditioned reflex (photophobia) in group 1 (ZDR) in comparison with group 2 and group 3 (latent period - LP, s: 50,9±12,0; 18,2±16,0; 16,0±4,2) as well as to initial test (LP, s - 16,8±8,0) was found on the 14th day of the experiment. According to LP-test CPAR in all groups in 24 and in 96 hours after paw painful electric stimulation was found to be maintained. Data obtained let to suggest high bioavailability of new zinc organic form - Zn-EHPS and its usage possibility in fortification of special foods.

[Investigation of actual nutrition and some factors of physical status in rugby players].

Physical status and nutrition and energy value of factual diets of 18 rugby players (15-30 years old) assessed during current medical observation were analyzed. Anthropometric data (height, body mass--BM, waist circumference/ hip circumference index, body mass index--BMI), body composition data and resting metabolic rate by bioimpedance method (analyzer ABC-01 "Medass") were determined. These indices were found to be normal except more high level of BMI due to high levels of lean and skeletal muscle mass, but not a result of obesity. Estimation of factual nutrition based on 1-day feeding (nutrition-screening questionnaire method) has demonstrate that it was not optimal both for energy and nutrition value for this group of physical activity. Energy value ranged from 1889 kcal to 3175 kcal (22.5-35.1 kcal/kg BM/day) with lower carbohydrate intake (46.9%) and higher fat intake (35.8%) were found. Nutrition value ranges: protein--67-144 g (0.71-1.38 kcal/kg BM/day), fat--75-140 g (0.88-1.51 kcal/kg BM/day), carbohydrate--173-420 g (2.17-4.66 kcal/kg BM/day) were observed. The findings suggest the need to pay more attention to in-depth study of dietary intake of athletes to maintain health and to create optimal conditions for a professional sports activities.

[Medical-biological approach to development of feeding ration for sportswomen--members of Russia weight lifting team].

Physical status of 12 sportswomen - member of Russia weight lifting team during training period was analiysed. Anthropometric, bioimpedance methods with analyzer ABC-01 "Medass" in observation [body weight Index (index Ketle-2), waist circle/hip circle index] and body compositions were used (adipose, bone and muscle tissues masse). Data obtained when bioimpedance method was used indicated: normal body weight and relative adipose mass to body weight - in 92%, surplus - in 8% of cases; body weight Index and normal level of adipose mass - in 75%, surplus - in 25%; active cellular mass and bone mass and general body liquid were found to be normal. 14-day feeding ration for sportswomen were analysed and 3 times per day food intakes was found to be not optimal. Data obtained let to recommend set of daily food products to compose optimal ration for present sportswomen group when energetic value of 4500 kKal and high nutritional value would be provided.

[Enriched and functional foodstuffs: similarities and differences].

A comparison of fortified and functional foods on such parameters as destination, food group, the principles of enrichment with vitamins and/or macro- and micronutrients, doses and forms of vitamins and minerals, hygienic regulations of micronutrients usage and content in the final product, regulatory and technical documentation, duration of application, effectiveness, labeling, information for consumers has been carried out. Insufficiency and the need to improve the regulatory framework for functional foods are noted.

[Analyses of special foods for sportsmen (received for 2007-2010 years)].

Review of about special foods for sportsmen (SFS) when 80% of which were imported and to be received for 2007-2010 years is presented. Discrepancy with demands of Russian legislation of some SFS (about 30%) is noted. Sufficiently wide spectrum of proposed products and tendency to progressive complication of SFS composition are observed. Data obtained let to suggest that possibility to have more expected effectiveness when such products are used can be one of explanation of that tendency.

[Principles of optimal nutrition of sportsmen in various kinds of sport].

Basic principles of optimal nutrition of sportsmen in various kinds of sport are formulated. Their diet must be well-balanced in terms of all nutrients and contain essential vitamins and minerals. There is outlined an indispensable content of the basic nutrients in sportsmen's daily diet: proteins, fats, carbohydrates, as well as vitamins and minerals.

[Effect of carrageenan on indices of protein biological value and assimilability].

Influence of different levels of dietary carrageenan (0.2; 0.6, 2% with 18% casein) after 4 weeks in rats on coefficients of biological value (PER, NPR, NPUtr u BVtr) and digestibility (Dtr) of protein, microflore in cecum and morphometric data in distal part of small intestine were studied. There were found adverse changes of coefficients of biological value (NPUtr, BVtr) and digestibility (Dtr) after 2% dose of carrageenan. Chandes in microflore of cecum and worse of morphometric data in small intestine were observed.

[Express method to estimate alpha-amilase activity in specialized food products and dietary supplements].

More simple method to estimate of alpha-amilase activity in special foods and food supplements is proposed.

[Comparative evaluation of zinc organic and inorganic form bioavailability in vivo].

Bioavailability of zinc complex with enzymatic hydrolysate of milk protein (EHMP) was studied in Wistar rats. Body mass, zinc content in os femoris and serum alkaline phosphatase activity were similar in rats receiving Zn-EHMP and zinc sulphate and were significantly higher than in animals fed with basal semi synthetic zinc-deficient diet. Apparent absorption of both Zn sources in rat's intestine was high (more than 70%) probably due to absence of plant dietary fiber in applied diet. Zinc organic form use in fortification of food is discussed.

[Microalgae Spirulina in human nutrition]. / Mikrovodorosl' Spirulina v pitanii cheloveka.

Spirulina microalgae (Spirulina platensis, Spirulina maxima, Spirulina fusiformis) is considered as a valuable additional food source of some macro- and micronutrients including high quality protein, iron, gamma-linolenic fatty acid, carotenoids, vitamins B1 and B2. In spite of Spirulina chemical composition varies widely when grown in open reservoirs its efficiency as an additional remedy in treatment and prophylaxis of different diseases is proved in a variety of experimental and clinical trials. During Spirulina cultivation in open reservoirs and especially in closed photobioreactors its biomass may be additionally enriched with some trace elements such as iron, iodine, selenium, zinc, copper, manganese and chromium in high bioavailable form. Said biomass is considered as a constituent of new bioactive food supplements.

[Role of soybean proteins in human nutrition (review)]. / Rol' soevykh belkov v pitanii cheloveka (obzor).

Review. The analysis of a protein nutrition of Russia's population during last five years and ways of its rationalization are presented. The scientific background for prosperity of using of soy bean proteins, products of their processing and existing of products and half-finished products received from soy is given. Experimental data on biological value and bioavailability of soy bean proteins and results of clinical evaluation of curative and preventive effects of these various soy products are discussed.

[Research on xenobiotic metabolism for assessing the quality of protein-containing products from plant raw material produced through biotechnology methods]. / Issledovanie metabolizma ksenobiotikov dlia otsenki kachestva beloksoderzhashchikh produktov iz rastitel'nogo syr'ia, poluchaemykh metodami biotekhnologii.

Activity of microsomal hydroxylation and conjugation enzymes was studied in the liver of rats that received food concentrate of protein from sunflower groats (SPC) produced in the USSR, and soya protein isolate (SPI) produced by Ralston Purina, USA. SPC consumption during 3 months was attended by elevation of cytochrome-450 content, and activity of microsomal hydroxylation and uridinephosphate-glucuroniltransferase (UDP-GT) in hepatic microsomes, that may evidence the presence in SPC of chemical compounds of natural origin, or chemical modification of the own amino-acid products. SPI did not influence activity of microsomal hydroxylation enzymes, but it raised UDP-GT activity. Both protein products produced no effect on activity of enzymes associated with glutathione metabolism--glutathione-S-transferase and glutathione-reductase in hepatic cytosol. However, SPC and SPI induced a manifold rise in glutathione-peroxidase activity in cytosol of the liver and blood that indicates the presence of the trace element selenium in the products studied.

[The biological value of the proteins of dairy products with varying contents of lactose]. / Biologicheskaia tsennost' belkov molochnykh produktov s razlichnym soderzhaniem laktozy.

In experiments on growing Wistar male rats biological value of proteins was estimated in 5 milk products containing proteins: "Detolact", "Humana O", "Novolact MM", lactalbumin and "Dialact" containing from 17 to 58% of lactose. The final level of lactose in the ration (7% of protein by mass) varied from 4.4 to 30.6%. The parameters of protein biological value in the tested products did not significantly differ from those of the control protein (casein) that has proved the validity of using rats for investigation of biological value of proteins in the rations containing up to 30% of lactose.

[The action of different food factors on the lipid peroxidation processes in the liver microsomes of rats]. / Vozdeistvie razlichnykh pishchevykh faktorov na protsessy perekisnogo okisleniia lipidov v mikrosomakh pecheni krys.

Three series of experiments were conducted to study the effects of varying food factors on lipid peroxidation (LPO) activity in rat liver microsomes. The food rations contained heat-treated sunflower oil, soybean protein isolate, krill protein concentrate. A long-term intake of heat-treated oxidation products was attended by significant activation of LPO in the enzymatic system, by elevation of cytochrome P-450 level, by increased activity of ethylmorphine N-demethylase and aniline n-hydroxylation. The period of half-inactivation of cytochrome P-450 was significantly shortened in NADPH-dependent LPO. The rate of NADPH-dependent LPO was not significantly different in the animals given equal amounts of soybean protein isolate or casein (control). Activation of NADPH-dependent LPO and induction of cytochrome P-450 were recorded in liver microsomes of the animals given krill protein. The high concentration of cytochrome P-450 (in the homogenate and microsomes) correlated with the acceleration of hydroxylation of standard substrates ethylmorphine and aniline.

[Effect of long-term consumption of various krill products on lysosomal proteinase activity in rats]. / Vliianie dlitel'nogo potrebleniia razlichnykh krilevykh produktov na aktivnost' proteinaz lizosom u krys.

Total and nonsedimentable cathepsin A, B, C and D activity was studied in the liver and kidneys, as well as in the blood serum of rats fed with rations containing protein isolate from krill (100 and 50%) and krill flesh (100%) during .6 and 12 months. Selective activation of cathepsins A dn D in the liver, intensified nonsedimentable activity of all lysosomal proteinases studied, most manifest at the initial stages of the experiment (4 months), and a sharp (0.5-3.5-fold) rise of these enzymes' activity in the blood serum were recorded in rats when the krill isolate served the only source of protein (100%) in their ration.