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Protein requirements and supplementation in strength sports
Abstract and Figures
Daily requirements for protein are set by the amount of amino acids that is irreversibly lost in a given day. Different agencies have set requirement levels for daily protein intakes for the general population; however, the question of whether strength-trained athletes require more protein than the general population is one that is difficult to answer. At a cellular level, an increased requirement for protein in strength-trained athletes might arise due to the extra protein required to support muscle protein accretion through elevated protein synthesis. Alternatively, an increased requirement for protein may come about in this group of athletes due to increased catabolic loss of amino acids associated with strength-training activities. A review of studies that have examined the protein requirements of strength-trained athletes, using nitrogen balance methodology, has shown a modest increase in requirements in this group. At the same time, several studies have shown that strength training, consistent with the anabolic stimulus for protein synthesis it provides, actually increases the efficiency of use of protein, which reduces dietary protein requirements. Various studies have shown that strength-trained athletes habitually consume protein intakes higher than required. A positive energy balance is required for anabolism, so a requirement for "extra" protein over and above normal values also appears not to be a critical issue for competitive athletes because most would have to be in positive energy balance to compete effectively. At present there is no evidence to suggest that supplements are required for optimal muscle growth or strength gain. Strength-trained athletes should consume protein consistent with general population guidelines, or 12% to 15% of energy from protein.
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... Improving skeletal muscle health increases physical function [12], insulin sensitivity [13], and lowers the risks of cardiovascular disease and hypertension [11,14], increases the chances of osteoporosis and mortality [15]. Resistance exercise increases the demand for protein to sustain increased protein synthesis for hypertrophy and to compensate for muscle protein breakdown caused by exercise [16]. While the RDA of 0.8g protein/kg body weight/day fulfills most people's nitrogen balance demands [16] while1.4-2.0g/kg ...
... Resistance exercise increases the demand for protein to sustain increased protein synthesis for hypertrophy and to compensate for muscle protein breakdown caused by exercise [16]. While the RDA of 0.8g protein/kg body weight/day fulfills most people's nitrogen balance demands [16] while1.4-2.0g/kg body weight/day is recommended by experts for those persons who perform extensive exercise [17]. ...
Once the consumer acknowledges that foods containing dietary cholesterol are not a risk factor for
cardiovascular disease. The eggs contain dietary cholesterol and must be valued for their other nutritional
components. Egg protein is one of the components in eggs that demands special attention. Egg protein has
a high biological value and provides essential amino acids. Egg protein has been shown to be beneficial to
musculoskeletal health. Egg protein may also suppress appetite, resulting in a reduction in calorie intake
which leads to weight loss.
... Early literature maintained that athletes were recommended to consume protein at levels consistent with those of the general population, which equates to roughly 12-15% of energy from protein [30]; however, more recent research suggests that athletes' protein intake requirements exceed the general population's [11]. Recent indicator amino acid oxidation studies by Bandegan et al. demonstrate athletes' protein requirements are around 1.9 g/kg of bodyweight [31,32]; thus, plant-based diets risk falling short of optimal levels Content courtesy of Springer Nature, terms of use apply. ...
... Plant-based diets are on average less proteinaceous than non-plant-based diets, however, both diet styles can attain appropriate daily protein intake levels [28,30], suggesting that adequate protein ingestion is not necessarily dependent solely on its source. Micronutrient intake, however, is dependent on source, as some micronutrients are derived strictly from animal-based products, which places plantbased dieters at higher risk of micronutrient deficiency if unaware [12,19,36,37]. ...
Purpose
Plant-based diets have become increasingly popular in Western culture. Although studies have examined physiologic health improvements of plant-based diets, there is little data on plant-based diets as it relates to sports performance.
Methods
Clinical review of systematic reviews, randomized trials, prospective and retrospective cohort studies available in English on PubMed and Google Scholar databases utilizing combinations of the search terms “athlete, sport, nutrition, diet, vegan, vegetarian, strength, endurance, health, performance, and exercise.”
Results
There are no significant differences in athletic performance in participants maintaining plant-based diets compared to those consuming omnivorous diets specifically related to strength, power, and endurance. Plant-based diets are at higher risk of predisposing individuals to certain micronutrient deficiencies, reduced protein intake, and lower serum creatine and sex testosterone levels, though supplementation may effectively replace the lacking components. Non-plant-based diets are associated with a higher risk of obesity, type II diabetes mellitus, certain malignancies, and cardiovascular disease, though several studies demonstrate that a particular meat- and fish-filled diet may reduce body weight, blood pressure, fat composition, and all-cause mortality.
Conclusion
Though plant-based and mixed omnivorous eaters may vary in their macronutrient and micronutrient intake, disease propensities, and oxygen consumption during exertion, a plant-based diet does not translate into a significantly different physical performance compared to a non-plant-based diet across measures of strength, power, and aerobic/anaerobic performance. For athletes, trainers, nutritionists and dieticians, and physicians, the most important recommendation is to maintain a nutritionally sufficient diet that provides the appropriate levels of vital nutrients and vitamins.
... It brings a new, highly interactive and expressive interactive experience [1][2][3][4]. The sport of tai chi is a representative sport in Chinese traditional sports and occupies a very important position in Chinese traditional sports [5][6][7][8]. The Taiji culture in Chinese martial arts is a culture of body bonding, a culture of health, and a culture that differs from Western fitness culture [9][10][11][12]. ...
As a pearl in the treasury of Chinese traditional culture, taijiquan is the crystallization of the wisdom of the entire Chinese nation and contains a rich cultural connotation. Its role and influence in the field of cross-cultural studies is increasing as China’s comprehensive power grows. This paper aims to promote Chinese civilization and the essence of Taiji culture to the world. Through the artificial intelligence algorithm calculations, the path of international promotion of taijiquan is inferred. By using the implementation of taijiquan teaching programs in groups as a medium to promote the culture of taijiquan from groups to the world in all aspects, thus promoting cultural exchanges around the world and thus promoting the deeper development of Chinese martial arts culture. The results of the experiment showed that students, for example, were very curious about using VR technology to learn taijiquan at 27%. Most of the students were looking forward to learning taijiquan using VR technology, indicating that VR technology in the context of artificial intelligence is important for the public to understand taijiquan and to promote taijiquan internationally.
... Гипертрофия мышечных волокон также нуждается в положительном азотистом балансе -синтез мышечного белка обязательно должен превышать его распад. Различные исследования демонстрируют, что силовые тренировки стимулируют синтез мышечного белка, как у тренированных, так и нетренированных людей [3]. ...
Polyaniline (PANi) hydrogels that combine advantages of hydrogels and conductive PANi have recently emerged in areas of wearable devices and personal healthcare. Nevertheless, their mechanical performance often gradually degrades after being used for a period, caused by destruction of the inner structures when external forces are applied. Inspired by biological structures with persistent durability, we develop here a phytic acid-assisted PANi/poly(vinyl alcohol) (PVA) hydrogel that shows self-reinforcing features. As a natural product holding plenty of phosphate groups, phytic acid (PA) plays two crucial roles when preparing this hydrogel: (1) aniline is salinized by PA in aqueous solution to promote in situ polymerization, making the resulting PANi conductive; (2) PA/PANi particles form hydrogen bonds with PVA, acting as stress concentration points to induce structure orientation. The optimal PVA/PA/PANi hydrogel displays dark green color with a uniform distribution of PA/PANi particles. After experiencing repetitive 4 × 100 stretching at a strain of 10%, the hydrogel exhibits an enhanced fracture strength (20.35 MPa), Young's modulus (22.66 MPa), and toughness (36.24 MJ·m-3) compared with the original hydrogel. This self-reinforcing feature is mainly attributed to the formation of anisotropic structures fixed by hydrogen bonds between PA/PANi particles and PVA chains upon repetitive external forces. Moreover, anisotropic structures can be disassembled by swelling the post-stretched hydrogel in water, and the swollen hydrogel shows similar self-reinforcing behaviors. The good mechanical durability and reusable characteristics make the PVA/PA/PANi hydrogel a reliable strain sensor. This work provides a structural growing-reviving approach for conductive hydrogels with persistent durability.
El objetivo consistió en determinar el grado de incidencia que tiene el consumo de huevo en la masa muscular en la población masculina del gimnasio en Lima Metropolitana. La metodología fue cuantitativa y el desarrollo fue comparando a través de muestras aleatorias usando variables tipo: edad, índice de masa corporal, tiempo de entrenamiento, cantidad de huevos de consumo al día, forma de consumo, medida de masa muscular, presión arterial, grado de diabetes. La base de datos registró una población masculina de 13,909 clientes y 504 entrenadores. Se calculó el tamaño de la muestra a través del método de poblaciones finitas, llegando a ser entrevistados 30 para clientes y 29 instructores. Entre los resultados, que la población de entrenadores aumenta 23% la masa muscular por el consumo de huevo, sin embargo, no se descarta que estos consuman productos que le ayuden a sintetizar con mayor velocidad las proteínas, como son los anabólicos.
Background:
The indicator amino acid oxidation (IAAO) method has been accepted as an approach to evaluate habitual protein requirements under free-living conditions.
Objective:
This scoping review reports on literature that evaluated protein requirements in humans using the IAAO methods.
Methods:
Three databases (PubMed/Medline, Web of Science, and ProQuest) were systematically searched to identify studies that evaluated protein requirements using the IAAO method published in English until June 5, 2023. We evaluated the study quality using previously developed criteria. We extracted the characteristics of the study design and the results of protein requirements. Two reviewers conducted both reviews and quality assessments independently; any differences among them were resolved by consensus or agreement of all team members.
Results:
We extracted 16 articles targeting children, young adults (including pregnant women, resistance training athletes, endurance training athletes, and team sports), and older adults. For quality assessment, 14 studies were evaluated "strong", but the remaining two were "moderate". These studies were conducted in only three countries and not for all sexes or life stages. The range of the estimated average protein requirements of each life stage were 1.3 g/kg body weight/day for children, 0.87 to 2.1 (0.87 - 0.93 for general young adults, 1.22 - 1.52 for pregnant women, 1.49 - 2.0 for resistance-trained athletes, 1.65 - 2.1 for endurance athletes and 1.2 - 1.41 for team sports athletes) g/kg body weight/day for young adults, and 0.85 to 0.96 g/kg body weight/day for older adults.
Conclusions:
Protein requirements in 14 studies were higher than the current reference for each sex, life stage and physical activity that are related to protein requirement. In the future, protein requirements of various population including sex, life stage could be assessed using the IAAO methods worldwide.
Resumo Introdução: A dieta vegetariana, alimentação baseada em plantas, se mostra eficiente no ganho de massa muscular, uma vez que contém alimentos de boa qualidade, resultando em benefícios para os praticantes de exercício físico de força. Objetivo: Realizar revisão integrativa de literatura sobre a influência da dieta vegetariana aplicada a praticantes de atividade física com o intuito de aumento de massa muscular. Metodologia: Para a análise do estudo, foram realizadas coletas de artigos referentes à aplicação de dietas vegetarianas em praticantes de atividade física intensa e/ou de força com o intuito de ganho de massa muscular, para que se tenha grande aporte de informações sobre o tema tratado. Resultados: A alimentação vegetariana pode contribuir para hipertrofia muscular e ganho de massa magra tanto ou mais que a dieta onívora desde que seja bem planejada e balanceada. O teor de massa magra e a força podem ser superiores no grupo de onívoros quando comparados aos indivíduos vegetarianos. Conclusão: A dieta vegetariana demonstra-se positiva para o ganho de massa muscular através de exercícios de força, desde que haja uma adequação de proteínas e aminoácidos na dieta. Palavras-Chave: HIPERTROFIA; DIETA VEGETARIANA; EXERCÍCIO. Abstract Introduction: The vegetarian diet, a plant-based diet, is efficient in gaining muscle mass, as it contains good quality foods, resulting in benefits for strength training practitioners. Objective: Carry out an integrative literature review on the influence of the vegetarian diet applied to physical activity practitioners in order to increase muscle mass gain. Methodology: For the study analysis, articles referring to the application of vegetarian diets in practitioners of intense physical activity and/or strength training in order to gain muscle mass were collected, so that there is a large amount of information on the subject treated. Results: Vegetarian food can contribute to muscle hypertrophy and lean mass gain as much or more than the omnivorous diet, provided it is well-planned and balanced. Lean mass content and strength may be higher in the omnivore group when compared to vegetarian individuals. Conclusion: The vegetarian diet is positive for muscle mass gain through strength training exercises, as long as there is an adequacy of proteins and amino acids in the diet.
Rationale:
Heavy water can be used as a tracer for the evaluation of protein turnover. By adding heavy water (D2 O) to the precursor pool, non-essential amino acids, including alanine, can be isotopically labeled in vivo. Protein turnover can then be quantified by measuring the hydrogen isotope ratio of protein-bound alanine.
Methods:
In this study, we constructed a novel method to apply deuterium labeling of alanine to the evaluation of protein turnover using elemental analysis coupled to isotope ratio mass spectrometry (EA-IRMS). We established a preparative HPLC method to isolate alanine from protein hydrolysates. EA-IRMS was then used to determine the hydrogen isotope ratio of alanine isolated from hydrolysates of protein from mouse myoblast C2C12 cells that had been treated with D2 O over the course of 72 hours.
Results:
In cells treated with 4% D2 O, the deuterium enrichment of alanine increased to approximately 0.9% over time, while that of cells treated with 0.017% D2 O increased to approximately 0.006%. The rate of protein synthesis calculated by fitting the increase of deuterium excess to rise-to-plateau kinetics was similar regardless of the concentration of D2 O. When C2C12 cells treated with insulin and rapamycin were analyzed 24 hours after the addition of 0.017% D2 O, protein turnover was found to be accelerated by insulin, but this effect was offset by co-treatment with rapamycin.
Conclusion:
The derivative-free measurement of the hydrogen isotope ratio of protein-bound alanine using EA-IRMS can be applied to the evaluation of protein turnover. The proposed method is a accessible option for many laboratories to perform highly sensitive IRMS-based evaluations of protein metabolic turnover.
Relato de Experiência: o projeto de intervenção foi realizado em 3 momentos. O primeiro momento foi feito a coleta de amostras microbiológicas da mão dominante do aluno e eventualmente incubadas em placas de petri. No segundo momento foi demonstrado as placas de petri identificadas de cada aluno como forma de visualização da contaminação das mãos e no mesmo dia foi ministrado uma palestra explicando a importância da higienização das mãos. No 3 momento e último foi aplicado um questionário como forma de avaliação do projeto realizado. Considerações Finais: Por meio do projeto foi possível perceber que o mesmo teve um resultado positivo em relação a conscientização dos alunos sobre a importância de práticas higiênicas nas mãos.
McCall, G. E., W. C. Byrnes, A. Dickinson, P. M. Pattany, and S. J. Fleck. Muscle fiber hypertrophy, hyperplasia, and capillary density in college men after resistance training. J. Appl. Physiol. 81(5): 2004–2012, 1996.—Twelve male subjects with recreational resistance training backgrounds completed 12 wk of intensified resistance training (3 sessions/wk; 8 exercises/session; 3 sets/exercise; 10 repetitions maximum/set). All major muscle groups were trained, with four exercises emphasizing the forearm flexors. After training, strength (1-repetition maximum preacher curl) increased by 25% ( P < 0.05). Magnetic resonance imaging scans revealed an increase in the biceps brachii muscle cross-sectional area (CSA) (from 11.8 ± 2.7 to 13.3 ± 2.6 cm ² ; n = 8; P < 0.05). Muscle biopsies of the biceps brachii revealed increases ( P < 0.05) in fiber areas for type I (from 4,196 ± 859 to 4,617 ± 1,116 μm ² ; n = 11) and II fibers (from 6,378 ± 1,552 to 7,474 ± 2,017 μm ² ; n = 11). Fiber number estimated from the above measurements did not change after training (293.2 ± 61.5 × 10 ³ pretraining; 297.5 ± 69.5 × 10 ³ posttraining; n = 8). However, the magnitude of muscle fiber hypertrophy may influence this response because those subjects with less relative muscle fiber hypertrophy, but similar increases in muscle CSA, showed evidence of an increase in fiber number. Capillaries per fiber increased significantly ( P < 0.05) for both type I (from 4.9 ± 0.6 to 5.5 ± 0.7; n = 10) and II fibers (from 5.1 ± 0.8 to 6.2 ± 0.7; n = 10). No changes occurred in capillaries per fiber area or muscle area. In conclusion, resistance training resulted in hypertrophy of the total muscle CSA and fiber areas with no change in estimated fiber number, whereas capillary changes were proportional to muscle fiber growth.
Reliable standards relating to physiological requirements are needed in order to estimate nutritional needs of populations. Probably the most important standards in terms of national and international planning are those for energy and protein, because the need for these nutrients determines to a major extent the amount, composition and cost of food supplies. These standards, reflecting physiological requirements, are properly used to set nutritional targets and to assess intakes of populations. Comparison of an array of intake and requirements values, for households in communities or for groups of individuals of a given age sex category, can indicate nutritional risk: that is, the probability of deficiency in the populations examined, even though deficient individuals or households cannot be identified from this information alone. Requirements figures are often used to estimate the food energy and protein needs of communities and nations. This is commonly done to compare availability of food supplies with population needs in deriving food balance sheets. All that these balances can show is whether or not a nation has enough food potentially to meet its needs, not who or how many may be malnourished, as this depends upon how equitably the foods are distributed. (Journal received 31 Jan. 1977)
Muscle mass declines with aging. Amino acids alone stimulate muscle protein synthesis in the elderly. However, mixed nutritional supplementation failed to improve muscle mass. We hypothesized that the failure of nutritional supplements is due to altered responsiveness of muscle protein anabolism to increased amino acid availability associated with endogenous hyperinsulinemia. We measured muscle protein synthesis and breakdown, and amino acid transport in healthy young (30 +/- 3 yr) and elderly (72 +/- 1 yr) volunteers in the basal postabsorptive state and during the administration of an amino acid-glucose mixture, using L-[ring-(2)H(5)]phenylalanine infusion, femoral artery and vein catheterization, and muscle biopsies. Basal muscle amino acid turnover was similar in young and elderly subjects. The mixture increased phenylalanine leg delivery and transport into the muscle in both groups. Phenylalanine net balance increased in both groups (young, -27 +/- 8 to 64 +/- 17; elderly, -16 +/- 4 to 29 +/- 7 nmol/(min.100 mL); P: < 0.0001, basal vs. mixture), but the increase was significantly blunted in the elderly (P: = 0.030 vs. young). Muscle protein synthesis increased in the young, but remained unchanged in the elderly [young, 61 +/- 17 to 133 +/- 30 (P: = 0. 005); elderly, 62 +/- 9 to 70 +/- 14 nmol/(min.100 mL) (P: = NS)]. In both groups, protein breakdown decreased (P: = 0.012) and leg glucose uptake increased (P: = 0.0258) with the mixture. We conclude that the response of muscle protein anabolism to hyperaminoacidemia with endogenous hyperinsulinemia is impaired in healthy elderly due to the unresponsiveness of protein synthesis.
J Physiol 2001 August 15: 535(1): 301–11(1) Age-associated loss of skeletal muscle mass and strength can partly be counteracted by resistance training, causing a net synthesis of muscular proteins. Protein synthesis is influenced synergistically by post-exercise amino acid supplementation, but the importance of the timing of protein intake remains unresolved. (2) The study investigated the importance of immediate (P0) or delayed (P2) intake of an oral protein supplement upon muscle hypertrophy and strength over a period of resistance training in elderly males. (3) Thirteen men (age 74 ± 1 years; body mass index (BMI), 25 ± 1 kg m- 2 (means ± SEM)) completed a 12-week resistance training program (three times per week) receiving oral protein in liquid form (10 g protein, 7 g carbohydrate, 3 g fat) immediately after (P0) or 2 h after (P2) each training session. Muscle hypertrophy was evaluated by magnetic resonance imaging (MRI) and from muscle biopsies and muscle strength was determined using dynamic and isokinetic strength measurements. Body composition was determined from dual-energy X-ray absorptiometry (DEXA) and food records were obtained over 4 days. The plasma insulin response to protein supplementation was also determined. (4) In response to training, the cross-sectional area of m. quadriceps femoris (54.6 ± 0.5–58.3 ± 0.5 cm2) and mean fiber area (4047 ± 320–5019 ± 615 μ m2) increased in the P0 group, whereas no significant increase was observed in P2. For P0 both dynamic and isokinetic strength increased, by 46 and 15%, respectively (P P
Thesis (M.S.)--Boston University, 1995. Includes bibliographical references.
A diet supplying 0.5 or 1 g egg and milk protein/kg per day and adequate energy for maintenance of body weight was given to seven healthy men aged 18 to 21. After 2 weeks for adaptation to the diet they participated in 75 min of daily isometric exercises for 4 to 6 weeks. Two men on each protein intake continued to exercise for 4 to 5 additional weeks after undergoing changes in their daily protein intake from 0.5 to 1 g/kg or vice versa. A progressive decrease in total body potassium became significant by the fourth week of exercises in all men who began on the 0.5 g protein diet. Two men on that diet who remained as nonexercising controls lost no body K. These findings indicated that 0.5 g of egg and milk protein/kg per day was insufficient for men performing isometric exercises without prior training, whereas 1 g/kg per day appeared to be adequate. Two other nonexercising men on the 0.5 g diet who lost weight showed a marked negative nitrogen balance and loss of total body potassium which improved after their dietary energy intake increased. The changes in nitrogen balance and body weight observed in this investigation support the concept that protein requirements vary with energy intakes. Conversely, they suggest that energy requirements are influenced by the level of protein intake.
The quantitative effect on protein utilization of an isoenergetic exchange of dietary fat for carbohydrate was studied in 10 healthy young men. Milk protein (0.57 g/kg body weight per day, a safe level of protein intake as recommended by FAO/WHO) was given for two 21-day experimental periods with two ratios of carbohydrate to fat calories: diet A, a ratio supplying an equal proportion of energy from carbohydrate and from fat, generally representative of the usual Western diet, and diet B, a ratio supplying twice as much energy from carbohydrate as from fat, chosen in view of recommendations to reduce the amount of fat in the diet. Total calorie intake for each subject was constant over the two experimental periods. During each period, five subjects showed a consistent gain and five a loss of body weight. Urinary creatinine excretion was essentially unchanged. Nitrogen (N) balance and dietary protein utilization were significantly (P < 0.05) improved on diet B. The protein-sparing effect was greatest in those subjects who were on marginal energy and protein intakes and who were losing weight. The additional carbohydrate in diet B resulted in significant reductions in fasting serum urea N (P < 0.001), total urinary N (P < 0.01), and urinary urea N (P < 0.001); fasting plasma insulin values were unchanged. Whether or not the longer-term effects of the change in dietary carbohydrate:fat ratio on N metabolism are mediated solely by the action of insulin remains to be determined. Am. J. Clin. Nutr. 32: 22 17-2226, 1979.
Nine healthy subjects were studied under control conditions and following 5 mo of heavy resistance training and 5 wk of immobilization in elbow casts. Needle biopsies were taken from triceps brachii and analyzed for adenosine triphosphate (ATP), adenosine diphosphate (ADP), creatine (C), creatine phosphate (CP, and glycogen concentrations. Training resulted in an 11% increase in arm circumference and a 28% increase in maximal elbow extension strength. Immobilization resulted in decreases in arm circumference and elbow extension strength of 5% and 35%, respectively. Training also resulted in significant increases in resting concentrations of muscle creatine (by 39%), CP (by 22%), ATP (by 18%), and glycogen (by 66%). Conversely, immobilization significantly reduced CP concentration by 25% and glycogen concentration by 40%. It was concluded that heavy-resistance training results in increases in muscle energy reserves which may be reversed by a period of immobilization-induced disuse.