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1.
J Int Soc Sports Nutr ; 16(1): 34, 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31409363

RESUMO

BACKGROUND: We previously reported that consuming a food bar (FB) containing whey protein and the plant fiber isomalto-oligosaccharides [IMO] had a lower glycemic (GI) but similar insulinemic response as a high GI carbohydrate. Therefore, we hypothesized that ingestion of this FB before, during, and following intense exercise would better maintain glucose homeostasis and performance while hastening recovery in comparison to the common practice of ingesting carbohydrate alone. METHODS: Twelve resistance-trained males participated in an open label, randomized, counterbalanced, crossover trial with a 7-d washout period. Participants consumed a carbohydrate matched dextrose comparitor (CHO) or a FB containing 20 g of whey, 25 g of IMO, and 7 g of fat 30-min before, mid-way, and following intense exercise. Participants performed 11 resistance-exercises (3 sets of 10 repetitions at 70% of 1RM) followed by agility and sprint conditioning drills for time. Participants donated blood to assess catabolic and inflammatory markers, performed isokinetic strength tests, and rated perceptions of muscle soreness, hypoglycemia before, and following exercise and after 48 h of recovery. Data were analyzed using general linear models (GLM) for repeated measures and mean changes from baseline with 95% confidence intervals (CI) with a one-way analysis of variance. Data are reported as mean change from baseline with 95% CI. RESULTS: GLM analysis demonstrated that blood glucose was significantly higher 30-min post-ingestion for CHO (3.1 [2.0, 4.3 mmol/L,] and FB (0.8 [0.2, 1.5, mmol/L, p = 0.001) while the post-exercise ratio of insulin to glucose was greater with FB (CHO 0.04 [0.00, 0.08], FB 0.11 [0.07, 0.15], p = 0.013, η2 = 0.25). GLM analysis revealed no significant interaction effects between treatments in lifting volume of each resistance-exercise or total lifting volume. However, analysis of mean changes from baseline with 95% CI's revealed that leg press lifting volume (CHO -130.79 [- 235.02, - 26.55]; FB -7.94 [- 112.17, 96.30] kg, p = 0.09, η2 = 0.12) and total lifting volume (CHO -198.26 [- 320.1, - 76.4], FB -81.7 [- 203.6, 40.1] kg, p = 0.175, η2 = 0.08) from set 1 to 3 was significantly reduced for CHO, but not for the FB. No significant interaction effects were observed in ratings of muscle soreness. However, mean change analysis revealed that ratings of soreness of the distal vastus medialis significantly increased from baseline with CHO while being unchanged with FB (CHO 1.88 [0.60, 3.17]; FB 0.29 [- 0.99, 1.57] cm, p = 0.083, η2 = 0.13). No significant GLM interaction or mean change analysis effects were seen between treatments in sprint performance, isokinetic strength, markers of catabolism, stress and sex hormones, or inflammatory markers. CONCLUSION: Pilot study results provide some evidence that ingestion of this FB can positively affect glucose homeostasis, help maintain workout performance, and lessen perceptions of muscle soreness. TRIAL REGISTRATION: clinicaltrials.gov, # NCT03704337 . Retrospectively registered 12, July 2018.


Assuntos
Carboidratos da Dieta/administração & dosagem , Suplementos Nutricionais , Treinamento de Força , Proteínas do Soro do Leite/administração & dosagem , Glicemia , Estudos Cross-Over , Ingestão de Alimentos , Teste de Esforço , Humanos , Insulina/sangue , Contração Isométrica , Masculino , Mialgia , Oligossacarídeos/administração & dosagem , Projetos Piloto , Fenômenos Fisiológicos da Nutrição Esportiva , Adulto Jovem
2.
Nutrients ; 10(8)2018 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-30103509

RESUMO

Resistance training and maintenance of a higher protein diet have been recommended to help older individuals maintain muscle mass. This study examined whether adherence to a higher protein diet while participating in a resistance-based exercise program promoted more favorable changes in body composition, markers of health, and/or functional capacity in older females in comparison to following a traditional higher carbohydrate diet or exercise training alone with no diet intervention. In total, 54 overweight and obese females (65.9 ± 4.7 years; 78.7 ± 11 kg, 30.5 ± 4.1 kg/m², 43.5 ± 3.6% fat) were randomly assigned to an exercise-only group (E), an exercise plus hypo-energetic higher carbohydrate (HC) diet, or a higher protein diet (HP) diet. Participants followed their respective diet plans and performed a supervised 30-min circuit-style resistance exercise program 3 d/wk. Participants were tested at 0, 10, and 14 weeks. Data were analyzed using univariate, multivariate, and repeated measures general linear model (GLM) statistics as well as one-way analysis of variance (ANOVA) of changes from baseline with [95% confidence intervals]. Results revealed that after 14 weeks, participants in the HP group experienced significantly greater reductions in weight (E -1.3 ± 2.3, [-2.4, -0.2]; HC -3.0 ± 3.1 [-4.5, -1.5]; HP -4.8 ± 3.2, [-6.4, -3.1]%, p = 0.003), fat mass (E -2.7 ± 3.8, [-4.6, -0.9]; HC -5.9 ± 4.2 [-8.0, -3.9]; HP -10.2 ± 5.8 [-13.2, ⁻7.2%], p < 0.001), and body fat percentage (E -2.0 ± 3.5 [-3.7, -0.3]; HC -4.3 ± 3.2 [-5.9, -2.8]; HP -6.3 ± 3.5 [-8.1, -4.5] %, p = 0.002) with no significant reductions in fat-free mass or resting energy expenditure over time or among groups. Significant differences were observed in leptin (E -1.8 ± 34 [-18, 14]; HC 43.8 ± 55 [CI 16, 71]; HP -26.5 ± 70 [-63, -9.6] ng/mL, p = 0.001) and adiponectin (E 43.1 ± 76.2 [6.3, 79.8]; HC -27.9 ± 33.4 [-44.5, -11.3]; HP 52.3 ± 79 [11.9, 92.8] µg/mL, p = 0.001). All groups experienced significant improvements in muscular strength, muscular endurance, aerobic capacity, markers of balance and functional capacity, and several markers of health. These findings indicate that a higher protein diet while participating in a resistance-based exercise program promoted more favorable changes in body composition compared to a higher carbohydrate diet in older females.


Assuntos
Dieta Rica em Proteínas , Tolerância ao Exercício , Obesidade/terapia , Cooperação do Paciente , Treinamento de Força , Perda de Peso , Fatores Etários , Idoso , Biomarcadores/sangue , Composição Corporal , Feminino , Nível de Saúde , Humanos , Pessoa de Meia-Idade , Força Muscular , Obesidade/sangue , Obesidade/diagnóstico , Obesidade/fisiopatologia , Estudos Prospectivos , Fatores Sexuais , Texas , Fatores de Tempo , Resultado do Tratamento
3.
J Int Soc Sports Nutr ; 15(1): 38, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30068354

RESUMO

BACKGROUND: Sports nutrition is a constantly evolving field with hundreds of research papers published annually. In the year 2017 alone, 2082 articles were published under the key words 'sport nutrition'. Consequently, staying current with the relevant literature is often difficult. METHODS: This paper is an ongoing update of the sports nutrition review article originally published as the lead paper to launch the Journal of the International Society of Sports Nutrition in 2004 and updated in 2010. It presents a well-referenced overview of the current state of the science related to optimization of training and performance enhancement through exercise training and nutrition. Notably, due to the accelerated pace and size at which the literature base in this research area grows, the topics discussed will focus on muscle hypertrophy and performance enhancement. As such, this paper provides an overview of: 1.) How ergogenic aids and dietary supplements are defined in terms of governmental regulation and oversight; 2.) How dietary supplements are legally regulated in the United States; 3.) How to evaluate the scientific merit of nutritional supplements; 4.) General nutritional strategies to optimize performance and enhance recovery; and, 5.) An overview of our current understanding of nutritional approaches to augment skeletal muscle hypertrophy and the potential ergogenic value of various dietary and supplemental approaches. CONCLUSIONS: This updated review is to provide ISSN members and individuals interested in sports nutrition with information that can be implemented in educational, research or practical settings and serve as a foundational basis for determining the efficacy and safety of many common sport nutrition products and their ingredients.


Assuntos
Suplementos Nutricionais/normas , Regulamentação Governamental , Substâncias para Melhoria do Desempenho/normas , Atletas , Dieta , Exercício Físico , Humanos , Hipertrofia , Músculo Esquelético/crescimento & desenvolvimento , Necessidades Nutricionais , Sociedades , Ciências da Nutrição e do Esporte , Estados Unidos
4.
J Strength Cond Res ; 32(3): 736-747, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27941488

RESUMO

Cooke, MB, Nix, C, Greenwood, L, and Greenwood, M. No Differences Between Alter G-Trainer and Active and Passive Recovery Strategies on Isokinetic Strength, Systemic Oxidative Stress and Perceived Muscle Soreness After Exercise-Induced Muscle Damage. J Strength Cond Res 32(3): 736-747, 2018-The incidence of muscle injuries is prevalent in elite sport athletes and weekend warriors and strategies that safely and effectively hasten recovery are highly desirable. The purpose of this study was to examine the differences between 3 recovery methods after eliciting muscle damage in recreationally active men relative to maximal isokinetic contractions, perceived muscle soreness, and psychological mood states. Twenty-five recreationally active men (22.15 ± 3.53 years, 75.75 ± 11.91 kg, 180.52 ± 7.3 cm) were randomly matched by V[Combining Dot Above]O2 peak (53.86 ± 6.65 ml·kg·min) and assigned to one of 3 recovery methods: anti-gravity treadmill (G-Trainer) (N = 8), conventional treadmill (N = 8) or static stretching (N = 9). Recovery methods were performed 30 minutes, 24, 48, and 72 hours after a 45-minute downhill run. Following eccentrically biased running, no significant differences were noted in isokinetic knee flexion and extension peak torque, systemic markers of muscle damage, oxidative stress and lipid peroxidation such as serum creatine kinase (CK), superoxide dismutase (SOD), and malondialdehyde (MDA), respectively, and subjective ratings of perceived muscle soreness between recovery methods. The G-Trainer group did however display a higher mood state as indicated by the Profile of Mood State global scores at 24 hours postexercise when compared to the conventional treadmill recovery group (p = 0.035). The improved mood state after the use of the anti-gravity treadmill may provide clinical relevance to other populations.


Assuntos
Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Mialgia/fisiopatologia , Estresse Oxidativo/fisiologia , Recuperação de Função Fisiológica/fisiologia , Adulto , Creatina Quinase/sangue , Exercício Físico/fisiologia , Teste de Esforço , Humanos , Peroxidação de Lipídeos/fisiologia , Masculino , Percepção , Amplitude de Movimento Articular , Corrida/fisiologia , Torque , Adulto Jovem
5.
Nutrients ; 9(12)2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-29244743

RESUMO

In a double-blind, crossover, randomized and placebo-controlled trial; 28 men and women ingested a placebo (PLA), 3 g of creatine nitrate (CNL), and 6 g of creatine nitrate (CNH) for 6 days. Participants repeated the experiment with the alternate supplements after a 7-day washout. Hemodynamic responses to a postural challenge, fasting blood samples, and bench press, leg press, and cycling time trial performance and recovery were assessed. Data were analyzed by univariate, multivariate, and repeated measures general linear models (GLM). No significant differences were found among treatments for hemodynamic responses, clinical blood markers or self-reported side effects. After 5 days of supplementation, one repetition maximum (1RM) bench press improved significantly for CNH (mean change, 95% CI; 6.1 [3.5, 8.7] kg) but not PLA (0.7 [-1.6, 3.0] kg or CNL (2.0 [-0.9, 4.9] kg, CNH, p = 0.01). CNH participants also tended to experience an attenuated loss in 1RM strength during the recovery performance tests following supplementation on day 5 (PLA: -9.3 [-13.5, -5.0], CNL: -9.3 [-13.5, -5.1], CNH: -3.9 [-6.6, -1.2] kg, p = 0.07). After 5 days, pre-supplementation 1RM leg press values increased significantly, only with CNH (24.7 [8.8, 40.6] kg, but not PLA (13.9 [-15.7, 43.5] or CNL (14.6 [-0.5, 29.7]). Further, post-supplementation 1RM leg press recovery did not decrease significantly for CNH (-13.3 [-31.9, 5.3], but did for PLA (-30.5 [-53.4, -7.7] and CNL (-29.0 [-49.5, -8.4]). CNL treatment promoted an increase in bench press repetitions at 70% of 1RM during recovery on day 5 (PLA: 0.4 [-0.8, 1.6], CNL: 0.9 [0.35, 1.5], CNH: 0.5 [-0.2, 0.3], p = 0.56), greater leg press endurance prior to supplementation on day 5 (PLA: -0.2 [-1.6, 1.2], CNL: 0.9 [0.2, 1.6], CNH: 0.2 [-0.5, 0.9], p = 0.25) and greater leg press endurance during recovery on day 5 (PLA: -0.03 [-1.2, 1.1], CNL: 1.1 [0.3, 1.9], CNH: 0.4 [-0.4, 1.2], p = 0.23). Cycling time trial performance (4 km) was not affected. Results indicate that creatine nitrate supplementation, up to a 6 g dose, for 6 days, appears to be safe and provide some ergogenic benefit.


Assuntos
Desempenho Atlético , Creatina/administração & dosagem , Suplementos Nutricionais , Nitratos/administração & dosagem , Substâncias para Melhoria do Desempenho/administração & dosagem , Adolescente , Adulto , Animais , Antropometria , Ciclismo , Composição Corporal , Creatina/sangue , Estudos Cross-Over , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Hemodinâmica , Humanos , Masculino , Força Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/fisiologia , Nitratos/sangue , Substâncias para Melhoria do Desempenho/sangue , Resistência Física , Inquéritos e Questionários , Resultado do Tratamento , Adulto Jovem
6.
J Int Soc Sports Nutr ; 14: 33, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28919842

RESUMO

The International Society of Sports Nutrition (ISSN) provides an objective and critical review regarding the timing of macronutrients in reference to healthy, exercising adults and in particular highly trained individuals on exercise performance and body composition. The following points summarize the position of the ISSN:Nutrient timing incorporates the use of methodical planning and eating of whole foods, fortified foods and dietary supplements. The timing of energy intake and the ratio of certain ingested macronutrients may enhance recovery and tissue repair, augment muscle protein synthesis (MPS), and improve mood states following high-volume or intense exercise.Endogenous glycogen stores are maximized by following a high-carbohydrate diet (8-12 g of carbohydrate/kg/day [g/kg/day]); moreover, these stores are depleted most by high volume exercise.If rapid restoration of glycogen is required (< 4 h of recovery time) then the following strategies should be considered:aggressive carbohydrate refeeding (1.2 g/kg/h) with a preference towards carbohydrate sources that have a high (> 70) glycemic indexthe addition of caffeine (3-8 mg/kg)combining carbohydrates (0.8 g/kg/h) with protein (0.2-0.4 g/kg/h) Extended (> 60 min) bouts of high intensity (> 70% VO2max) exercise challenge fuel supply and fluid regulation, thus carbohydrate should be consumed at a rate of ~30-60 g of carbohydrate/h in a 6-8% carbohydrate-electrolyte solution (6-12 fluid ounces) every 10-15 min throughout the entire exercise bout, particularly in those exercise bouts that span beyond 70 min. When carbohydrate delivery is inadequate, adding protein may help increase performance, ameliorate muscle damage, promote euglycemia and facilitate glycogen re-synthesis.Carbohydrate ingestion throughout resistance exercise (e.g., 3-6 sets of 8-12 repetition maximum [RM] using multiple exercises targeting all major muscle groups) has been shown to promote euglycemia and higher glycogen stores. Consuming carbohydrate solely or in combination with protein during resistance exercise increases muscle glycogen stores, ameliorates muscle damage, and facilitates greater acute and chronic training adaptations.Meeting the total daily intake of protein, preferably with evenly spaced protein feedings (approximately every 3 h during the day), should be viewed as a primary area of emphasis for exercising individuals.Ingestion of essential amino acids (EAA; approximately 10 g)either in free form or as part of a protein bolus of approximately 20-40 g has been shown to maximally stimulate muscle protein synthesis (MPS).Pre- and/or post-exercise nutritional interventions (carbohydrate + protein or protein alone) may operate as an effective strategy to support increases in strength and improvements in body composition. However, the size and timing of a pre-exercise meal may impact the extent to which post-exercise protein feeding is required.Post-exercise ingestion (immediately to 2-h post) of high-quality protein sources stimulates robust increases in MPS.In non-exercising scenarios, changing the frequency of meals has shown limited impact on weight loss and body composition, with stronger evidence to indicate meal frequency can favorably improve appetite and satiety. More research is needed to determine the influence of combining an exercise program with altered meal frequencies on weight loss and body composition with preliminary research indicating a potential benefit.Ingesting a 20-40 g protein dose (0.25-0.40 g/kg body mass/dose) of a high-quality source every three to 4 h appears to most favorably affect MPS rates when compared to other dietary patterns and is associated with improved body composition and performance outcomes.Consuming casein protein (~ 30-40 g) prior to sleep can acutely increase MPS and metabolic rate throughout the night without influencing lipolysis.


Assuntos
Desempenho Atlético/fisiologia , Carboidratos da Dieta/administração & dosagem , Proteínas na Dieta/administração & dosagem , Glicogênio/metabolismo , Resistência Física/fisiologia , Treinamento de Força , Ciências da Nutrição e do Esporte , Composição Corporal , Carboidratos da Dieta/metabolismo , Proteínas na Dieta/metabolismo , Metabolismo Energético , Comportamento Alimentar , Humanos , Necessidades Nutricionais , Sociedades , Fatores de Tempo
7.
J Int Soc Sports Nutr ; 14: 29, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28811750

RESUMO

BACKGROUND: The purpose was to survey dietary habits (DH) and nutrient timing (NT) practices of baseball student-athletes (mean ± SD; 20.7 ± 1.4 yr.) from three NCAA Division I institutions, and examine the effect of a sports dietitian (SD) in regard to nutrition practices. METHODS: Descriptive statistics and Pearson X2 analyses were run. Responses on 10 DH and 5 NT items differed (p ≤ 0.10) between athletes who sought dietary planning from a SD (n = 36) versus those who consulted a strength and conditioning coach (SCC, n = 42). RESULTS: In regard to DH items, the SD group found it easier to eat before activity (92% vs. 71%, p = 0.03), did not consume fast food (31% vs. 14%, p = 0.02), caffeinated beverages (57% vs. 46%, p = 0.02), or soda (56% vs. 37%, p = 0.10), prepared their own meals more often (86% vs. 73%, p = 0.07), and took daily multi-vitamins (56% vs. 32%, p = 0.02). The SCC group ate more at burger locations (21% vs. 6%, p = 0.02). In regard to NT items, the SD group ate breakfast before training/lifting sessions (67% vs. 37%, p = 0.02), and had post-workout nutrition options provided (61% vs. 27%, p = 0.01). The SCC group reported pre-competition meals of fast food (58% vs. 45%, p = 0.01), and sport coaches who were less aware of healthy food options (39% vs. 65%, p = 0.05). CONCLUSIONS: The SD is as a valuable asset to an intercollegiate athletics program. In the current study, athletes from the SD group consumed less high calorie/low nutrient dense items, ate before exercise, and consumed healthier options post-exercise. The presence of a SD was linked to provision of healthier food options during team trips. The evidence-based eating strategies and dietary plan provided by a SD may lead to improved performance and recovery.


Assuntos
Beisebol , Nutricionistas , Fenômenos Fisiológicos da Nutrição Esportiva , Adolescente , Atletas , Estudos Transversais , Dieta Saudável , Humanos , Masculino , Necessidades Nutricionais , Universidades , Adulto Jovem
8.
Nutrients ; 9(8)2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28763003

RESUMO

In a double-blind, randomized and crossover manner, 25 resistance-trained participants ingested a placebo (PLA) beverage containing 12 g of dextrose and a beverage (RTD) containing caffeine (200 mg), ß-alanine (2.1 g), arginine nitrate (1.3 g), niacin (65 mg), folic acid (325 mcg), and Vitamin B12 (45 mcg) for 7-days, separated by a 7-10-day. On day 1 and 6, participants donated a fasting blood sample and completed a side-effects questionnaire (SEQ), hemodynamic challenge test, 1-RM and muscular endurance tests (3 × 10 repetitions at 70% of 1-RM with the last set to failure on the bench press (BP) and leg press (LP)) followed by ingesting the assigned beverage. After 15 min, participants repeated the hemodynamic test, 1-RM tests, and performed a repetition to fatigue (RtF) test at 70% of 1-RM, followed by completing the SEQ. On day 2 and 7, participants donated a fasting blood sample, completed the SEQ, ingested the assigned beverage, rested 30 min, and performed a 4 km cycling time-trial (TT). Data were analyzed by univariate, multivariate, and repeated measures general linear models (GLM), adjusted for gender and relative caffeine intake. Data are presented as mean change (95% CI). An overall multivariate time × treatment interaction was observed on strength performance variables (p = 0.01). Acute RTD ingestion better maintained LP 1-RM (PLA: -0.285 (-0.49, -0.08); RTD: 0.23 (-0.50, 0.18) kg/kgFFM, p = 0.30); increased LP RtF (PLA: -2.60 (-6.8, 1.6); RTD: 4.00 (-0.2, 8.2) repetitions, p = 0.031); increased BP lifting volume (PLA: 0.001 (-0.13, 0.16); RTD: 0.03 (0.02, 0.04) kg/kgFFM, p = 0.007); and, increased total lifting volume (PLA: -13.12 (-36.9, 10.5); RTD: 21.06 (-2.7, 44.8) kg/kgFFM, p = 0.046). Short-term RTD ingestion maintained baseline LP 1-RM (PLA: -0.412 (-0.08, -0.07); RTD: 0.16 (-0.50, 0.18) kg/kgFFM, p = 0.30); LP RtF (PLA: 0.12 (-3.0, 3.2); RTD: 3.6 (0.5, 6.7) repetitions, p = 0.116); and, LP lifting volume (PLA: 3.64 (-8.8, 16.1); RTD: 16.25 (3.8, 28.7) kg/kgFFM, p = 0.157) to a greater degree than PLA. No significant differences were observed between treatments in cycling TT performance, hemodynamic assessment, fasting blood panels, or self-reported side effects.


Assuntos
Bebidas , Exercício Físico , Fenômenos Fisiológicos da Nutrição Esportiva , Adulto , Bebidas/análise , Estudos Cross-Over , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Alimentos Formulados , Humanos , Masculino , Força Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Adulto Jovem
9.
Artigo em Inglês | MEDLINE | ID: mdl-28096757

RESUMO

BACKGROUND: The purpose of this study was to examine whether ingesting a pre-workout dietary supplement (PWS) with and without synephrine (S) during training affects training responses in resistance-trained males. METHODS: Resistance-trained males (N = 80) were randomly assigned to supplement their diet in a double-blind manner with either a flavored placebo (PLA); a PWS containing beta-alanine (3 g), creatine nitrate as a salt (2 g), arginine alpha-ketoglutarate (2 g), N-Acetyl-L-Tyrosine (300 mg), caffeine (284 mg), Mucuna pruiriens extract standardized for 15% L-Dopa (15 mg), Vitamin C as Ascorbic Acid (500 mg), niacin (60 mg), folate as folic acid (50 mg), and Vitamin B12 as Methylcobalamin (70 mg); or, the PWS supplement with Citrus aurantium extract containing 20 mg of synephrine (PWS + S) once per day for 8-weeks during training. Participants donated a fasting blood sample and had body composition (DXA), resting heart rate and blood pressure, cognitive function (Stroop Test), readiness to perform, bench and leg press 1 RM, and Wingate anaerobic capacity assessments determined a 0, 4, and 8-weeks of standardized training. Data were analyzed by MANOVA with repeated measures. Performance and cognitive function data were analyzed using baseline values as covariates as well as mean changes from baseline with 95% confidence intervals (CI). Blood chemistry data were also analyzed using Chi-square analysis. RESULTS: Although significant time effects were seen, no statistically significant overall MANOVA Wilks' Lambda interactions were observed among groups for body composition, resting heart and blood pressure, readiness to perform questions, 1RM strength, anaerobic sprint capacity, or blood chemistry panels. MANOVA univariate analysis and analysis of changes from baseline with 95% CI revealed some evidence that cognitive function and 1RM strength were increased to a greater degree in the PWS and/or PWS + S groups after 4- and/or 8-weeks compared to PLA responses. However, there was no evidence that PWS + S promoted greater overall training adaptations compared to the PWS group. Dietary supplementation of PWS and PWS + S did not increase the incidence of reported side effects or significantly affect the number of blood values above clinical norms compared to PLA. CONCLUSION: Results provide some evidence that 4-weeks of PWS and/or PWS + S supplementation can improve some indices of cognitive function and exercise performance during resistance-training without significant side effects in apparently health males. However, these effects were similar to PLA responses after 8-weeks of supplementation and inclusion of synephrine did not promote additive benefits. TRIAL REGISTRATION: This trial (NCT02999581) was retrospectively registered on December 16th 2016.


Assuntos
Suplementos Nutricionais , Resistência Física , Treinamento de Força , Sinefrina/administração & dosagem , beta-Alanina/administração & dosagem , Método Duplo-Cego , Humanos , Masculino , Fenômenos Fisiológicos da Nutrição Esportiva , Resultado do Tratamento , Adulto Jovem
10.
Artigo em Inglês | MEDLINE | ID: mdl-28096758

RESUMO

BACKGROUND: The purpose of this study was to examine the effects of acute ingestion of a pre-workout dietary supplement (PWS) with and without p-synephrine (S) on perceptions of readiness to perform, cognitive function, exercise performance, and markers of safety. METHODS: In a randomized, double-blind, and counterbalanced manner; 25 healthy and recreationally active male and female participants ingested a flavored maltodextrin placebo (PLA), a PWS containing beta-alanine (3 g), creatine nitrate as a salt (2 g), arginine alpha-ketoglutarate (2 g), N-Acetyl-L-Tyrosine (300 mg), caffeine (284 mg), Mucuna pruiriens extract standardized for 15% L-Dopa (15 mg), Vitamin C as Ascorbic Acid (500 mg), niacin (60 mg), folate as folic acid (50 mg), and Vitamin B12 as Methylcobalamin (70 mg) with 2 g of maltodextrin and flavoring; or, the PWS with Citrus aurantium (PWS + S) extract standardized for 30% p-synephrine (20 mg). Participants had heart rate (HR), blood pressure, resting energy expenditure (REE), 12-lead electrocardiograms (ECG), perceptions about readiness to perform, cognitive function (Stroop Color-Word test), bench and leg press performance (2 sets of 10 repetitions at 70% of 1RM and 1 set to failure), and Wingate anaerobic capacity (WAC) sprint performance determined as well as donated blood samples prior to and/or following exercise/supplementation. Data were analyzed by MANOVA with repeated measures as well as mean changes from baseline with 95% confidence intervals (CI). RESULTS: No clinically significant differences were observed among treatments in HR, blood pressure, ECG, or general clinical blood panels. There was evidence that PWS and PWS + S ingestion promoted greater changes in REE responses. Participants reported higher perception of optimism about performance and vigor and energy with PWS and PWS + S ingestion and there was evidence that PWS and PWS + S improved changes in cognitive function scores from baseline to a greater degree than PLA after 1 or 2 h. However, the scores in the PWS + S treatment did not exceed PLA or PWS responses at any data point. No statistically significant differences were observed among treatments in total bench press lifting volume, leg press lifting volume or WAC sprint performance. CONCLUSIONS: Within the confines of this study, ingestion of PWS and/or PWS + S prior to exercise appears to be well-tolerated when consumed by young, healthy individuals. The primary effects appear to be to increase REE responses and improve perceptions about readiness to perform and cognitive function with limited to no effects on muscular endurance and WAC. The addition of 20 mg of p-synephrine to the PWS provided limited to no additive benefits. TRIAL REGISTRATION: This trial (NCT02952014) was retrospectively registered on September 13th 2016.


Assuntos
Suplementos Nutricionais , Treinamento de Força , Sinefrina/administração & dosagem , beta-Alanina/administração & dosagem , Cognição/efeitos dos fármacos , Método Duplo-Cego , Metabolismo Energético/efeitos dos fármacos , Feminino , Humanos , Masculino , Resistência Física/efeitos dos fármacos , Fenômenos Fisiológicos da Nutrição Esportiva , Sinefrina/farmacologia , Resultado do Tratamento , Adulto Jovem , beta-Alanina/farmacologia
11.
Appl Physiol Nutr Metab ; 42(2): 216-227, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28044449

RESUMO

While commercial dietary weight-loss programs typically advise exercise, few provide actual programing. The goal of this study was to compare the Curves Complete 90-day Challenge (CC, n = 29), which incorporates exercising and diet, to programs advocating exercise (Weight Watchers Points Plus (WW, n = 29), Jenny Craig At Home (JC, n = 27), and Nutrisystem Advance Select (NS, n = 28)) or control (n = 20) on metabolic syndrome (MetS) and weight loss. We randomized 133 sedentary, overweight women (age, 47 ± 11 years; body mass, 86 ± 14 kg; body mass index, 35 ± 6 kg/m2) into respective treatment groups for 12 weeks. Data were analyzed using chi square and general linear models adjusted for age and respective baseline measures. Data are means ± SD or mean change ± 95% confidence intervals (CIs). We observed a significant trend for a reduction in energy intake for all treatment groups and significant weight loss for all groups except control: CC (-4.32 kg; 95% CI, -5.75, -2.88), WW (-4.31 kg; 95% CI, -5.82, -2.96), JC (-5.34 kg; 95% CI, -6.86, -3.90), NS (-5.03 kg; 95% CI, -6.49, -3.56), and control (0.16 kg, 95% CI, -1.56, 1.89). Reduced MetS prevalence was observed at follow-up for CC (35% vs. 14%, adjusted standardized residuals (adjres.) = 3.1), but not WW (31% vs. 28% adjres. = 0.5), JC (37% vs. 42%, adjres. = -0.7), NS (39% vs. 50% adjres. = -1.5), or control (45% vs. 55% adjres. = -1.7). While all groups improved relative fitness (mL·kg-1·min-1) because of weight loss, only the CC group improved absolute fitness (L/min). In conclusion, commercial programs offering concurrent diet and exercise programming appear to offer greater improvements in MetS prevalence and cardiovascular function after 12 weeks of intervention.


Assuntos
Dieta Redutora , Exercício Físico , Síndrome Metabólica/prevenção & controle , Obesidade/dietoterapia , Sobrepeso/dietoterapia , Índice de Massa Corporal , Aptidão Cardiorrespiratória , Terapia Combinada/economia , Dieta Redutora/economia , Método Duplo-Cego , Ingestão de Energia , Feminino , Seguimentos , Humanos , Resistência à Insulina , Síndrome Metabólica/epidemiologia , Síndrome Metabólica/etiologia , Pessoa de Meia-Idade , Obesidade/metabolismo , Obesidade/fisiopatologia , Obesidade/terapia , Sobrepeso/metabolismo , Sobrepeso/fisiopatologia , Sobrepeso/terapia , Cooperação do Paciente , Prevalência , Treinamento de Força , Fatores de Risco , Comportamento Sedentário , Texas/epidemiologia , Perda de Peso
12.
J Sports Med Phys Fitness ; 57(5): 572-579, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27058344

RESUMO

BACKGROUND: Among professional pitchers, anthropometric changes and their effect on statistics are relatively unknown. Bivariate analyses and repeated one-way ANOVA evaluated the impact of physical size on baseball pitching statistics and attributes within an elite talent sample of Major League pitching leaders. METHODS: Body Mass Index (BMI) was calculated from publicly available players' heights and weights to form a statistical database of 1028 pitching leaders from 1950-2010. Repeated measures ANOVAs examined differences in anthropometrics and baseball statistics between decades 1950-2010. Bivariate correlation evaluated BMI as an independent variable of influence on statistics, where all tests applied an a-priori significance level (P<0.05). RESULTS: BMI increased throughout the sixty year period with weight growth greater than height (P<0.001). Increased BMI reported earlier signing age, and age of debut (P<0.05), where larger pitchers showed small positive correlation seen among saves (P<0.001) concurrent to negative correlation with innings pitched and complete games (P≤0.001), as well as shutouts (P<0.05). A contrast between saves and complete games pitched was found where saves increased over time (P<0.001) while complete games pitched declined (P<0.001). CONCLUSIONS: Over time, throwing workloads showed better management for larger starting pitchers with less innings pitched and complete games thrown added to an extra rest day in the pitching rotation. In contrast, paralleled increases in physical size with recorded saves at present requires greater medical and training attention to protecting the throwing arm of the larger relief pitchers, as increased body size can increase force properties and ball velocity owing to greater injury risks.


Assuntos
Desempenho Atlético/fisiologia , Beisebol , Ligamentos Colaterais/fisiologia , Articulação do Cotovelo/fisiologia , Articulação do Ombro/fisiologia , Adulto , Análise de Variância , Beisebol/lesões , Estatura , Índice de Massa Corporal , Peso Corporal , Humanos , Masculino , Estados Unidos
13.
J Int Soc Sports Nutr ; 13: 38, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27777542

RESUMO

BACKGROUND: Limited research exists on the effect of a sports dietitian (SD) on athletes' dietary habits and nutrient periodization, which is the deliberate manipulation of macronutrient intake to match training goals. Further, the difference in dietary habits between men and women collegiate athletes has been understudied. A survey questionnaire examining dietary habits and practices was administered to athletes at two universities that employed a full time SD. Not all athletes used the SD as their primary source for nutritional guidance. The purposes were to examine the effect of a SD as a primary source of nutrition information, and the effect of gender on dietary habits in collegiate athletes. METHODS: Three hundred eighty-three women (n = 240) and men (n = 143) student-athletes (mean ± SD: age = 19.7 ± 1.4 years) from 10 collegiate sports took a 15-min survey consisting of questions on dietary habits and practices. Topics queried included eating habits, breakfast habits, hydration habits, nutritional supplementation use, pre-workout nutrition, post-workout nutrition, nutrition during team trips, and nutrient timing. Data were sorted by the athlete's source of nutritional information (i.e., sport dietitian, other). Data analysis consisted of descriptive statistics and 2-way Pearson X2 analyses (p ≤ 0.10). RESULTS: When a SD was indicated as the primary nutrition information source, athletes appeared to have a greater understanding of nutrient periodization (47.12 % vs. 32.85 %), were more likely to have school-provided boxed meals while on team trips (21.29 % vs. 6.77 %), and also less likely to consume fast food while on team trips (9.90 % vs. 19.55 %). Men athletes consumed fast food or restaurant meals more frequently, had higher weekly and more frequent alcohol intake during the competitive season. Women athletes were more likely to prepare meals, eat breakfast 7 days a week, and have school-provided boxed meals. CONCLUSIONS: Positive effects on dietary habits were observed when a SD was the primary nutrition information source. Practitioners should be aware of the gender differences in alcohol intake, fast food consumption, and knowledge of nutrient periodization. Collegiate athletes and athletic staff members could benefit from SD access to safeguard against dietary habits detrimental to performance.


Assuntos
Atletas , Acesso aos Serviços de Saúde , Ciências da Nutrição e do Esporte , Esportes , Registros de Dieta , Ingestão de Energia , Comportamento Alimentar , Feminino , Fidelidade a Diretrizes , Guias como Assunto , Humanos , Masculino , Avaliação Nutricional , Necessidades Nutricionais , Fatores Sexuais , Universidades , Adulto Jovem
14.
J Int Soc Sports Nutr ; 13: 22, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27231439

RESUMO

BACKGROUND: The purpose of this study was to determine whether short-term supplementation of a powdered tart cherry supplement prior to and following stressful endurance exercise would affect markers of muscle damage, inflammation, oxidative stress, and/or muscle soreness. METHODS: 27 endurance-trained runners or triathlete (21.8 ± 3.9 years, 15.0 ± 6.0 % body fat, 67.4 ± 11.8 kg) men (n = 18) and women (n = 9) were matched based on average reported race pace, age, body mass, and fat free mass. Subjects were randomly assigned to ingest, in a double-blind manner, capsules containing 480 mg of a rice flour placebo (P, n = 16) or powdered tart cherries [CherryPURE®] (TC, n = 11). Subjects supplemented one time daily (480 mg/day) for 10-d, including race day, up to 48-hr post-run. Subjects completed a half-marathon run (21.1 km) under 2-hr (111.98 ± 11.9 min). Fasting blood samples and quadriceps muscle soreness ratings using an algometer with a graphic pain rating scale were taken pre-run, 60-min, 24 and 48-h post-run and analyzed by MANOVA with repeated measures. RESULTS: Subjects in the TC group averaged 13 % faster half-marathon race finish times (p = 0.001) and tended to have smaller deviations from predicted race pace (p = 0.091) compared to P. Attenuations in TC muscle catabolic markers were reported over time for creatinine (p = 0.047), urea/blood urea nitrogen (p = 0.048), total protein (p = 0.081), and cortisol (p = 0.016) compared to P. Despite lower antioxidant activity pre-run in TC compared to P, changes from pre-run levels revealed a linear increase in antioxidant activity at 24 and 48-h of recovery in TC that was statistically different (16-39 %) from P and pre-run levels. Inflammatory markers were 47 % lower in TC compared to P over time (p = 0.053) coupled with a significant difference between groups (p = 0.017). Soreness perception between the groups was different over time in the medial quadriceps (p = 0.035) with 34 % lower pre-run soreness in TC compared to P. Over the 48-h recovery period, P changes in medial quadriceps soreness from pre-run measures were smaller compared to TC. CONCLUSION: Results revealed that short-term supplementation of Montmorency powdered tart cherries surrounding an endurance challenge attenuated markers of muscle catabolism, reduced immune and inflammatory stress, better maintained redox balance, and increased performance in aerobically trained individuals.


Assuntos
Resistência Física , Prunus avium , Adolescente , Adulto , Antioxidantes/análise , Biomarcadores/sangue , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Humanos , Imunidade , Inflamação , Masculino , Músculo Esquelético/metabolismo , Mialgia , Oxirredução , Fitoterapia , Placebos , Prunus avium/química , Músculo Quadríceps , Corrida , Adulto Jovem
15.
J Int Soc Sports Nutr ; 13: 12, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27034623

RESUMO

BACKGROUND: Creatine monohydrate (CrM) and nitrate are popular supplements for improving exercise performance; yet have not been investigated in combination. We performed two studies to determine the safety and exercise performance-characteristics of creatine nitrate (CrN) supplementation. METHODS: Study 1 participants (N = 13) ingested 1.5 g CrN (CrN-Low), 3 g CrN (CrN-High), 5 g CrM or a placebo in a randomized, crossover study (7d washout) to determine supplement safety (hepatorenal and muscle enzymes, heart rate, blood pressure and side effects) measured at time-0 (unsupplemented), 30-min, and then hourly for 5-h post-ingestion. Study 2 participants (N = 48) received the same CrN treatments vs. 3 g CrM in a randomized, double-blind, 28d trial inclusive of a 7-d interim testing period and loading sequence (4 servings/d). Day-7 and d-28 measured Tendo™ bench press performance, Wingate testing and a 6x6-s bicycle ergometer sprint. Data were analyzed using a GLM and results are reported as mean ± SD or mean change ± 95 % CI. RESULTS: In both studies we observed several significant, yet stochastic changes in blood markers that were not indicative of potential harm or consistent for any treatment group. Equally, all treatment groups reported a similar number of minimal side effects. In Study 2, there was a significant increase in plasma nitrates for both CrN groups by d-7, subsequently abating by d-28. Muscle creatine increased significantly by d-7 in the CrM and CrN-High groups, but then decreased by d-28 for CrN-High. By d-28, there were significant increases in bench press lifting volume (kg) for all groups (PLA, 126.6, 95 % CI 26.3, 226.8; CrM, 194.1, 95 % CI 89.0, 299.2; CrN-Low, 118.3, 95 % CI 26.1, 210.5; CrN-High, 267.2, 95 % CI 175.0, 359.4, kg). Only the CrN-High group was significantly greater than PLA (p < 0.05). Similar findings were observed for bench press peak power (PLA, 59.0, 95 % CI 4.5, 113.4; CrM, 68.6, 95 % CI 11.4, 125.8; CrN-Low, 40.9, 95 % CI -9.2, 91.0; CrN-High, 60.9, 95 % CI 10.8, 111.1, W) and average power. CONCLUSIONS: Creatine nitrate delivered at 3 g was well-tolerated, demonstrated similar performance benefits to 3 g CrM, in addition, within the confines of this study, there were no safety concerns.


Assuntos
Limiar Anaeróbio/efeitos dos fármacos , Suplementos Nutricionais , Força Muscular/efeitos dos fármacos , Nitratos/administração & dosagem , Resistência Física/efeitos dos fármacos , Aptidão Física/fisiologia , Levantamento de Peso/fisiologia , Adulto , Limiar Anaeróbio/fisiologia , Desempenho Atlético , Pressão Sanguínea/efeitos dos fármacos , Creatina , Estudos Cross-Over , Relação Dose-Resposta a Droga , Método Duplo-Cego , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Força Muscular/fisiologia , Músculo Esquelético/efeitos dos fármacos
16.
Metab Syndr Relat Disord ; 14(4): 228-37, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26554616

RESUMO

BACKGROUND: To examine the effect of protein-focused (PRO, 1.14 g/kg/day) and carbohydrate-focused (CHO, ∼2.2 g/kg/day) diets (∼1600 kcals) combined with 10 weeks of circuit exercise training in sedentary overweight/obese women (N = 661, age 46 ± 11 years) on metabolic syndrome (MetS). METHODS: We retrospectively analyzed eight exercise training studies performed from 2002-2014. Primary (MetS), secondary (MetS z-scores and individual MetS components), and tertiary outcomes [body mass index (BMI) by WHO cut points] were analyzed using chi-square, GLM, and McNemar's tests. RESULTS: Both groups experienced significant weight loss, improvements in fitness, and reductions in MetS prevalence from baseline to follow-up (PRO: 49% to 42%, CHO: 42% to 36%, both P < 0.01). MetS z-score improvement (∼66.5%) was similar for both groups with no significant between-group differences noted. There were also no significant differences for individual component features between groups for the following: waist circumference (-0.28 ± 0.02 vs. -0.28 ± 0.025 cm, P = 0.97), glucose (-0.07 ± 0.03 vs. -0.08 ± 0.04 mM, P = 0.87), triglycerides (-0.16 ± 0.04 vs. -0.09 ± 0.04 mM, P = 0.20), high-density lipoprotein cholesterol (-0.21 ± 0.03 vs. -0.19 ± 0.04 mM, P = 0.68), and systolic BP (-0.16 ± 0.4 vs. -0.24 ± 0.05 mmHg, P = 0.26). Diastolic BP showed a minor advantage for the PRO group (-0.14 ± 0.05 vs. -0.30 ± 0.05 mmHg P = 0.02). When stratified by BMI, those with morbid obesity did not show a significant improvement in MetS while following a PRO-focused diet; however, caution is warranted given the exploratory nature of this analysis. CONCLUSIONS: Our findings suggest that a low-moderate calorie diet partitioned for CHO and PRO preference is equally effective when combined with a structured exercise program for reducing the prevalence of MetS prevalence in overweight/obese women.


Assuntos
Dieta , Terapia por Exercício , Síndrome Metabólica/complicações , Síndrome Metabólica/epidemiologia , Obesidade/complicações , Sobrepeso/complicações , Adulto , Antropometria , Glicemia/metabolismo , Pressão Sanguínea , Índice de Massa Corporal , Carboidratos da Dieta/administração & dosagem , Proteínas na Dieta/administração & dosagem , Feminino , Humanos , Síndrome Metabólica/prevenção & controle , Pessoa de Meia-Idade , Obesidade/terapia , Sobrepeso/terapia , Prevalência , Estudos Retrospectivos , Resultado do Tratamento , Perda de Peso
17.
J Int Soc Sports Nutr ; 12: 41, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26578852

RESUMO

BACKGROUND: The purpose of this study was to examine whether short-term ingestion of a powdered tart cherry supplement prior to and following intense resistance-exercise attenuates muscle soreness and recovery strength loss, while reducing markers of muscle damage, inflammation, and oxidative stress. METHODS: Twenty-three healthy, resistance-trained men (20.9 ± 2.6 yr, 14.2 ± 5.4% body fat, 63.9 ± 8.6 kg FFM) were matched based on relative maximal back squat strength, age, body weight, and fat free mass. Subjects were randomly assigned to ingest, in a double blind manner, capsules containing a placebo (P, n = 12) or powdered tart cherries [CherryPURE(®)] (TC, n = 11). Participants supplemented one time daily (480 mg/d) for 10-d including day of exercise up to 48-h post-exercise. Subjects performed ten sets of ten repetitions at 70% of a 1-RM back squat exercise. Fasting blood samples, isokinetic MVCs, and quadriceps muscle soreness ratings were taken pre-lift, 60-min, 24-h, and 48-h post-lift and analyzed by MANOVA with repeated measures. RESULTS: Muscle soreness perception in the vastus medialis (») (p = 0.10) and the vastus lateralis (») (p = 0.024) was lower in TC over time compared to P. Compared to pre-lift, TC vastus medialis (») soreness was significantly attenuated up to 48-h post-lift with vastus lateralis (») soreness significantly lower at 24-h post-lift compared to P. TC changes in serum creatinine (p = 0.03, delta p = 0.024) and total protein (p = 0.018, delta p = 0.006) were lower over time and smaller from pre-lift levels over time compared to P Significant TC group reductions from pre-lift levels were found for AST and creatinine 48-h post-lift, bilirubin and ALT 60-min and 48-h post-lift. No significant supplementation effects were observed for serum inflammatory or anti-inflammatory markers. None of the free radical production, lipid peroxidation, or antioxidant capacity markers (NT, TBARS, TAS, SOD) demonstrated significant changes with supplementation. Changes in TC whole blood lymphocyte counts (p = 0.013) from pre-lift were greater compared to P, but TC lymphocyte counts returned to pre-lift values quicker than P. CONCLUSION: Short-term supplementation of Montmorency powdered tart cherries surrounding a single bout of resistance exercise, appears to be an effective dietary supplement to attenuate muscle soreness, strength decrement during recovery, and markers of muscle catabolism in resistance trained individuals.


Assuntos
Antioxidantes/administração & dosagem , Suplementos Nutricionais , Força Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Prunus avium , Treinamento de Força , Adulto , Método Duplo-Cego , Humanos , Inflamação/prevenção & controle , Masculino , Contração Muscular/fisiologia , Força Muscular/fisiologia , Músculo Esquelético/fisiologia , Mialgia/prevenção & controle , Fenômenos Fisiológicos da Nutrição Esportiva , Coxa da Perna , Resultado do Tratamento
18.
Amino Acids ; 47(6): 1203-13, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25740607

RESUMO

The purpose of this study was to determine if the co-ingestion of carbohydrate (CHO) with branched-chain amino acids (BCAA) or L-leucine (LEU) preferentially affected serum IGF-1 and the expression of myogenic-related genes in response to resistance exercise (RE). Forty-one college-age males were randomly assigned to 1 of 4 groups: CHO, CHO-BCAA, CHO-LEU, or placebo (PLC). Resistance exercise consisted of 4 sets of 10 repetitions of leg press and leg extension at 80 % 1RM. Supplements were ingested peri-exercise, and venous blood and muscle biopsies were obtained pre-exercise (PRE), and at 30, 120, and 360 min post-exercise. Serum IGF-1 was determined with ELISA, and skeletal muscle mRNA expression of myostatin, ACTRIIB, p21kip, p27kip, CDK2, cyclin B1, cyclin D1, Myo-D, myogenin, MRF-4, and myf5 was determined using real-time PCR. Results were analyzed by two-way ANOVA for serum IGF-1 and two-way MANOVA for mRNA expression. Serum IGF-1 in CHO + BCAA was greater than PLC (p < 0.05) but was not affected by RE (p > 0.05). A significant group × time interaction was located for cylin D1 (p < 0.05), but not for any other genes. However, significant time effects were noted for cyclin B1 and p21cip (p < 0.05). At 30, 120 and 360 min post-exercise, p21cip was significantly less than PRE. Cyclin D1 was greater than PRE and 30 min post-exercise at 120 and 360 min post-exercise, whereas cyclin B1 was significantly greater than PRE at 120 min post-exercise (p < 0.05). Unlike the co-ingestion of CHO with either BCAA or L-leucine in conjunction with RE, the expression of various myogenically related genes were up-regulated with RE.


Assuntos
Carboidratos da Dieta/administração & dosagem , Regulação da Expressão Gênica/efeitos dos fármacos , Fator de Crescimento Insulin-Like I/biossíntese , Leucina/administração & dosagem , Proteínas Musculares/biossíntese , Resistência Física/efeitos dos fármacos , Adolescente , Adulto , Regulação da Expressão Gênica/fisiologia , Humanos , Masculino , Resistência Física/fisiologia
19.
J Neurosci ; 35(2): 666-77, 2015 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-25589761

RESUMO

Maternal social stress during late pregnancy programs hypothalamo-pituitary-adrenal (HPA) axis hyper-responsiveness to stressors, such that adult prenatally stressed (PNS) offspring display exaggerated HPA axis responses to a physical stressor (systemic interleukin-1ß; IL-1ß) in adulthood, compared with controls. IL-1ß acts via a noradrenergic relay from the nucleus tractus solitarii (NTS) to corticotropin releasing hormone neurons in the paraventricular nucleus (PVN). Neurosteroids can reduce HPA axis responses, so allopregnanolone and 3ß-androstanediol (3ß-diol; 5α-reduced metabolites of progesterone and testosterone, respectively) were given subacutely (over 24 h) to PNS rats to seek reversal of the "programmed" hyper-responsive HPA phenotype. Allopregnanolone attenuated ACTH responses to IL-1ß (500 ng/kg, i.v.) in PNS females, but not in PNS males. However, 3ß-diol normalized HPA axis responses to IL-1ß in PNS males. Impaired testosterone and progesterone metabolism or increased secretion in PNS rats was indicated by greater plasma testosterone and progesterone concentrations in male and female PNS rats, respectively. Deficits in central neurosteroid production were indicated by reduced 5α-reductase mRNA levels in both male and female PNS offspring in the NTS, and in the PVN in males. In PNS females, adenovirus-mediated gene transfer was used to upregulate expression of 5α-reductase and 3α-hydroxysteroid dehydrogenase mRNAs in the NTS, and this normalized hyperactive HPA axis responses to IL-1ß. Thus, downregulation of neurosteroid production in the brain may underlie HPA axis hyper-responsiveness in prenatally programmed offspring, and administration of 5α-reduced steroids acutely to PNS rats overrides programming of hyperactive HPA axis responses to immune challenge in a sex-dependent manner.


Assuntos
Androstano-3,17-diol/farmacologia , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Pregnanolona/farmacologia , Estresse Psicológico/tratamento farmacológico , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/genética , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/metabolismo , 3-alfa-Hidroxiesteroide Desidrogenase (B-Específica)/genética , 3-alfa-Hidroxiesteroide Desidrogenase (B-Específica)/metabolismo , Androstano-3,17-diol/uso terapêutico , Animais , Feminino , Sistema Hipotálamo-Hipofisário/crescimento & desenvolvimento , Interleucina-1beta/farmacologia , Masculino , Núcleo Hipotalâmico Paraventricular/efeitos dos fármacos , Núcleo Hipotalâmico Paraventricular/crescimento & desenvolvimento , Núcleo Hipotalâmico Paraventricular/metabolismo , Sistema Hipófise-Suprarrenal/crescimento & desenvolvimento , Gravidez , Complicações na Gravidez/tratamento farmacológico , Pregnanolona/uso terapêutico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Fatores Sexuais , Núcleo Solitário/efeitos dos fármacos , Núcleo Solitário/crescimento & desenvolvimento , Núcleo Solitário/metabolismo
20.
Ann Rheum Dis ; 74(12): 2123-9, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25074688

RESUMO

OBJECTIVES: OSKIRA-4 evaluated the efficacy of fostamatinib monotherapy versus placebo on the signs and symptoms of rheumatoid arthritis over 6 weeks by Disease Activity Score C reactive protein (DAS-28(CRP)) and assessed non-inferiority to adalimumab monotherapy at Week 24 by DAS-28(CRP). METHODS: Overall, 279 patients not currently taking disease-modifying antirheumatic drugs were randomised to: (A) fostamatinib 100 mg twice daily for 24 weeks plus placebo injection every 2 weeks (PBOI); (B) fostamatinib 100 mg twice daily for 4 weeks, then 150 mg once daily up to Week 24, plus PBOI; (C) fostamatinib 100 mg twice daily for 4 weeks, then 100 mg once daily up to Week 24, plus PBOI; (D) adalimumab 40 mg every 2 weeks for 24 weeks, plus oral placebo twice daily; or (E) oral placebo twice daily for 6 weeks, plus PBOI, then a switch to arm A or B. RESULTS: Fostamatinib demonstrated a significant improvement in DAS-28(CRP) score from baseline versus placebo at Week 6 for arms A and B, but not C. Fostamatinib was significantly less effective than adalimumab at Week 24 based on DAS-28(CRP). Adverse events observed with fostamatinib treatment were consistent with those reported in previous studies, including hypertension and diarrhoea. CONCLUSIONS: Fostamatinib demonstrated efficacy as monotherapy, showing superior DAS-28(CRP) score changes between baseline and 6 weeks when compared with placebo in treatment arms A and B. However, all fostamatinib regimens demonstrated inferior responses compared with adalimumab at Week 24. TRIAL REGISTRATION NUMBER: Clinicaltrials.gov: NCT01264770.


Assuntos
Artrite Reumatoide/tratamento farmacológico , Oxazinas/administração & dosagem , Piridinas/administração & dosagem , Adalimumab/administração & dosagem , Administração Oral , Adulto , Idoso , Aminopiridinas , Antirreumáticos/administração & dosagem , Artrite Reumatoide/sangue , Artrite Reumatoide/diagnóstico , Proteína C-Reativa/metabolismo , Relação Dose-Resposta a Droga , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Seguimentos , Humanos , Injeções Subcutâneas , Masculino , Pessoa de Meia-Idade , Morfolinas , Pirimidinas , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto Jovem
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