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1.
J Int Soc Sports Nutr ; 18(1): 48, 2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34127014

RESUMO

BACKGROUND: This study aimed to investigate the effect of multi-ingredient intra- (BA) versus extra- (ALK) cellular buffering factor supplementation, combined with the customary intake of branched-chain amino acids (BCAA) and creatine malate (TCM), on body composition, exercise variables, and biochemical and hematological parameters in 9 elite taekwondo athletes. METHODS: Eight-week randomized double-blind crossover BA (5.0 g·day-1 of ß-alanine) versus ALK (0.07 g·kgFFM-1·day-1 of sodium bicarbonate) supplementation combined with BCAA (0.2 g·kgFFM-1·day-1) and TCM (0.05 g·kgFFM-1·day-1) during a standard 8-week taekwondo training period was implemented. In the course of the experiment, body composition (dual X-ray absorptiometry), aerobic capacity (ergospirometric measurements during an incremental treadmill test until exhaustion), and exercise blood biomarkers concentrations were measured. Data were analyzed using repeated measures within-between interaction analysis of variance with the inclusion of experimental supplementation order. RESULTS: The maximum post-exercise blood ammonia concentration decreased in both groups after supplementation (from 80.3 ± 10.6 to 72.4 ± 10.2 µmol∙L-1, p = 0.013 in BA; from 81.4 ± 8.7 to 74.2 ± 8.9 µmol∙L-1, p = 0.027 in ALK), indicating reduced exercise-related adenosine triphosphate degradation. However, no differences were found in body composition, aerobic capacity, blood lactate concentration, and hematological parameters after neither BA (combined with BCAA and TCM) nor ALK (combined with BCAA and TCM) supplementation. CONCLUSIONS: In highly trained taekwondo athletes, neither extra- nor intracellular buffering enhancement resulting from BA and ALK supplementation, combined with BCAA and TCM treatment, affects body mass and composition, maximum oxygen uptake, and hematological indices, even though certain advantageous metabolic adaptations can be observed.


Assuntos
Aminoácidos de Cadeia Ramificada/administração & dosagem , Amônia/sangue , Desempenho Atlético/fisiologia , Creatina/administração & dosagem , Suplementos Nutricionais , Artes Marciais/fisiologia , Bicarbonato de Sódio/administração & dosagem , beta-Alanina/administração & dosagem , Adaptação Fisiológica , Biomarcadores/sangue , Composição Corporal , Estudos Cross-Over , Método Duplo-Cego , Humanos
2.
J Sports Med Phys Fitness ; 61(6): 771-778, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34110118

RESUMO

BACKGROUND: Speed and throw ball in basketball players are determinant skills for basketball performance. The purpose of this study was to determinate the relationship between speed and throw the ball with jump capacity and body composition in university basketball players. METHODS: A comparative descriptive study with transversal design and a quantitative approach was performed. Seventeen male University basketball players (age = 23.60±3.45 years, height = 180.41±7.99 cm and Body Mass = 86.48±20.07 Kg) completed the following test: throwing the ball (m/s), handgrip strength (kg), speed 5-20 m (i.e., with and without the ball), jumping and reactive strength. Likewise, anthropometric variables and body composition were evaluated. RESULTS: A very high correlation was found between the throw ball and the skeletal muscle mass (r=0.810, P<0.001) dominant handgrip strength (r=0.709, P<0.001) and non-dominant handgrip strength (r=0.610, P<0.01). The throw ball reported association with skeletal muscle mass (r2=0.67, P<0.001, 67% of the variance). Significant differences were found in speed with and without the ball at 10 m (P=0.003, ES=-0.854), 15 m (P=<001, ES=-1.548) and 20 m (P=<001, ES=-1.644). The speed of displacement without ball correlated high with the countermovement jump (CMJ) (r=-0.530, P≤0.05) Abalakov (r=-0.586, P≤0.05) and Drop Jump (DJ) (r=-0.685, P≤0.01) in the first 5 m. CONCLUSIONS: The speed and throwing of the ball are associated with jumping capacity and skeletal muscle mass. Therefore, it is necessary to work these capacities in the university basketball player to improve performance.


Assuntos
Desempenho Atlético/fisiologia , Basquetebol/fisiologia , Adulto , Composição Corporal , Força da Mão/fisiologia , Humanos , Masculino , Músculo Esquelético/fisiologia , Universidades , Adulto Jovem
3.
J Int Soc Sports Nutr ; 18(1): 49, 2021 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-34147116

RESUMO

PURPOSE: Previous investigations have found positive effects of acute ingestion of capsules containing 4-to-9 mg of caffeine per kg of body mass on several aspects of judo performance. However, no previous investigation has tested the effectiveness of caffeinated chewing gum as the form of caffeine administration for judoists. The main goal of this study was to assess the effect of acute ingestion of a caffeinated chewing gum on the results of the special judo fitness test (SJFT). METHODS: Nine male elite judo athletes of the Polish national team (23.7 ± 4.4 years, body mass: 73.5 ± 7.4 kg) participated in a randomized, crossover, placebo-controlled and double-blind experiment. Participants were moderate caffeine consumers (3.1 mg/kg/day). Each athlete performed three identical experimental sessions after: (a) ingestion of two non-caffeinated chewing gums (P + P); (b) a caffeinated chewing gum and a placebo chewing gum (C + P; ~2.7 mg/kg); (c) two caffeinated chewing gums (C + C; ~5.4 mg/kg). Each gum was ingested 15 min before performing two Special Judo Fitness Test (SJFT) which were separated by 4 min of combat activity. RESULTS: The total number of throws was not different between P + P, C + P, and C + C (59.66 ± 4.15, 62.22 ± 4.32, 60.22 ± 4.08 throws, respectively; p = 0.41). A two-way repeated measures ANOVA indicated no significant substance × time interaction effect as well as no main effect of caffeine for SJFT performance, SJFT index, blood lactate concentration, heart rate or rating of perceived exertion. CONCLUSIONS: The results of the current study indicate that the use of caffeinated chewing gum in a dose up to 5.4 mg/kg of caffeine did not increase performance during repeated SJFTs.


Assuntos
Atletas , Desempenho Atlético , Cafeína/farmacologia , Estimulantes do Sistema Nervoso Central/farmacologia , Goma de Mascar , Artes Marciais/fisiologia , Desempenho Atlético/fisiologia , Desempenho Atlético/estatística & dados numéricos , Cafeína/administração & dosagem , Estimulantes do Sistema Nervoso Central/administração & dosagem , Estudos Cross-Over , Método Duplo-Cego , Frequência Cardíaca , Humanos , Ácido Láctico/sangue , Masculino , Artes Marciais/estatística & dados numéricos , Aptidão Física , Placebos/administração & dosagem , Adulto Jovem
4.
J Sports Sci ; 39(14): 1633-1660, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33956579

RESUMO

Small-sided games is a commonly used training method to develop technical, tactical and physical qualities concurrently. However, a review of small-sided games in rugby football codes (e.g. rugby union, rugby league) is not available. This systematic review aims to investigate the acute responses and chronic adaptations of small-sided games within rugby football codes considering the constraints applied. Four electronical databases were systematically searched until August 2020. Acute and chronic studies investigating rugby football codes small-sided games, with healthy amateur and professional athletes were included. Twenty studies were eventually included: 4 acute and 1 chronic in rugby union, 13 acute and 2 chronic in rugby league. Acute studies investigated task and individual constraints. Chronic studies showed that small-sided games would be an effective training method to improve physical performance. Current research in rugby football codes is heavily biased towards investigating how manipulating constraints can affect the physical characteristics of small-sided games, with limited literature investigating the effect on technical skills, and no studies investigating tactical behaviour. Future research is needed to evidence the effects of constraint manipulation on technical and tactical behaviour of rugby football players in small-sided games, in addition to physical characteristics.


Assuntos
Desempenho Atlético/fisiologia , Futebol Americano/fisiologia , Humanos
5.
J Int Soc Sports Nutr ; 18(1): 39, 2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34039357

RESUMO

BACKGROUND: Taurine has become a popular supplement among athletes attempting to improve performance. While the effectiveness of taurine as an ergogenic aid remains controversial, this paper summarizes the current evidence regarding the efficacy of taurine in aerobic and anaerobic performance, metabolic stress, muscle soreness, and recovery. METHODS: Google Scholar, Web of Science, and MedLine (PubMed) searches were conducted through September 2020. Peer-reviewed studies that investigated taurine as a single ingredient at dosages of < 1 g - 6 g, ranging from 10 to 15 min-to-2 h prior to exercise bout or chronic dose (7 days- 8 weeks) of consumption were included. Articles were excluded if taurine was not the primary or only ingredient in a supplement or food source, not published in peer-reviewed journals, if participants were older than 50 years, articles published before 1999, animal studies, or included participants with health issues. A total of 19 studies met the inclusion criteria for the review. RESULTS: Key results include improvements in the following: VO2max, time to exhaustion (TTE; n = 5 articles), 3 or 4 km time-trial (n = 2 articles), anaerobic performance (n = 7 articles), muscle damage (n = 3 articles), peak power (n = 2 articles), recovery (n = 1 article). Taurine also caused a change in metabolites: decrease in lactate, creatine kinase, phosphorus, inflammatory markers, and improved glycolytic/fat oxidation markers (n = 5 articles). Taurine dosing appears to be effective at ~ 1-3 g/day acutely across a span of 6-15 days (1-3 h before an activity) which may improve aerobic performance (TTE), anaerobic performance (strength, power), recovery (DOMS), and a decrease in metabolic markers (creatine kinase, lactate, inorganic phosphate). CONCLUSIONS: Limited and varied findings prohibit definitive conclusions regarding the efficacy of taurine on aerobic and anaerobic performance and metabolic outcomes. There are mixed findings for the effect of taurine consumption on improving recovery from training bouts and/or mitigating muscle damage. The timing of taurine ingestion as well as the type of exercise protocol performed may contribute to the effectiveness of taurine as an ergogenic aid. More investigations are needed to better understand the potential effects of taurine supplementation on aerobic and anaerobic performance, muscle damage, metabolic stress, and recovery.


Assuntos
Desempenho Atlético/fisiologia , Suplementos Nutricionais , Substâncias para Melhoria do Desempenho/administração & dosagem , Taurina/administração & dosagem , Glicemia/metabolismo , Regulação da Temperatura Corporal , Cálcio/metabolismo , Metabolismo Energético , Humanos , Inflamação/prevenção & controle , Ácido Láctico/sangue , Metabolismo dos Lipídeos , Força Muscular , Mialgia/prevenção & controle , Estresse Oxidativo , Consumo de Oxigênio , Substâncias para Melhoria do Desempenho/farmacocinética , Taurina/farmacocinética
6.
J Int Soc Sports Nutr ; 18(1): 40, 2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-34044858

RESUMO

BACKGROUND: Carbohydrate (CHO) ingestion enhances exercise performance; however, the efficacy of CHO intake on repeated bouts of exercise simulating a taekwondo tournament is unknown. Therefore, the purpose was to compare the effects of two different doses of CHO on a sports-specific kicking test during a simulated taekwondo tournament compared to placebo (PLA). METHODS: In a double-blind, randomized-placebo controlled, cross-over trial, eleven junior male professional taekwondo athletes (age: 16 ± 0.8 years, body mass: 55.3 ± 7.3 kg) ingested one of three solutions: (i) high dose (C45): 45 g of CHO (60 g∙h- 1), (ii) low dose (C22.5): 22.5 g of CHO (30 g∙h- 1; both solutions containing 2:1 glucose:fructose), or a PLA immediately following each kicking test. The kicking test was repeated 5 times, separated by 45 mins of rest, simulating a typical taekwondo competition day. Ratings of perceived exertion (RPE) and gastrointestinal discomfort (GI) scores were collected immediately after, and blood glucose before each test. RESULTS: The results revealed that C45 and C22.5 did not improve total, successful, or percentage of successful kicks compared to PLA (p > 0.05). Blood glucose was significantly higher following both CHO conditions compared with PLA across all five tests (p < 0.05). There were no differences between treatments or across tests for RPE (p > 0.05). CONCLUSION: CHO intake, independent of the dose, did not alter taekwondo kick performance during a simulated taekwondo tournament.


Assuntos
Desempenho Atlético/fisiologia , Sacarose na Dieta/administração & dosagem , Frutose/administração & dosagem , Artes Marciais/fisiologia , Adolescente , Bebidas , Glicemia/metabolismo , Índice de Massa Corporal , Comportamento Competitivo/fisiologia , Estudos Cross-Over , Sacarose na Dieta/efeitos adversos , Método Duplo-Cego , Frutose/efeitos adversos , Azia/etiologia , Humanos , Masculino , Percepção/fisiologia , Esforço Físico/fisiologia
7.
Biomed Res Int ; 2021: 5555853, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33987438

RESUMO

Objectives: Investigate the effects of integrated neuromuscular training (INT) on injury prevention and the performance of professional female badminton athletes by comparing their preintervention and postintervention tests. The study hypothesized that integrated neuromuscular training can improve the asymmetry and improve the sport performance of female badminton players. Methods: According to pretest value based on functional movement screening, 38 participants were divided into a high-risk group (HG) and a low-risk group (LG) with 22 and 16 people in each group. Two groups of athletes took part in an 8-week INT program consisting of four 90-min sessions each week. The asymmetries in movement, physical fitness, and special abilities were tested before and after the intervention. Independent sample t-test was used for the statistical analysis. Results: This research found indicated that 8 weeks of INT influenced FMS scores in both groups (HG and LG). The change of inline lunge (ES H = 0.42, ES L = 0.21) and trunk stability push-up (ES H = -0.58, ES L = -0.20) showed significant differences (P < 0.05), and the change of the FMS scores (ES H = 0.81, ES L = 0.65), deep squat (ES H = 0.6, ES L = 0.3), and rotation stability (ES H = -0.65, ES L = -0.72) showed very significant differences (P < 0.01). Compared to the pretest, most of the physical fitness parameters improved significantly in the HG and LG groups except strength index, and special abilities of the HG and LG group women badminton athletes showed a substantial increase. Conclusion: Integrated neuromuscular training can effectively improve the asymmetry of female badminton athletes' limbs, prevent sports injury, and improve the athlete's performance ability. However, athletes in different risk groups have certain differences in the degree of improvement in their motor skills.


Assuntos
Traumatismos em Atletas/prevenção & controle , Desempenho Atlético/fisiologia , Condicionamento Físico Humano/métodos , Esportes com Raquete/fisiologia , Adolescente , Atletas , Teste de Esforço , Feminino , Humanos
8.
J Int Soc Sports Nutr ; 18(1): 36, 2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-34001168

RESUMO

BACKGROUND: Elite athletes may suffer from impaired immune function and gastro-intestinal (GI) symptoms, which may affect their health and may impede their performance. These symptoms may be reduced by multi-strain probiotic supplementation. Therefore, the aim of the current study is to examine the effects of probiotic supplementation on aerobic fitness characteristics, inflammatory markers and incidence and severity of GI symptoms in elite cyclists. METHODS: Twenty-seven male cyclists, ranked elite or category 1 level competitions, were randomly assigned to a multi-strain probiotic-supplemented group (E, n = 11) or placebo group (C, n = 16). All participants visited the laboratory at the beginning of the study and following 90 d of supplementation/placebo. Prior to testing, all participants completed a GI symptoms questionnaire and underwent physical and medical examination, and anthropometric measurements. Venous blood was drawn for inflammatory markers analysis. The cyclists then underwent maximal oxygen consumption (VO2max) test and time-to-fatigue (TTF) test at 85 % of maximal power, 3 h following the VO2max test. All testing procedures were repeated after 90 d of probiotic / placebo treatment (double blind design). RESULTS: Lower incidence of nausea, belching, and vomiting (P < 0.05) at rest, and decreased incidence of GI symptoms during training were found in E group vs. C Group, respectively (∆GI -0.27 ± 0.47 % vs. 0.08 ± 0.29 %, P = 0.03), no significant changes were observed in the incidence of total overall GI symptoms (∆GI -5.6 ± 14.7 % vs. 2.6 ± 11.6 %, P = 0.602) Mean rate of perceived exertion (RPE) values during the TTF were lower in E group (∆RPE: -0.3 ± 0.9 vs. 0.8 ± 1.5, P = 0.04). No significant changes were measured between and within groups in VO2max and TTF values, mean levels of C-reactive protein (CRP), IL-6-and tumor necrosis factor alpha (TNFα) values following treatment. CONCLUSIONS: Probiotics supplementation may have beneficial effects on GI symptoms in elite cyclists. Future studies, using higher doses and during different training seasons, might help understanding the effects of probiotic supplementation on elite athletes' health and performance. TRIAL REGISTRATION: NIH clinicaltrial.gov #NCT02756221 Registered 25 April 2016.


Assuntos
Desempenho Atlético/fisiologia , Ciclismo/fisiologia , Suplementos Nutricionais , Gastroenteropatias/prevenção & controle , Inflamação/prevenção & controle , Probióticos/administração & dosagem , Adulto , Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Método Duplo-Cego , Gastroenteropatias/fisiopatologia , Humanos , Inflamação/fisiopatologia , Interleucina-6/sangue , Masculino , Fadiga Muscular , Consumo de Oxigênio , Condicionamento Físico Humano/fisiologia , Fator de Necrose Tumoral alfa/sangue , Adulto Jovem
9.
Nutrients ; 13(4)2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33918568

RESUMO

Field-based team sports present large energetic demands given their intermittent high-intensity nature. Current evidence suggests that the dietary intake of female athletes may be insufficient to meet such demands, resulting in negative consequences for athletic performance and health. The primary aim of this review was to therefore assess the adequacy of dietary intake of female field-based team sport athletes when compared to dietary recommendations. A systematic search of databases, including PubMed, Web of Science, SPORTDiscus, and OpenGrey, was performed from the earliest record available until July 2020, obtaining an initial total of 2588 articles. To be included within the final review, articles were required to provide a quantitative assessment of baseline dietary intake specific to the target population. A total of 20 studies (n = 462) met the full eligibility criteria. A majority reported that the dietary intake of female field-based team sport athletes was insufficient in overall energy (2064 ± 309 kcal·day-1), carbohydrate (4.3 ± 1.2 g·kg·day-1), and iron intake (13.6 ± 6.2 mg·day-1) when compared to recommendations. Future research is required to establish why female team sport athletes consistently demonstrate deficient dietary practices, and to explore the potential negative consequences of this.


Assuntos
Atletas , Desempenho Atlético/fisiologia , Ingestão de Alimentos , Necessidades Nutricionais/fisiologia , Esportes de Equipe , Adolescente , Adulto , Ingestão de Energia , Metabolismo Energético , Feminino , Humanos , Nutrientes
10.
Med Sci Sports Exerc ; 53(5): 883-887, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33844668

RESUMO

It is clear, based on a deep scientific literature base, that genetic and genomic factors play significant roles in determining a wide range of sport and exercise characteristics including exercise endurance capacity, strength, daily physical activity levels, and trainability of both endurance and strength. Although the research field of exercise systems genetics has rapidly expanded over the past two decades, many researchers publishing in this field are not extensively trained in molecular biology or genomics techniques, sometimes creating gaps in generating high-quality and cutting-edge research for publication. As current or former Associate Editors for Medicine and Science in Sports and Exercise that have handled the majority of exercise genetics articles for Medicine and Science in Sports and Exercise in the past 15 yr, we have observed a large number of scientific manuscripts submitted for publication review that have exhibited significant flaws preventing their publication; flaws that often directly stem from a lack of knowledge regarding the "state-of-the-art" methods and accepted literature base that is rapidly changing as the field evolves. The purpose of this commentary is to provide researchers-especially those coming from a nongenetics background attempting to publish in the exercise system genetics area-with recommendations regarding best-practice research standards and data analysis in the field of exercise systems genetics, to strengthen the overall literature in this important and evolving field of research.


Assuntos
Exercício Físico , Fenômenos Fisiológicos/genética , Polimorfismo de Nucleotídeo Único/genética , Editoração/normas , Pesquisa/normas , Desempenho Atlético/fisiologia , Análise de Dados , Estudo de Associação Genômica Ampla/normas , Genótipo , Humanos , Força Muscular/genética , Fenótipo , Condicionamento Físico Humano , Resistência Física/genética , Controle de Qualidade , Reprodutibilidade dos Testes , Projetos de Pesquisa/normas , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Tamanho da Amostra , Esportes/fisiologia
11.
Scand J Med Sci Sports ; 31(8): 1621-1635, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33829679

RESUMO

This study aimed to compare the effects of three resistance training (RT) programs differing in the magnitude of velocity loss (VL) allowed in each exercise set: 10%, 30%, or 45% on changes in strength, vertical jump, sprint performance, and EMG variables. Thirty-three young men were randomly assigned into three experimental groups (VL10%, VL30%, and VL45%; n = 11 each) that performed a velocity-based RT program for 8 weeks using only the full squat exercise (SQ). Training load (55-70% 1RM), frequency (2 sessions/week), number of sets (3), and inter-set recovery (4 min) were identical for all groups. Running sprint (20 m), countermovement jump (CMJ), 1RM, muscle endurance, and EMG during SQ were assessed pre- and post-training. All groups showed significant (VL10%: 6.4-58.6%; VL30%: 4.5-66.2%; VL45%: 1.8-52.1%; p < 0.05-0.001) improvements in muscle strength and muscle endurance. However, a significant group × time interaction (p < 0.05) was observed in CMJ, with VL10% showing greater increments (11.9%) than VL30% and VL45%. In addition, VL10% resulted in greater percent change in sprint performance than the other two groups (VL10%: -2.4%; VL30%: -1.8%; and VL45%: -0.5%). No significant changes in EMG variables were observed for any group. RT with loads of 55-70% 1RM characterized by a low-velocity loss (VL10%) provides a very effective and efficient training stimulus since it yields similar strength gains and greater improvements in sports-related neuromuscular performance (jump and sprint) compared to training with higher velocity losses (VL30%, VL45%). These findings indicate that the magnitude of VL reached in each exercise set considerably influences the observed training adaptations.


Assuntos
Desempenho Atlético/fisiologia , Força Muscular/fisiologia , Treinamento de Força/métodos , Adulto , Teste de Esforço , Humanos , Estudos Longitudinais , Masculino , Adulto Jovem
12.
Scand J Med Sci Sports ; 31(8): 1647-1656, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33844358

RESUMO

We designed and tested a protocol for measuring the performance of individuals in small-sided soccer games. We tested our protocol on three different groups of youth players from elite Brazilian football academies. Players in each group played a series of 3v3 games, in which individuals were randomly assigned into new teams and against new opponents for each game. We calculated each individual's average individual goals scored, goals scored by teammates, goals conceded, and net team goals per game. Our protocol was consistent across days and repeatable across groups, with intraclass correlation coefficients (ICCs) of 0.57-0.69 for average net goals per game across testing days. Players could achieve high success by scoring goals or ensuring their team concede few goals. We also calculated the first and second dimension of a principal component analysis based on each player's number of goals scored, goals scored by teammates, and number of goals conceded per game. Players that were overall high performers had higher PC1 scores, while PC2 scores represented the type of contribution made by a player to overall performance. Positive PC2 values were indicative of high number of individual goals while negative values were associated with more goals from teammates and fewer conceded goals. Our design allows coaches and scouts to easily collect a robust metric of individual performance using randomly designed, small-sided games. We also provide simulations that allow one to apply our methodology for individual talent identification to other small-sided games in any team sport.


Assuntos
Atletas/estatística & dados numéricos , Desempenho Atlético/fisiologia , Desempenho Atlético/estatística & dados numéricos , Futebol/fisiologia , Futebol/estatística & dados numéricos , Aptidão , Criança , Teste de Esforço , Humanos , Reprodutibilidade dos Testes
13.
Nutrients ; 13(4)2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33919779

RESUMO

Nutritional intake can influence exercise metabolism and performance, but there is a lack of research comparing protein-rich pre-exercise meals with endurance exercise performed both in the fasted state and following a carbohydrate-rich breakfast. The purpose of this study was to determine the effects of three pre-exercise nutrition strategies on metabolism and exercise capacity during cycling. On three occasions, seventeen trained male cyclists (VO2peak 62.2 ± 5.8 mL·kg-1·min-1, 31.2 ± 12.4 years, 74.8 ± 9.6 kg) performed twenty minutes of submaximal cycling (4 × 5 min stages at 60%, 80%, and 100% of ventilatory threshold (VT), and 20% of the difference between power at the VT and peak power), followed by 3 × 3 min intervals at 80% peak aerobic power and 3 × 3 min intervals at maximal effort, 30 min after consuming a carbohydrate-rich meal (CARB; 1 g/kg CHO), a protein-rich meal (PROTEIN; 0.45 g/kg protein + 0.24 g/kg fat), or water (FASTED), in a randomized and counter-balanced order. Fat oxidation was lower for CARB compared with FASTED at and below the VT, and compared with PROTEIN at 60% VT. There were no differences between trials for average power during high-intensity intervals (367 ± 51 W, p = 0.516). Oxidative stress (F2-Isoprostanes), perceived exertion, and hunger were not different between trials. Overall, exercising in the overnight-fasted state increased fat oxidation during submaximal exercise compared with exercise following a CHO-rich breakfast, and pre-exercise protein ingestion allowed similarly high levels of fat oxidation. There were no differences in perceived exertion, hunger, or performance, and we provide novel data showing no influence of pre-exercise nutrition ingestion on exercise-induced oxidative stress.


Assuntos
Ciclismo/fisiologia , Jejum/fisiologia , Refeições/fisiologia , Estresse Oxidativo/fisiologia , Adolescente , Adulto , Atletas , Desempenho Atlético/fisiologia , Carboidratos da Dieta/administração & dosagem , Proteínas na Dieta/administração & dosagem , Humanos , Fome/fisiologia , Metabolismo dos Lipídeos/fisiologia , Masculino , Oxirredução , Resistência Física/fisiologia , Esforço Físico/fisiologia , Adulto Jovem
14.
Nutrients ; 13(4)2021 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-33924645

RESUMO

Purpose: A growing number of studies indicate the importance of vitamin D supplementation for sports performance. However, the effects of a single high-dose vitamin D supplementation on ultramarathon-induced inflammation have not been investigated. We here analyzed the effect of a single high-dose vitamin D supplementation on the inflammatory marker levels in ultramarathon runners after an ultramarathon run (maximal run 240 km). Methods: In the study, 35 runners (amateurs) were assigned into two groups: single high-dose vitamin D supplementation group, administered vitamin D (150,000 IU) in vegetable oil 24 h before the start of the run (n = 16); and placebo group (n = 19). Blood was collected for analysis 24 h before, immediately after, and 24 h after the run. Results: Serum 25(OH)D levels were significantly increased after the ultramarathon in both groups. The increase was greater in the vitamin D group than in the control group. Based on post-hoc and other analyses, the increase in interleukin 6 and 10, and resistin levels immediately after the run was significantly higher in runners in the control group than that in those in the supplementation group. Leptin, oncostatin M, and metalloproteinase tissue inhibitor levels were significantly decreased in both groups after the run, regardless of the supplementation. Conclusions: Ultramarathon significantly increases the serum 25(OH)D levels. Attenuation of changes in interleukin levels upon vitamin D supplementation confirmed that vitamin D has anti-inflammatory effect on exercise-induced inflammation.


Assuntos
Desempenho Atlético/fisiologia , Suplementos Nutricionais , Inflamação/dietoterapia , Corrida de Maratona/fisiologia , Vitamina D/administração & dosagem , Adaptação Fisiológica/imunologia , Adulto , Biomarcadores/sangue , Método Duplo-Cego , Humanos , Inflamação/diagnóstico , Inflamação/imunologia , Masculino , Pessoa de Meia-Idade , Vitamina D/sangue , Vitamina D/metabolismo
15.
Nutrients ; 13(5)2021 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-33922108

RESUMO

Regular physical exercise and a healthy diet are major determinants of a healthy lifespan. Although aging is associated with declining endurance performance and muscle function, these components can favorably be modified by regular physical activity and especially by exercise training at all ages in both sexes. In addition, age-related changes in body composition and metabolism, which affect even highly trained masters athletes, can in part be compensated for by higher exercise metabolic efficiency in active individuals. Accordingly, masters athletes are often considered as a role model for healthy aging and their physical capacities are an impressive example of what is possible in aging individuals. In the present review, we first discuss physiological changes, performance and trainability of older athletes with a focus on sex differences. Second, we describe the most important hormonal alterations occurring during aging pertaining regulation of appetite, glucose homeostasis and energy expenditure and the modulatory role of exercise training. The third part highlights nutritional aspects that may support health and physical performance for older athletes. Key nutrition-related concerns include the need for adequate energy and protein intake for preventing low bone and muscle mass and a higher demand for specific nutrients (e.g., vitamin D and probiotics) that may reduce the infection burden in masters athletes. Fourth, we present important research findings on the association between exercise, nutrition and the microbiota, which represents a rapidly developing field in sports nutrition.


Assuntos
Envelhecimento/fisiologia , Atletas , Fenômenos Fisiológicos da Nutrição , Caracteres Sexuais , Desempenho Atlético/fisiologia , Feminino , Humanos , Masculino , Publicações
16.
Res Sports Med ; 29(4): 386-394, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33870819

RESUMO

High-speed running density (HSRd) is the ratio of high-speed efforts and distance covered. This study aimed to evaluate differences in HSRd between training, games, and among positions in collegiate women's lacrosse, and correlate HSRd with other training metrics. Data were collected during a collegiate training year (practices n = 162, games n = 14) through players (n = 25) wearing microtechnology. HSRd differed between training sessions and games (p < .001, d = .281) and by position (p < .001, d = .005-.712). Games (14.7 ± 13.8%) had a higher HSRd than training sessions (13.1 ± 13.7%), and goalies had higher HSRd during games than the other positions. HSRd was moderately inversely correlated (p < .001) with max speed (r = -.395-.543) and had low inverse correlations (p < .001) with distance (r = -.134-.225), accelerations (r = -217-.233), and decelerations (r = -.195-.268). Training did not mimic the HSRd of games. Defenders and goalies perform intense reactionary movements to make a defensive play, resulting in higher HSRd.


Assuntos
Desempenho Atlético/fisiologia , Esportes com Raquete/fisiologia , Corrida/fisiologia , Adolescente , Adulto , Feminino , Sistemas de Informação Geográfica , Humanos , Estudos Prospectivos , Universidades , Adulto Jovem
17.
Nutrients ; 13(5)2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33919043

RESUMO

BACKGROUND: Previous research has reported that elite Gaelic football players' carbohydrate (CHO) intakes are sub-optimal, especially, in the lead up to competitive matches. Despite clear decrements in running performance across elite Gaelic football matches, there are no studies that have investigated nutrition interventions on match-related Gaelic football performance. The aim of this study was to determine whether a higher-CHO diet in line with sports nutrition guidelines can improve Gaelic football-related performance compared to lower CHO intakes previously observed in Gaelic footballers. METHODS: Twelve Gaelic football players completed a Gaelic football simulation protocol (GFSP) on two occasions after consuming a high-CHO diet (7 g·kg-1) (HCHO) or an energy-matched lower-CHO diet (3.5 g·kg-1) (L-CHO) for 48 h. Movement demands and heart rate were measured using portable global positioning systems devices. Countermovement jump height (CMJ) and repeated-sprint ability (RSA) were measured throughout each trial. Expired respiratory gases were collected throughout the trial using a portable gas analyser. Blood samples were taken at rest, half-time, and post-simulation. RESULTS: There was no significant difference in total distance (p = 0.811; η2 = 0.005) or high-speed running distance (HSRD) covered between both trials. However, in the second half of the HCHO trial, HSRD was significantly greater compared to the second half of the LCHO trial (p = 0.015). Sprint distance covered during GFSP was significantly greater in HCHO (8.1 ± 3.5 m·min-1) compared with LCHO (6.4 ± 3.2 m·min-1) (p = 0.011; η2 = 0.445). RSA performance (p < 0.0001; η2 = 0.735) and lower body power (CMJ) (p < 0.0001; η2 = 0.683) were significantly greater during the HCHO trial compared to LCHO. Overall CHO oxidation rates were significantly greater under HCHO conditions compared to LCHO (3.3 ± 0.5 vs. 2.7 ± 0.6 g·min-1) (p < 0.001; η2 = 0.798). Blood lactate concentrations were significantly higher during HCHO trial versus LCHO (p = 0.026; η2 = 0.375). There were no significant differences in plasma glucose, non-esterified fatty acids (NEFAs), and glycerol concentration between trials. In both trials, all blood metabolites were significantly elevated at half-time and post-trial compared to pre-trial. CONCLUSION: These findings indicate that a higher-CHO diet can reduce declines in physical performance during simulated Gaelic football match play.


Assuntos
Desempenho Atlético/fisiologia , Carboidratos da Dieta/farmacologia , Comportamento Alimentar/efeitos dos fármacos , Futebol Americano/fisiologia , Corrida/fisiologia , Glicemia/metabolismo , Ingestão de Energia , Frequência Cardíaca/fisiologia , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Metaboloma , Oxirredução , Respiração/efeitos dos fármacos , Especificidade por Substrato/efeitos dos fármacos , Adulto Jovem
18.
Nutrients ; 13(4)2021 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-33920560

RESUMO

BACKGROUND: Athletes maintain a balance between stress and recovery and adopt recovery modalities that manage fatigue and enhance recovery and performance. Optimal TST is subject to individual variance. However, 7-9 h sleep is recommended for adults, while elite athletes may require more quality sleep than non-athletes. METHODS: A total of 338 (elite n = 115, 74 males and 41 females, aged 23.44 ± 4.91 years; and sub-elite n = 223, 129 males and 94 females aged 25.71 ± 6.27) athletes were recruited from a variety of team and individual sports to complete a battery of previously validated and reliable widely used questionnaires assessing sleep, recovery and nutritional practices. RESULTS: Poor sleep was reported by both the elite and sub-elite athlete groups (i.e., global PSQI score ≥5-elite 64% [n = 74]; sub-elite 65% [n = 146]) and there was a significant difference in sport-specific recovery practices (3.22 ± 0.90 vs. 2.91 ± 0.90; p < 0.001). Relatively high levels of fatigue (2.52 ± 1.32), stress (1.7 ± 1.31) and pain (50%, n = 169) were reported in both groups. A range of supplements were used regularly by athletes in both groups; indeed, whey (elite n = 22 and sub-elite n = 48) was the most commonly used recovery supplement in both groups. Higher alcohol consumption was observed in the sub-elite athletes (12%, n = 26) and they tended to consume more units of alcohol per drinking bout. CONCLUSION: There is a need for athletes to receive individualised support and education regarding their sleep and recovery practices.


Assuntos
Atletas/estatística & dados numéricos , Desempenho Atlético/estatística & dados numéricos , Suplementos Nutricionais/estatística & dados numéricos , Sono , Esportes/estatística & dados numéricos , Adulto , Consumo de Bebidas Alcoólicas , Desempenho Atlético/fisiologia , Feminino , Humanos , Irlanda , Masculino , Recuperação de Função Fisiológica/fisiologia , Esportes/fisiologia , Fenômenos Fisiológicos da Nutrição Esportiva , Inquéritos e Questionários , Reino Unido , Adulto Jovem
19.
Nutrients ; 13(3)2021 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-33800770

RESUMO

This single-arm interventional study examined the effect of a 4-week ketogenic diet (KD) on aerobic capacity and discipline-specific performance in female (n = 11) and male (n = 11) CrossFit-trained athletes. The participants performed incremental cycling (ICT) and Fight Gone Bad (FGB) tests after consuming a customary diet and a KD. Pre- and post-ICT exercise blood samples were also analysed. Consuming a KD had a slight impact on aerobic capacity and no relevant effect on CrossFit-specific performance. In females, consuming a KD led to an 10.4% decrease in peak oxygen uptake during the ICT (p = 0.027) and resulted in certain alterations in haematological parameters (haemoglobin (HGB), mean corpuscular HGB, and mean corpuscular HGB concentration). Furthermore, in males, alanine aminotransferase activity increased with a simultaneous improvement in the post-ICT blood acid-base balance after consuming a KD. The pre-exercise bilirubin concentration was also elevated in the entire group after consuming a KD. In conclusion, female CrossFit-trained athletes seem to be prone to aerobic performance decrements and increased risk of developing haematological disturbances when consuming a KD. In males who consumed a KD, there was an undesirable alanine aminotransferase elevation and a small tendency towards improved acid-base status. Moreover, consuming a KD had no effect on discipline-specific performance in CrossFit-trained athletes.


Assuntos
Desempenho Atlético/fisiologia , Ciclismo/fisiologia , Dieta Cetogênica/efeitos adversos , Treinamento Intervalado de Alta Intensidade , Equilíbrio Ácido-Base , Adolescente , Adulto , Alanina Transaminase/sangue , Bilirrubina/sangue , Índices de Eritrócitos/fisiologia , Feminino , Hemoglobinas/metabolismo , Humanos , Masculino , Consumo de Oxigênio , Fatores Sexuais , Adulto Jovem
20.
Medicine (Baltimore) ; 100(14): e25423, 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33832142

RESUMO

BACKGROUND: In recent years, the functional movement screen (FMS) and FMS training have attracted attention as a means of preventing injury, but no studies have examined the effect of such training in high-school baseball players. The aim of this study was to clarify the effect of FMS training on FMS score, physical function and baseball performance in high-school baseball players. METHODS: Subjects in this randomized controlled clinical trial were high-school male baseball players assigned to either an FMS training group (intervention group) or a control group. The intervention group performed FMS training 4 times per week for 12 weeks. FMS ability, physical function, and baseball performance were measured prior to the intervention, 8, 12, and 24 weeks after the intervention in the subjects' school environment. RESULTS: A total of 71 baseball players aged 15 to 17 years were recruited and assigned to either an intervention group (n = 37) or control group (n = 34). There was no significant difference in the characteristics of participants between the 2 groups. Most FMS scores improved to 12 weeks after continued training. In the intervention group compared with the control group, deep squat, hurdle step, inline lunge, active straight leg raise, trunk stability push-up and rotary stability FMS score, total FMS score and eyes closed single leg stance time significantly increased after 8 weeks of training. While hurdle step, inline lunge, active straight leg raise, trunk stability push-up, total FMS score, and eyes closed single leg stance time significantly increased, pitching ball speed significantly decreased at the end of the 12 week training period. Eyes closed single leg stance time and feeling of fatigue significantly improved 12 weeks after training. The number of subjects who scored less than 14 for the total FMS score in the intervention group compared with control group were significantly less after 8 and 12 weeks of FMS training. CONCLUSION: FMS training for 8 weeks contributes to improving FMS scores for high-school baseball players, but FMS scores go down if FMS training is not continued. TRIAL REGISTRATION: University Hospital Medical Information Network Center, Tokyo, Japan: UMIN000027553. Registered on May 30, 2017.


Assuntos
Traumatismos em Atletas/prevenção & controle , Desempenho Atlético/fisiologia , Beisebol/fisiologia , Movimento/fisiologia , Condicionamento Físico Humano/métodos , Adolescente , Beisebol/lesões , Humanos , Masculino , Avaliação de Resultados em Cuidados de Saúde
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