RESUMEN
The purpose was to compare the effects of protein (whey protein) and carbohydrate supplementation and protein alone both combined with resistance training on muscle strength, muscle mass and total training volume progression in untrained young men. Resistance training was performed using the leg press and knee extension until concentric failure (8-12 repetition maximum), three times a week for eight weeks. Muscle strength and muscle cross-sectional area were assessed before and after training. Total training volume progression was calculated considering the first and eighth week. Seventeen men completed the study (protein and carbohydrate, n=9, age 23.44 ± 4.56 years, weight: 62.13±6.17 kg, height: 1.75±0.02 m, body mass index: 20.29±2.08 kg/m2; protein, n=8, age 24.63±2.39 years, weight: 69.01±5.57 kg, height: 1.77±0.07 m; body mass index: 21.64±1.05 kg/m2. Both protocols showed similar increases in muscle strength (effect size: protein and carbohydrate=1.28; protein=0.97; p<0.001), muscle cross sectional area (effect size: protein and carbohydrate=0.66; protein=0.47; p<0.001) and total training volume progression (effect size: protein and carbohydrate=2.68; protein=1.63; p<0.001) after training. No differences were found between groups p>0.05). Protein and carbohydrate supplementation combined with resistance training does not induce greater gains in muscle strength, hypertrophy and total training volume compared to resistance training combined with protein alone in untrained individuals.
Asunto(s)
Adaptación Fisiológica , Carbohidratos de la Dieta/administración & dosificación , Suplementos Dietéticos , Músculo Esquelético/fisiología , Entrenamiento de Fuerza/métodos , Proteína de Suero de Leche/administración & dosificación , Adolescente , Adulto , Humanos , Rodilla/fisiología , Pierna/fisiología , Masculino , Fuerza Muscular , Músculo Esquelético/anatomía & histología , Crecimiento del Músculo Esquelético , Adulto JovenRESUMEN
Based on the fact that taurine can increase lipid metabolism, the objective of the present study was to evaluate the effects of different doses of acute taurine supplementation on lipid oxidation levels in healthy young men after a single bout of fasting aerobic exercise. A double-blind, acute, and crossover study design was conducted. Seventeen men (age 24.8 ± 4.07y; BMI: 23.9 ± 2.57 kg/m²) participated in the present study. Different doses of taurine (TAU) (3 g or 6 g) or placebo were supplemented 90 minutes before a single bout of fasting aerobic exercise (on a treadmill at 60% of VO2 max). The subjects performed three trials, and each one was separated by seven days. Blood samples were collected at baseline and after the exercise protocol of each test to analyze plasma levels of glycerol and taurine. Lipid and carbohydrate oxidation were determined immediately after exercise for 15 minutes by indirect calorimetry. We observed that TAU supplementation (6 g) increased lipid oxidation (38%) and reduced the respiratory coefficient (4%) when compared to the placebo (p < 0.05). However, no differences in lipid oxidation were observed between the different doses of taurine (3 g and 6 g). For glycerol concentrations, there were no differences between trials. Six grams of TAU supplementation 90 minutes before a single bout of aerobic exercise in a fasted state was sufficient to increase the lipid oxidation post-exercise in healthy young men.
Asunto(s)
Suplementos Dietéticos , Ejercicio Físico , Ayuno , Metabolismo de los Lípidos/efectos de los fármacos , Taurina/administración & dosificación , Adulto , Índice de Masa Corporal , Peso Corporal , Calorimetría Indirecta , Estudios Cruzados , Método Doble Ciego , Prueba de Esfuerzo , Humanos , Masculino , Oxidación-Reducción/efectos de los fármacos , Consumo de Oxígeno/efectos de los fármacos , Taurina/sangre , Adulto JovenRESUMEN
PURPOSE: Açai pulp is a source of phytochemicals and has been associated with antioxidant, anti-inflammatory, and antigenotoxic effects. This study aimed to assess the effects of açai pulp consumption on oxidative, inflammatory, and aerobic capacity markers of cyclist athletes. RESEARCH METHODS AND PROCEDURES: A crossover, randomized, placebo-controlled, single-blind study was developed with ten male cyclists (33.5 ± 4.7 years old, body mass index of 23.9 ± 1.38 kg/m2, and training load around 1875 ± 238 AU/week). The athletes consumed 400 g/day of pasteurized açai pulp (AP) or placebo (PL) for 15 days, with a 30-day wash-out period between trials. Lipid peroxidation, serum antioxidant capacity, DNA damage in peripheral blood (Comet assay), IL-6 and TNF-alpha, blood lactate concentration during effort, anaerobic threshold intensity (ATi), maximum workload reached (Wmax), rating of perceived exertion threshold (RPET), and heart rate threshold (HRT) were evaluated before and after each intervention. Data were analyzed using a linear regression model with mixed effects (p ≤ 0.05). RESULTS: Increased serum antioxidant capacity (p = 0.006) and decreased lipid peroxidation (p = 0.01) were observed in subjects after intervention with AP. Blood lactate levels during effort significantly decreased (by 29%, p = 0.025) and ATi increased (p = 0.006) after AP. No significant effect on DNA damage was attributed to AP consumption. CONCLUSION: We found notable effects of AP intervention on antioxidant status in athletes. Both the reduction in blood lactate concentration and increase in ATi during the effort suggest an overall improvement in the aerobic capacity of the cyclists, confirming that AP consumption may influence variables associated with performance in endurance athletes.