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1.
Nutrients ; 13(12)2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34959912

RESUMO

l-Carnitine (l-C) and any of its forms (glycine-propionyl l-Carnitine (GPL-C) or l-Carnitine l-tartrate (l-CLT)) has been frequently recommended as a supplement to improve sports performance due to, among others, its role in fat metabolism and in maintaining the mitochondrial acetyl-CoA/CoA ratio. The main aim of the present systematic review was to determine the effects of oral l-C supplementation on moderate- (50-79% V˙O2 max) and high-intensity (≥80% V˙O2 max) exercise performance and to show the effective doses and ideal timing of its intake. A structured search was performed according to the PRISMA® statement and the PICOS guidelines in the Web of Science (WOS) and Scopus databases, including selected data obtained up to 24 October 2021. The search included studies where l-C or glycine-propionyl l-Carnitine (GPL-C) supplementation was compared with a placebo in an identical situation and tested its effects on high and/or low-moderate performance. The trials that used the supplementation of l-C together with additional supplements were eliminated. There were no applied filters on physical fitness level, race, or age of the participants. The methodological quality of studies was evaluated by the McMaster Critical Review Form. Of the 220 articles obtained, 11 were finally included in this systematic review. Six studies used l-C, while three studies used l-CLT, and two others combined the molecule propionyl l-Carnitine (PL-C) with GPL-C. Five studies analyzed chronic supplementation (4-24 weeks) and six studies used an acute administration (<7 days). The administration doses in this chronic supplementation varied from 1 to 3 g/day; in acute supplementation, oral l-C supplementation doses ranged from 3 to 4 g. On the one hand, the effects of oral l-C supplementation on high-intensity exercise performance variables were analyzed in nine studies. Four of them measured the effects of chronic supplementation (lower rating of perceived exertion (RPE) after 30 min at 80% V˙O2 max on cycle ergometer and higher work capacity in "all-out" tests, peak power in a Wingate test, and the number of repetitions and volume lifted in leg press exercises), and five studies analyzed the effects of acute supplementation (lower RPE after graded exercise test on the treadmill until exhaustion and higher peak and average power in the Wingate cycle ergometer test). On the other hand, the effects of l-C supplementation on moderate exercise performance variables were observed in six studies. Out of those, three measured the effect of an acute supplementation, and three described the effect of a chronic supplementation, but no significant improvements on performance were found. In summary, l-C supplementation with 3 to 4 g ingested between 60 and 90 min before testing or 2 to 2.72 g/day for 9 to 24 weeks improved high-intensity exercise performance. However, chronic or acute l-C or GPL-C supplementation did not present improvements on moderate exercise performance.


Assuntos
Desempenho Atlético/fisiologia , Carnitina/administração & dosagem , Carnitina/farmacologia , Suplementos Nutricionais , Exercício Físico/fisiologia , Fenômenos Fisiológicos da Nutrição Esportiva/fisiologia , Administração Oral , Feminino , Humanos , Masculino , Fatores de Tempo
2.
Nutrients ; 13(12)2021 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-34959943

RESUMO

Manipulating dietary macronutrient intake may modulate adaptive responses to exercise, and improve endurance performance. However, there is controversy as to the impact of short-term dietary modification on athletic performance. In a parallel-groups, repeated measures study, 16 trained endurance runners (maximal oxygen uptake (V˙O2max): 64.2 ± 5.6 mL·kg-1·min-1) were randomly assigned to, and provided with, either a high-protein, reduced-carbohydrate (PRO) or a high-carbohydrate (CHO) isocaloric-matched diet. Participants maintained their training load over 21-consecutive days with dietary intake consisting of 7-days habitual intake (T1), 7-days intervention diet (T2) and 7-days return to habitual intake (T3). Following each 7-day dietary period (T1-T3), a micro-muscle biopsy was taken for assessment of gene expression, before participants underwent laboratory assessment of a 10 km treadmill run at 75% V˙O2max, followed by a 95% V˙O2max time to exhaustion (TTE) trial. The PRO diet resulted in a modest change (1.37-fold increase, p = 0.016) in AMPK expression, coupled with a significant increase in fat oxidation (0.29 ± 0.05 to 0.59 ± 0.05 g·min-1, p < 0.0001). However, a significant reduction of 23.3% (p = 0.0003) in TTE post intervention was observed; this reverted back to pre levels following a return to the habitual diet. In the CHO group, whilst no change in sub-maximal fuel utilisation occurred at T2, a significant 6.5% increase in TTE performance (p = 0.05), and a modest, but significant, increase in AMPK (p = 0.042) and PPAR (p = 0.029) mRNA expression compared to T1 were observed; with AMPK (p = 0.011) and PPAR (p = 0.044) remaining significantly elevated at T3. In conclusion, a 7-day isocaloric high protein diet significantly compromised high intensity exercise performance in trained runners with no real benefit on gene markers of training adaptation. A significant increase in fat oxidation during submaximal exercise was observed post PRO intervention, but this returned to pre levels once the habitual diet was re-introduced, suggesting that the response was driven via fuel availability rather than cellular adaptation. A short-term high protein, low carbohydrate diet in combination with endurance training is not preferential for endurance running performance.


Assuntos
Desempenho Atlético/fisiologia , Dieta Rica em Proteínas , Carboidratos da Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Ingestão de Alimentos/fisiologia , Metabolismo Energético , Corrida de Maratona/fisiologia , Condicionamento Físico Humano/fisiologia , Resistência Física/fisiologia , Fenômenos Fisiológicos da Nutrição Esportiva/fisiologia , Proteínas Quinases Ativadas por AMP/metabolismo , Adolescente , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/metabolismo , Consumo de Oxigênio , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Adulto Jovem
3.
PLoS One ; 16(11): e0258123, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34793475

RESUMO

BACKGROUND: Nutrition knowledge (NK) is a modifiable determinant of diet intake and can positively influence athletic performance. This study aimed to (1) adapt and translate a validated general and sports NK questionnaire into Arabic (2) assess the NK of Jordanian sportspeople, and (3) evaluate the relationship between NK and various sociodemographic factors. METHODS: The Abridged Nutrition for Sport Knowledge Questionnaire (ANSKQ) was translated into Arabic using forward-backward translation and underwent pilot testing and psychometric validation (internal consistency, test-retest reliability, inter-rater agreement) using a convenience sample of 30 individuals. Following ANSKQ validation, athletes a from 50 sport institutes in Jordan were invited (via email) to complete the Arabic ANSKQ online. Differences in NK based on demographics were analysed using t-test or ANOVA for continuous variables and chi-square tests for categorical variables. The ability of demographic factors to predict NK score-category (poor/good/average/excellent) was assessed using multivariate logistic regression. RESULTS: The Arabic ANSKQ had excellent internal consistency (Cronbach's alpha = 0.92), test-retest reliability (Pearson r = 0.926) and inter-rater agreement (Cohen's k statistic = 0.89). A total of 3636 eligible participants completed the Arabic ANSKQ. Participants were mostly athletes (91.4%), female (68.0%), had normal BMI (50.6%), and played high-intensity sports (59.6%). 88.3% of participants had poor NK (<50%). There were statistically significant differences in NK score based on participant role (athlete vs coach), age, gender, BMI, nationality, smoking, years playing sport, sport frequency, sport intensity, and nutrition training. Multivariate modelling showed participant role, BMI, education level, sport frequency and nutrition training were predictors of NK category. CONCLUSIONS: In conclusion, Jordanian sportspeople have poor NK and may benefit from increased nutrition training.


Assuntos
Atletas , Desempenho Atlético/fisiologia , Fenômenos Fisiológicos da Nutrição Esportiva/fisiologia , Ciências da Nutrição e do Esporte/tendências , Adulto , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Jordânia/epidemiologia , Masculino , Fatores Sociodemográficos , Inquéritos e Questionários , Adulto Jovem
4.
J Int Soc Sports Nutr ; 18(1): 58, 2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34419082

RESUMO

BACKGROUND: Exercise increases skeletal muscle reactive oxygen species (ROS) production, which may contribute to the onset of muscular fatigue and impair athletic performance. Mitochondria-targeted antioxidants such as MitoQ, which contains a ubiquinone moiety and is targeted to mitochondria through the addition of a lipophilic triphenylphosphonium cation, are becoming popular amongst active individuals as they are designed to accumulate within mitochondria and may provide targeted protection against exercise-induced oxidative stress. However, the effect of MitoQ supplementation on cycling performance is currently unknown. Here, we investigate whether MitoQ supplementation can improve cycling performance measured as time to complete an 8 km time trial. METHOD: In a randomized, double-blind, placebo-controlled crossover study, 19 middle-aged (age: 44 ± 4 years) recreationally trained (VO2peak: 58.5 ± 6.2 ml·kg- 1·min- 1, distance cycled per week during 6 months prior to study enrollment: 158.3 ± 58.4 km) male cyclists completed 45 min cycling at 70% VO2peak followed by an 8 km time trial after 28 days of supplementation with MitoQ (20 mg·day- 1) and a placebo. Free F2-isoprostanes were measured in plasma samples collected at rest, after 45 min cycling at 70% VO2peak and after completion of the time trial. Respiratory gases and measures of rating of perceived exertion (RPE) were also collected. RESULTS: Mean completion time for the time trial was 1.3% faster with MitoQ (12.91 ± 0.94 min) compared to placebo (13.09 ± 0.95 min, p = 0.04, 95% CI [0.05, 2.64], d = 0.2). There was no difference in RPE during the time trial between conditions (p = 0.82) despite there being a 4.4% increase in average power output during the time trial following MitoQ supplementation compared to placebo (placebo; 270 ± 51 W, MitoQ; 280 ± 53 W, p = 0.04, 95% CI [0.49, 8.22], d = 0.2). Plasma F2-isoprostanes were lower on completion of the time trial following MitoQ supplementation (35.89 ± 13.6 pg·ml- 1) compared to placebo (44.7 ± 16.9 pg·ml- 1 p = 0.03). CONCLUSION: These data suggest that MitoQ supplementation may be an effective nutritional strategy to attenuate exercise-induced increases in oxidative damage to lipids and improve cycling performance.


Assuntos
Antioxidantes/farmacologia , Desempenho Atlético/fisiologia , Ciclismo/fisiologia , Mitocôndrias Musculares/efeitos dos fármacos , Compostos Organofosforados/farmacologia , Substâncias para Melhoria do Desempenho/farmacologia , Ubiquinona/análogos & derivados , Adulto , Antioxidantes/metabolismo , Estudos Cross-Over , Método Duplo-Cego , F2-Isoprostanos/sangue , Humanos , Peroxidação de Lipídeos , Masculino , Pessoa de Meia-Idade , Mitocôndrias Musculares/metabolismo , Músculo Esquelético/metabolismo , Compostos Organofosforados/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Consumo de Oxigênio , Substâncias para Melhoria do Desempenho/metabolismo , Esforço Físico/efeitos dos fármacos , Esforço Físico/fisiologia , Placebos/metabolismo , Placebos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Fenômenos Fisiológicos da Nutrição Esportiva/efeitos dos fármacos , Fenômenos Fisiológicos da Nutrição Esportiva/fisiologia , Fatores de Tempo , Ubiquinona/metabolismo , Ubiquinona/farmacologia
5.
Nutrients ; 13(6)2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-34071868

RESUMO

This investigation aimed to determine the effect of a multi-ingredient pre-workout supplement (MIPS) on heart rate (HR), perceived exertion (RPE), lactate concentration, and time to fatigue (TTF) during a running task to volitional exhaustion. Eleven NCAA Division I cross-country runners (20 ± 2 year; height: 171 ± 14 cm; weight: 63.5 ± 9.1 kg) participated in this randomized, double-blind, placebo-controlled cross-over study. Bayesian statistical methods were utilized, and parameter estimates were interpreted as statistically significant if the 95% highest-density intervals (HDIs) did not include zero. TTF was increased in the MIPS condition with a posterior Meandiff = 154 ± 4.2 s (95% HDI: -167, 465) and a 0.84 posterior probability that the supplement would increase TTF relative to PL. Blood lactate concentration immediately post-exercise was also higher in the MIPS condition compared to PL with an estimated posterior Meandiff = 3.99 ± 2.1 mmol (95% HDI: -0.16, 7.68). There were no differences in HR or RPE between trials. These findings suggest that a MIPS ingested prior to sustained running at lactate threshold has an 84% chance of increasing TTF in highly trained runners and may allow athletes to handle a higher level of circulating lactate before reaching exhaustion.


Assuntos
Suplementos Nutricionais , Fadiga Muscular , Fenômenos Fisiológicos da Nutrição Esportiva , Adolescente , Adulto , Atletas , Beta vulgaris , Cafeína , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Ácido Láctico/metabolismo , Masculino , Fadiga Muscular/efeitos dos fármacos , Fadiga Muscular/fisiologia , Substâncias para Melhoria do Desempenho/administração & dosagem , Substâncias para Melhoria do Desempenho/farmacologia , Resistência Física/efeitos dos fármacos , Resistência Física/fisiologia , Corrida/fisiologia , Fenômenos Fisiológicos da Nutrição Esportiva/efeitos dos fármacos , Fenômenos Fisiológicos da Nutrição Esportiva/fisiologia , Adulto Jovem
6.
Clin Nutr ; 40(4): 1495-1502, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33743284

RESUMO

BACKGROUND & AIMS: The aim of this paper was to investigate and compare the effects of two iso-energetic hypo-caloric ketogenic hyper-ketonemic and non-ketogenic low carbohydrate high fat high cholesterol diets on body-composition, muscle strength and hormonal profile in experienced resistance-trained middle-aged men. METHODS: Twenty non-competitive experienced resistance-trained middle-aged men were on the supervised calorie maintenance western diet and resistance-training regimen for 4 weeks and then divided into ketogenic and non-ketogenic groups for 8 weeks period. Keto bodies (ß-hydroxybutyrate) levels were measured weekly, testosterone and insulin biweekly, strength and body-composition monthly, lipid profile and blood sugar level at the beginning and at the end of the study. RESULTS: Both groups lost a similar amount of lean body mass and fat tissue (from F = 248.665, p < 0.001 to F = 21.943, p = 0.001), but preserved maximal upper and lower body strength (from F = 1.772, p = 0.238 to F = 0.595, p = 0.577). Basal testosterone and free testosterone increased (from F = 37.267, p = 0.001 to F = 16.261, p = 0.005) and insulin levels decreased significantly in both groups (F = 27.609, p = 0.001; F = 54.256, p < 0.001, respectively). No differences in lipid profile and blood sugar level were found (from F = 4.174, p = 0.058, to F = 0.065, p = 0.802). CONCLUSIONS: Ketogenic diet with sustained hyper-ketonemia above 1 mol/l has the same impact as low carbohydrate non-ketogenic diet on muscle strength, body-composition, and hormonal and lipid profile in hypo-caloric dietary conditions in strength-trained middle-aged men.


Assuntos
Composição Corporal/fisiologia , Dieta Cetogênica/métodos , Lipídeos/sangue , Força Muscular/fisiologia , Fenômenos Fisiológicos da Nutrição Esportiva/fisiologia , Testosterona/sangue , Adulto , Glicemia/metabolismo , Restrição Calórica/métodos , Ingestão de Energia/fisiologia , Voluntários Saudáveis , Humanos , Insulina/sangue , Masculino , Treinamento Resistido , Redução de Peso/fisiologia
7.
Nutrients ; 13(2)2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33540813

RESUMO

Endurance athletes need a regular and well-detailed nutrition program in order to fill their energy stores before training/racing, to provide nutritional support that will allow them to endure the harsh conditions during training/race, and to provide effective recovery after training/racing. Since exercise-related gastrointestinal symptoms can significantly affect performance, they also need to develop strategies to address these issues. All these factors force endurance athletes to constantly seek a better nutritional strategy. Therefore, several new dietary approaches have gained interest among endurance athletes in recent decades. This review provides a current perspective to five popular diet approaches: (a) vegetarian diets, (b) high-fat diets, (c) intermittent fasting diets, (d) gluten-free diet, and (e) low fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAP) diets. We reviewed scientific studies published from 1983 to January 2021 investigating the impact of these popular diets on the endurance performance and health aspects of endurance athletes. We also discuss all the beneficial and harmful aspects of these diets, and offer key suggestions for endurance athletes to consider when following these diets.


Assuntos
Atletas , Desempenho Atlético/fisiologia , Dieta/tendências , Fenômenos Fisiológicos da Nutrição Esportiva/fisiologia , Esportes/fisiologia , Dieta/efeitos adversos , Dieta Livre de Glúten , Dieta Hiperlipídica , Dieta Vegetariana , Carboidratos da Dieta/administração & dosagem , Carboidratos da Dieta/metabolismo , Jejum , Fermentação , Gastroenteropatias/etiologia , Gastroenteropatias/prevenção & controle , Humanos , Necessidades Nutricionais , Resistência Física
8.
J Sci Med Sport ; 24(1): 7-12, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32624442

RESUMO

OBJECTIVES: To investigate the relationship between dietary intake, meal timing and sleep in elite male Australian football players. DESIGN: Prospective cohort study. METHODS: Sleep and dietary intake were assessed in 36 elite male Australian Football League (AFL) players for 10 consecutive days in pre-season. Sleep was examined using wrist activity monitors and sleep diaries. Dietary intake was analysed using the smartphone application MealLogger and FoodWorks. Generalised linear mixed models examined the associations between diet [total daily and evening (>6pm) energy, protein, carbohydrate, sugar and fat intake] and sleep [total sleep time (TST), sleep efficiency (SE), wake after sleep onset (WASO) and sleep onset latency (SOL)]. RESULTS: Total daily energy intake (MJ) was associated with a longer WASO [ß=3, 95%CI: 0.2-5; p=0.03] and SOL [ß=5, 95%CI: 1-9; p=0.01]. Total daily protein intake (gkg-1) was associated with longer WASO [ß=4, 95%CI: 0.8-7; p=0.01] and reduced SE [ß=-0.7 CI: -1.3 to -0.2; p=0.006], while evening protein intake (gkg-1) was associated with shortened SOL [ß=-2, 95%CI: -4 to -0.4), p=0.02]. Evening sugar intake (gkg-1) was associated with shorter TST [ß=-5, 95%CI: -10 to -0.6; p=0.03] and WASO [ß=-1, 95%CI: -2 to -0.3; p=0.005]. A longer period between the evening meal consumption and bedtime was associated with a shorter TST [ß=-8, 95%CI: -16 to -0.3; p=0.04]. CONCLUSIONS: Evening dietary factors, including sugar and protein intake, had the greatest association with sleep in elite male AFL players. Future research manipulating these dietary variables to determine cause and effect relationships, could guide dietary recommendations to improve sleep in athletes.


Assuntos
Ingestão de Alimentos , Ingestão de Energia , Refeições , Sono , Esportes , Humanos , Masculino , Adulto Jovem , Actigrafia , Registros de Dieta , Proteínas Alimentares/administração & dosagem , Açúcares da Dieta/administração & dosagem , Aplicativos Móveis , Estudos Prospectivos , Sono/fisiologia , Smartphone , Fenômenos Fisiológicos da Nutrição Esportiva/fisiologia , Fatores de Tempo
9.
Nutrients ; 12(12)2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33317139

RESUMO

Preworkout multi-ingredient admixtures are used to maximise exercise performance. The present double-blind, cross-over study compared the acute effects of ingesting a preworkout multi-ingredient (PREW) admixture vs. carbohydrate (CHO) over a week (microcycle) comprising three resistance training (RT) workouts alternated with two 30-min low-intensity endurance sessions (END) on RT volume (kg lifted) and END substrate oxidation. Additionally, postworkout decreases of muscle function and subjective responses were analysed. Following a baseline assessment, fourteen recreationally trained, middle-aged adults (seven females, 48.8 ± 4.7 years old) completed two identical microcycles separated by a two-week washout period while receiving either PREW or CHO (15 min prior to workout). The RT volume, per session (SVOL) and for the entire week (WVOL), was calculated. Fatty acid oxidation (FAO) during 30-min cycling corresponding to their individually determined maximal fat oxidation was measured using expired gasses and indirect calorimetry. Assessments of performance and tensiomyography were conducted within 20 min after each RT. Higher (p = 0.001) SVOL and WVOL along with a larger proportion of FAO (p = 0.05) during the second END workout were determined under the PREW treatment. No other statistically significant differences were observed between conditions. Compared to CHO, a preworkout multi-ingredient appears to increase resistance volume and favour fat oxidation during low-intensity endurance exercises.


Assuntos
Suplementos Nutricionais , Treino Aeróbico/métodos , Metabolismo dos Lipídeos/efeitos dos fármacos , Treinamento Resistido/métodos , Fenômenos Fisiológicos da Nutrição Esportiva/efeitos dos fármacos , Calorimetria Indireta , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Metabolismo dos Lipídeos/fisiologia , Masculino , Pessoa de Meia-Idade , Fenômenos Fisiológicos da Nutrição Esportiva/fisiologia
10.
Nutrients ; 12(10)2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33076263

RESUMO

Research has suggested that nutrient, exercise, and metabolism-related proteins interact to regulate mammalian target of rapamycin complex one (mTOR) post-exercise and their interactions needs clarification. In a double-blind, cross-over, repeated measures design, ten participants completed four sets to failure at 70% of 1-repitition maximum (1-RM) with 45 s rest on angled leg press with or without pre-exercise maltodextrin (2 g/kg) after a 3 h fast. Vastus lateralis biopsies were collected at baseline before supplementation and 1 h post-exercise to analyze Focal Adhesion Kinase (FAK), ribosomal protein S6 kinase beta-1 (p70S6K), insulin receptor substrate 1 (IRS-1), phosphatidylinositol 3-kinase (PI3K), and 5' AMP-activated protein kinase (AMPK) activation. FAK and IRS-1 activity were only elevated 1 h post-exercise with carbohydrate ingestion (p < 0.05). PI3K and p70S6K activation were both elevated after exercise in both conditions (p < 0.05). However, AMPK activity did not change from baseline in both conditions (p > 0.05). We conclude that FAK does not induce mTOR activation through PI3K crosstalk in response to exercise alone. In addition, FAK may not be regulated by AMPK catalytic activity, but this needs further research. Interestingly, carbohydrate-induced insulin signaling appears to activate FAK at the level of IRS-1 but did not enhance mTOR activity 1 h post-exercise greater than the placebo condition. Future research should investigate these interactions under different conditions and within different time frames to clearly understand the interactions between these signaling molecules.


Assuntos
Carboidratos da Dieta/farmacologia , Ingestão de Alimentos/fisiologia , Exercício Físico/fisiologia , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Insulina/metabolismo , Mecanotransdução Celular/fisiologia , Nutrientes/farmacologia , Transdução de Sinais/fisiologia , Fenômenos Fisiológicos da Nutrição Esportiva/fisiologia , Adulto , Carboidratos da Dieta/administração & dosagem , Humanos , Proteínas Substratos do Receptor de Insulina/metabolismo , Masculino , Fosfatidilinositol 3-Quinase/metabolismo , Polissacarídeos/administração & dosagem , Polissacarídeos/farmacologia , Serina-Treonina Quinases TOR , Adulto Jovem
11.
Nutrients ; 12(11)2020 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-33113759

RESUMO

BACKGROUND: Low energy availability (LEA) is a major problem as athletes often restrict their energy intake. It has been shown that LEA occurs often in female and endurance athletes and in athletes from weight-sensitive or aesthetic sports. The purpose of this study was to investigate energy availability (EA) in elite wheelchair athletes. METHODS: Fourteen elite wheelchair athletes (8 males; 6 females) participated. Data were collected using a weighed seven-day food and training diary to estimate energy intake and exercise energy expenditure. Resting energy expenditure and body composition were measured, whereas energy balance (EB) was calculated. RESULTS: Measured over 7 days, EA was significantly different (36.1 ± 6.7 kcal kg-1 FFM day-1) in male compared to female (25.1 ± 7.1 kcal kg-1 FFM day-1) athletes (p < 0.001). From all analyzed days, LEA occurred in 73% of the days in female athletes and in 30% of the days in male athletes. EB was positive in male athletes (+169.1 ± 304.5 kcal) and negative (-288.9 ± 304.8 kcal) in female athletes. CONCLUSIONS: A higher prevalence of LEA was found in female compared to male athletes. A higher energy intake would be recommended to meet energy needs and to maximize training adaptation.


Assuntos
Ingestão de Energia/fisiologia , Metabolismo Energético/fisiologia , Fatores Sexuais , Fenômenos Fisiológicos da Nutrição Esportiva/fisiologia , Esportes para Pessoas com Deficiência/fisiologia , Adulto , Metabolismo Basal , Composição Corporal , Registros de Dieta , Feminino , Humanos , Masculino , Estado Nutricional , Paratletas , Fatores de Tempo
12.
Nutrients ; 12(10)2020 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-33050111

RESUMO

Chronic kidney disease (CKD) is associated with aggravating factors which can affect both body composition and nutritional status. The purpose of the present systematic review was to investigate the potential effects of any physical activity on body composition or nutritional status among patients with stage 5 CKD undergoing hemodialysis (HD). A literature search on PubMed, Scopus, Web of Science, Google Scholar, and Cochrane was conducted and 14 randomized clinical trials were included. Skeletal muscle index and mid-arm muscular circumference increased after resistance exercise, and the results on body mass index, % body fat, and lean body mass varied. Serum albumin and C-reactive protein, in most cases, showed a slight increase and decrease, respectively. An improvement was also observed in body strength and overall performance status. The results suggest that physical activity can be beneficial for both the body composition and nutritional status of patients undergoing HD and can help in the prevention of sarcopenia. However, further research is needed mainly in the field of nutritional status.


Assuntos
Composição Corporal , Exercício Físico/fisiologia , Falência Renal Crônica/metabolismo , Falência Renal Crônica/fisiopatologia , Estado Nutricional , Diálise Renal , Fenômenos Fisiológicos da Nutrição Esportiva/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteína C-Reativa/metabolismo , Feminino , Humanos , Falência Renal Crônica/complicações , Masculino , Pessoa de Meia-Idade , Sarcopenia/etiologia , Sarcopenia/prevenção & controle , Albumina Sérica/metabolismo , Adulto Jovem
13.
Nutrients ; 12(8)2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32824034

RESUMO

An adequate and balanced diet is of utmost importance in recovery and rehabilitation. "Rehabilitation nutrition" for injury recovery of athletes is similar to sports nutrition, except for the differences that concern the prevention of the risk or presence of sarcopenia, malnutrition, or dysphagia. Rehabilitation nutrition also aims, combined with training, to an adequate long-term nutritional status of the athlete and also in physical condition improvement, in terms of endurance and resistance. The aim of this paper is to define the proper nutrition for athletes in order to hasten their return to the sports after surgery or injury. Energy intake should be higher than the energy target in order to fight sarcopenia-that is 25-30 kcal/kg of body weight. Macro- and micro-nutrients play an important role in metabolism, energy production, hemoglobin synthesis, lean mass and bone mass maintenance, immunity, health, and protection against oxidative damage. Nutritional strategies, such as supplementation of suboptimal protein intake with leucine are feasible and effective in offsetting anabolic resistance. Thus, maintaining muscle mass, without gaining fat, becomes challenging for the injured athlete. A dietary strategy should be tailored to the athlete's needs, considering amounts, frequency, type and, most of all, protein quality. During rehabilitation, simultaneous carbohydrates and protein intake can inhibit muscle breakdown and muscle atrophy. The long-term intake of omega-3 fatty acids enhances anabolic sensitivity to amino acids; thus, it may be beneficial to the injured athlete. Adequate intakes of macronutrients can play a major role supporting athletes' anabolism.


Assuntos
Traumatismos em Atletas/metabolismo , Traumatismos em Atletas/reabilitação , Suplementos Nutricionais , Ingestão de Alimentos/fisiologia , Fenômenos Fisiológicos da Nutrição Esportiva/fisiologia , Tecido Adiposo/metabolismo , Traumatismos em Atletas/complicações , Traumatismos em Atletas/fisiopatologia , Transtornos de Deglutição/etiologia , Transtornos de Deglutição/prevenção & controle , Proteínas Alimentares/administração & dosagem , Ingestão de Energia , Ácidos Graxos Ômega-3/administração & dosagem , Humanos , Leucina/administração & dosagem , Desnutrição/etiologia , Desnutrição/prevenção & controle , Músculo Esquelético/metabolismo , Recuperação de Função Fisiológica , Risco , Sarcopenia/etiologia , Sarcopenia/prevenção & controle
14.
Nutrients ; 12(8)2020 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-32824745

RESUMO

Periodized nutrition is necessary to optimize training and enhance performance through the season. The Athlete's Plate (AP) is a nutrition education tool developed to teach athletes how to design their plates depending on training load (e.g., volume × intensity), from easy (E), moderate (M) to hard (H). The AP was validated, confirming its recommendations according to international sports nutrition guidelines. However, the AP had significantly higher protein content than recommended (up to 2.9 ± 0.5 g·kg-1·d-1; p < 0.001 for H male). The aim of this study was to quantify the environmental impact (EnvI) of the AP and to evaluate the influence of meal type, training load, sex and registered dietitian (RD). The nutritional contents of 216 APs created by 12 sport RDs were evaluated using Computrition Software (Hospitality Suite, v. 18.1, Chatsworth, CA, USA). The EnvI of the AP was analyzed by life cycle assessment (LCA) expressed by the total amount of food on the AP, kg, and kcal, according to the Swiss Agricultural Life Cycle Assessment (SALCA) methodology. Higher EnvI is directly associated with higher training load when the total amount of food on the plate is considered for E (5.7 ± 2.9 kg CO2 eq/day); M (6.4 ± 1.5 kg CO2 eq/day); and H (8.0 ± 2.1 kg CO2 eq/day). Global warming potential, exergy and eutrophication are driven by animal protein and mainly beef, while ecotoxicity is influenced by vegetable content on the AP. The EnvI is influenced by the amount of food, training load and sex. This study is the first to report the degree of EnvI in sports nutrition. These results not only raise the need for sustainability education in sports nutrition in general, but also the urgency to modify the AP nutrition education tool to ensure sports nutrition recommendations are met, while not compromising the environment.


Assuntos
Atletas/educação , Desempenho Atlético/fisiologia , Ingestão de Alimentos/fisiologia , Ingestão de Energia/fisiologia , Meio Ambiente , Educação em Saúde/métodos , Recomendações Nutricionais , Fenômenos Fisiológicos da Nutrição Esportiva/fisiologia , Ciências da Nutrição e do Esporte/educação , Feminino , Aquecimento Global , Humanos , Estágios do Ciclo de Vida , Masculino , Refeições , Política Nutricional , Necessidades Nutricionais , Condicionamento Físico Humano/fisiologia
15.
Nutrients ; 12(9)2020 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-32824885

RESUMO

Beta-alanine supplementation (BA) has a positive impact on physical performance. However, evidence showing a benefit of this amino acid in aerobic-anaerobic transition zones is scarce and the results controversial. The aim of this systematic review and meta-analysis is to analyze the effects of BA supplementation on physical performance in aerobic-anaerobic transition zones. At the same time, the effect of different dosages and durations of BA supplementation were identified. The search was designed in accordance with the PRISMA® guidelines for systematic reviews and meta-analyses and performed in Web of Science (WOS), Scopus, SPORTDiscus, PubMed, and MEDLINE between 2010 and 2020. The methodological quality and risk of bias were evaluated with the Cochrane Collaboration tool. The main variables were the Time Trial Test (TTT) and Time to Exhaustion (TTE) tests, the latter separated into the Limited Time Test (LTT) and Limited Distance Test (LDT). The analysis was carried out with a pooled standardized mean difference (SMD) through Hedges' g test (95% CI). Nineteen studies were included in the systematic review and meta-analysis, revealing a small effect for time in the TTT (SMD, -0.36; 95% CI, -0.87-0.16; I2 = 59%; p = 0.010), a small effect for LTT (SMD, 0.25; 95% CI, -0.01-0.51; I2 = 0%; p = 0.53), and a large effect for LDT (SMD, 4.27; 95% CI, -0.25-8.79; I2 = 94%; p = 0.00001). BA supplementation showed small effects on physical performance in aerobic-anaerobic transition zones. Evidence on acute supplementation is scarce (one study); therefore, exploration of acute supplementation with different dosages and formats on physical performance in aerobic-anaerobic transition zones is needed.


Assuntos
Aerobiose/fisiologia , Anaerobiose/fisiologia , Suplementos Nutricionais , Desempenho Físico Funcional , Fenômenos Fisiológicos da Nutrição Esportiva/fisiologia , beta-Alanina/administração & dosagem , Aerobiose/efeitos dos fármacos , Anaerobiose/efeitos dos fármacos , Humanos , beta-Alanina/farmacologia
16.
Nutrients ; 12(9)2020 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-32824920

RESUMO

The aim of the present study was to analyze the effect of creatine (Cr) supplementation on peak torque (PT) and fatigue rate in Paralympic weightlifting athletes. Eight Paralympic powerlifting athletes participated in the study, with 25.40 ± 3.30 years and 70.30 ± 12.15 kg. The measurements of muscle strength, fatigue index (FI), peak torque (PT), force (kgf), force (N), rate of force development (RFD), and time to maximum isometric force (time) were determined by a Musclelab load cell. The study was performed in a single-blind manner, with subjects conducting the experiments first with placebo supplementation and then, following a 7-day washout period, beginning the same protocol with creatine supplementation for 7 days. This sequence was chosen because of the lengthy washout of creatine. Regarding the comparison between conditions, Cr supplementation did not show effects on the variables of muscle force, peak torque, RFD, and time to maximum isometric force (p > 0.05). However, when comparing the results of the moments with the use of Cr and placebo, a difference was observed for the FI after seven days (U3: 1.12; 95% CI: (0.03, 2.27); p = 0.02); therefore, the FI was higher for placebo. Creatine supplementation has a positive effect on the performance of Paralympic powerlifting athletes, reducing fatigue index, and keeping the force levels as well as PT.


Assuntos
Creatina/administração & dosagem , Suplementos Nutricionais , Fadiga Muscular/efeitos dos fármacos , Força Muscular/efeitos dos fármacos , Músculo Esquelético/fisiologia , Paratletas , Fenômenos Fisiológicos da Nutrição Esportiva/fisiologia , Levantamento de Peso/fisiologia , Adulto , Brasil , Creatina/farmacologia , Humanos , Contração Isométrica/efeitos dos fármacos , Masculino , Método Simples-Cego , Torque , Adulto Jovem
17.
Nutrients ; 12(9)2020 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-32824957

RESUMO

Interest in low-carbohydrate, high-fat (LCHF) diets has increased over recent decades given the theorized benefit of associated intramuscular adaptations and shifts in fuel utilization on endurance exercise performance. Consuming a LCHF diet during exercise training increases the availability of fat (i.e., intramuscular triglyceride stores; plasma free fatty acids) and decreases muscle glycogen stores. These changes in substrate availability increase reliance on fat oxidation for energy production while simultaneously decreasing reliance on carbohydrate oxidation for fuel during submaximal exercise. LCHF diet-mediated changes in substrate oxidation remain even after endogenous or exogenous carbohydrate availability is increased, suggesting that the adaptive response driving changes in fat and carbohydrate oxidation lies within the muscle and persists even when the macronutrient content of the diet is altered. This narrative review explores the intramuscular adaptations underlying increases in fat oxidation and decreases in carbohydrate oxidation with LCHF feeding. The possible effects of LCHF diets on protein metabolism and post-exercise muscle remodeling are also considered.


Assuntos
Adaptação Fisiológica/fisiologia , Dieta com Restrição de Carboidratos , Dieta Hiperlipídica , Exercício Físico/fisiologia , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiologia , Fenômenos Fisiológicos da Nutrição Esportiva/fisiologia , Transporte Biológico , Carboidratos da Dieta/metabolismo , Gorduras na Dieta/metabolismo , Metabolismo Energético , Ácidos Graxos não Esterificados/sangue , Glucose/metabolismo , Glicogênio/metabolismo , Humanos , Oxirredução , Triglicerídeos/metabolismo
18.
Nutrients ; 12(7)2020 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-32708396

RESUMO

Aging is accompanied by a progressive decline in muscle mass and an increase in fat mass, which are detrimental changes associated with the development of health conditions such as type-2 diabetes mellitus or chronic low-grade inflammation. Although both exercise as well as nutritional interventions are known to be beneficial in counteracting those age-related changes, data to which extent untrained elderly people may benefit is still sparse. Therefore, a randomized, controlled, 12-week interventional trial was conducted in which 134 healthy untrained participants (96 women and 38 men, age 59.4 ± 5.6 years, body mass index (BMI) 28.4 ± 5.8 kg/m2) were allocated to one of four study groups: (1) control group with no intervention (CON); (2) 2×/week aerobic and resistance training only (EX); (3) exercise routine combined with dietary counseling in accordance with the guidelines of the German Nutrition Society (EXDC); (4) exercise routine combined with intake of 2 g/day oil from Calanus finmarchicus (EXCO). Body composition (bioelectrical impedance analysis), as well as markers of glucose metabolism and blood lipids, were analyzed at the beginning and the end of the study. The highest decreases in body fat were observed within the EXCO group (-1.70 ± 2.45 kg, p < 0.001), and the EXDC (-1.41 ± 2.13 kg, p = 0.008) group. Markers of glucose metabolism and blood lipids remained unchanged in all groups. Taken together results of this pilot study suggest that a combination of moderate exercise and intake of oil from Calanus finmarchicus or a healthy diet may promote fat loss in elderly untrained overweight participants.


Assuntos
Tecido Adiposo/metabolismo , Envelhecimento/metabolismo , Composição Corporal , Copépodes/química , Dieta Saudável , Gorduras Insaturadas na Dieta/administração & dosagem , Suplementos Nutricionais , Fenômenos Fisiológicos da Nutrição do Idoso/fisiologia , Exercício Físico/fisiologia , Glucose/metabolismo , Metabolismo dos Lipídeos , Sobrepeso/metabolismo , Sobrepeso/terapia , Fenômenos Fisiológicos da Nutrição Esportiva/fisiologia , Fatores Etários , Idoso , Animais , Gorduras Insaturadas na Dieta/isolamento & purificação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto
19.
Nutrients ; 12(7)2020 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-32708555

RESUMO

The present study investigated whether the caffeine supplementation for four days would induce tolerance to the ergogenic effects promoted by acute intake on physiological, metabolic, and performance parameters of cyclists. A double-blind placebo-controlled cross-over design was employed, involving four experimental trials; placebo (4-day)-placebo (acute)/PP, placebo (4-day)-caffeine (acute)/PC, caffeine (4-day)-caffeine (acute)/CC and caffeine (4-day)-placebo (acute)/CP. Fourteen male recreationally-trained cyclists ingested capsules containing either placebo or caffeine (6 mg∙kg-1) for 4 days. On day 5 (acute), capsules containing placebo or caffeine (6 mg∙kg-1) were ingested 60 min before completing a 16 km time-trial (TT). CC and PC showed improvements in time (3.54%, ES = 0.72; 2.53%, ES = 0.51) and in output power (2.85%, ES = 0.25; 2.53%, ES = 0.20) (p < 0.05) compared to CP and PP conditions, respectively. These effects were accompanied by increased heart rate (2.63%, ES = 0.47; 1.99%, ES = 0.34), minute volume (13.11%, ES = 0.61; 16.32%, ES = 0.75), expired O2 fraction (3.29%, ES = 0.96; 2.87, ES = 0.72), lactate blood concentration (immediately after, 29.51% ES = 0.78; 28.21% ES = 0.73 recovery (10 min), 36.01% ES = 0.84; 31.22% ES = 0.81), and reduction in expired CO2 fraction (7.64%, ES = 0.64; 7.75%, ES = 0.56). In conclusion, these results indicate that caffeine, when ingested by cyclists in a dose of 6 mg∙kg-1 for 4 days, does not induce tolerance to the ergogenic effects promoted by acute intake on physiological, metabolic, and performance parameters.


Assuntos
Desempenho Atlético , Ciclismo/fisiologia , Cafeína/administração & dosagem , Cafeína/farmacologia , Suplementos Nutricionais , Substâncias para Melhoria do Desempenho , Resistência Física/efeitos dos fármacos , Fenômenos Fisiológicos da Nutrição Esportiva/fisiologia , Adulto , Glicemia , Cafeína/sangue , Estudos Cross-Over , Método Duplo-Cego , Fadiga/prevenção & controle , Feminino , Humanos , Hidrocortisona/sangue , Lactatos/sangue , Masculino , Fatores de Tempo
20.
Nutrients ; 12(5)2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-32365576

RESUMO

The individual response to nutrients and non-nutrient molecules can be largely affected by three important biological layers. The gut microbiome can alter the bioavailability of nutrients and other substances, the genome can influence molecule kinetics and dynamics, while the epigenome can modulate or amplify the properties of the genome. Today the use of omic techniques and bioinformatics, allow the construction of individual multilayer networks and thus the identification of personalized strategies that have recently been considered in all medical fields, including sports medicine. The composition of each athlete's microbiome influences sports performance both directly by acting on energy metabolism and indirectly through the modulation of nutrient or non-nutrient molecule availability that ultimately affects the individual epigenome and the genome. Among non-nutrient molecules polyphenols can potentiate physical performances through different epigenetic mechanisms. Polyphenols interact with the gut microbiota, undergoing extensive metabolism to produce bioactive molecules, which act on transcription factors involved in mitochondrial biogenesis, antioxidant systems, glucose and lipid homeostasis, and DNA repair. This review focuses on polyphenols effects in sports performance considering the individual microbiota, epigenomic asset, and the genomic characteristics of athletes to understand how their supplementation could potentially help to modulate muscle inflammation and improve recovery.


Assuntos
Desempenho Atlético/fisiologia , Diosgenina/administração & dosagem , Epigenômica , Microbioma Gastrointestinal/fisiologia , Genômica , Compostos Fitoquímicos/metabolismo , Fitosteróis/administração & dosagem , Polifenóis/administração & dosagem , Fenômenos Fisiológicos da Nutrição Esportiva/genética , Fenômenos Fisiológicos da Nutrição Esportiva/fisiologia , Disponibilidade Biológica , Metabolismo Energético , Humanos , Mitocôndrias/metabolismo , Biogênese de Organelas , Polifenóis/metabolismo , Fatores de Transcrição/fisiologia
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