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1.
J Am Coll Nutr ; 33(4): 247-55, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25140763

RESUMO

PURPOSE: The purpose of this study was to determine the effects of a multinutritional supplement including amino acids, ß-hydroxy-ß-methylbutyrate (HMB), and carbohydrates on cytokine responses to resistance exercise and training. METHODS: Seventeen healthy, college-aged men were randomly assigned to a Muscle Armor™ (MA; Abbott Nutrition, Columbus, OH) or placebo supplement group and 12 weeks of resistance training. An acute resistance exercise protocol was administered at 0, 6, and 12 weeks of training. Venous blood samples at pre-, immediately post-, and 30-minutes postexercise were analyzed via bead multiplex immunoassay for 17 cytokines. RESULTS: After 12 weeks of training, the MA group exhibited decreased interferon-gamma (IFN-γ) and interleukin (IL)-10. IL-1ß differed by group at various times. Granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), IL-6, IL-7, IL-8, IL-12p70, IL-13, IL-17, monocyte chemoattractant protein-1 (MCP-1), and macrophage inflammatory protein-1 beta (MIP-1ß) changed over the 12-week training period but did not differ by group. CONCLUSIONS: Twelve weeks of resistance training alters the cytokine response to acute resistance exercise, and supplementation with HMB and amino acids appears to further augment this result.


Assuntos
Citocinas/sangue , Carboidratos da Dieta/administração & dosagem , Suplementos Nutricionais , Treinamento Resistido , Valeratos/administração & dosagem , Aminoácidos/administração & dosagem , Índice de Massa Corporal , Peso Corporal , Quimiocina CCL2/sangue , Quimiocina CCL4/sangue , Método Duplo-Cego , Voluntários Saudáveis , Humanos , Interferon gama/sangue , Interleucina-10/sangue , Interleucina-13/sangue , Interleucina-1beta/sangue , Interleucina-6/sangue , Interleucina-8/sangue , Masculino , Micronutrientes/administração & dosagem , Avaliação Nutricional , Adulto Jovem
2.
J Am Coll Nutr ; 32(1): 66-74, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24015701

RESUMO

OBJECTIVE: For many resistance-trained men concerns exist regarding the production of estrogen with the consumption of soy protein when training for muscle strength and size. Thus, the purpose of this investigation was to examine the effects of soy and whey protein supplementation on sex hormones following an acute bout of heavy resistance exercise in resistance trained men. METHODS: Ten resistance-trained men (age 21.7 ± 2.8 [SD] years; height 175.0 ± 5.4 cm; weight 84.2 ± 9.1 kg) volunteered to participate in an investigation. Utilizing a within subject randomized crossover balanced placebo design, all subjects completed 3 experimental treatment conditions supplementing with whey protein isolate (WPI), soy protein isolate (SPI), and maltodextrin placebo control for 14 days with participants ingesting 20 g of their assigned supplement each morning at approximately the same time each day. Following supplementation, subjects performed an acute heavy resistance exercise test consisting of 6 sets of 10 repetitions in the squat exercise at 80% of the subject's one repetition maximum. RESULTS: This investigation observed lower testosterone responses following supplementation with soy protein in addition to a positive blunted cortisol response with the use of whey protein at some recovery time points. Although sex hormone binding globulin (SHBG) was proposed as a possible mechanism for understanding changes in androgen content, SHBG did not differ between experimental treatments. Importantly, there were no significant differences between groups in changes in estradiol concentrations. CONCLUSION: Our main findings demonstrate that 14 days of supplementation with soy protein does appear to partially blunt serum testosterone. In addition, whey influences the response of cortisol following an acute bout of resistance exercise by blunting its increase during recovery. Protein supplementation alters the physiological responses to a commonly used exercise modality with some differences due to the type of protein utilized.


Assuntos
Suplementos Nutricionais , Exercício Físico/fisiologia , Hidrocortisona/sangue , Proteínas do Leite/farmacologia , Treinamento Resistido , Proteínas de Soja/farmacologia , Testosterona/sangue , Adulto , Estudos Cross-Over , Proteínas Alimentares/farmacologia , Estradiol/sangue , Teste de Esforço , Humanos , Masculino , Polissacarídeos/farmacologia , Globulina de Ligação a Hormônio Sexual/metabolismo , Glycine max/química , Proteínas do Soro do Leite , Adulto Jovem
3.
J Am Coll Nutr ; 32(2): 122-35, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24015719

RESUMO

UNLABELLED: Compared to soy, whey protein is higher in leucine, absorbed quicker and results in a more pronounced increase in muscle protein synthesis. OBJECTIVE: To determine whether supplementation with whey promotes greater increases in muscle mass compared to soy or carbohydrate, we randomized non-resistance-trained men and women into groups who consumed daily isocaloric supplements containing carbohydrate (carb; n = 22), whey protein (whey; n = 19), or soy protein (soy; n = 22). METHODS: All subjects completed a supervised, whole-body periodized resistance training program consisting of 96 workouts (~9 months). Body composition was determined at baseline and after 3, 6, and 9 months. Plasma amino acid responses to resistance exercise followed by supplement ingestion were determined at baseline and 9 months. RESULTS: Daily protein intake (including the supplement) for carb, whey, and soy was 1.1, 1.4, and 1.4 g·kg body mass⁻¹, respectively. Lean body mass gains were significantly (p < 0.05) greater in whey (3.3 ± 1.5 kg) than carb (2.3 ± 1.7 kg) and soy (1.8 ± 1.6 kg). Fat mass decreased slightly but there were no differences between groups. Fasting concentrations of leucine were significantly elevated (20%) and postexercise plasma leucine increased more than 2-fold in whey. Fasting leucine concentrations were positively correlated with lean body mass responses. CONCLUSIONS: Despite consuming similar calories and protein during resistance training, daily supplementation with whey was more effective than soy protein or isocaloric carbohydrate control treatment conditions in promoting gains in lean body mass. These results highlight the importance of protein quality as an important determinant of lean body mass responses to resistance training.


Assuntos
Suplementos Nutricionais , Proteínas do Leite/administração & dosagem , Treinamento Resistido , Adulto , Aminoácidos/sangue , Índice de Massa Corporal , Carboidratos da Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Método Duplo-Cego , Feminino , Humanos , Leucina/sangue , Masculino , Proteínas Musculares/biossíntese , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Estudos Prospectivos , Proteínas de Soja/administração & dosagem , Proteínas do Soro do Leite , Adulto Jovem
4.
Nutr J ; 10: 90, 2011 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-21899733

RESUMO

BACKGROUND: While exercise acts to combat inflammation and aging, the ability to exercise may itself be compromised by inflammation and inflammation's impact on muscle recovery and joint inflammation. A number of nutritional supplements have been shown to reduce inflammation and improve recovery. The purpose of the current investigation was to examine the effect of a multi-nutrient supplement containing branched chain amino acids, taurine, anti-inflammatory plant extracts, and B vitamins on inflammatory status, endothelial function, physical function, and mood in middle-aged individuals. METHODS: Thirty-one healthy and active men (N = 16, mean age 56 ± 6.0 yrs) and women (N = 15, mean age = 52 ± 7.5 yrs) participated in this investigation. Subjects completed one 28 day cycle of placebo supplementation and one 28 day cycle of multi-nutrient supplementation (separated by a one week washout period) in a balanced, randomized, double-blind, cross-over design. Subjects completed weekly perceptual logs (PROMIS-57, KOOS) and pre- and post- testing around the supplementation period. Testing consisted of brachial artery flow mediated dilation (FMD), blood measures, and physical performance on vertical jump, handgrip strength, and balance (dispersion from center of pressure). Significance for the investigation was p ≤ 0.05. RESULTS: IL-6 significantly decreased in both men (from 1.2 ± 0.2 to 0.7 ± 0.4 pg·mL(-1)) and women (from 1.16 ± 0.04 to 0.7 ± 0.4 pg·mL(-1)). Perceived energy also improved for both men (placebo: 1.8 ± 0.7; supplement: 3.7 ± 0.8 AUC) and women (placebo: 1.2 ± 0.7; supplement: 2.8 ± 0.8 AUC). Alpha-1-antichymotrypsin (from 108.9 ± 38.6 to 55.5 ± 22.2 ug·mL(-1)), Creatine Kinase (from 96 ± 34 to 67 ± 23 IU·L(-1)), general pain, and joint pain decreased in men only, while anxiety and balance (from 0.52 ± 0.13 to 0.45 ± 0.12 cm) improved in women only. Men showed increased performance in vertical jump power (from 2642 ± 244 to 3134 ± 282 W) and grip strength (from 42.1 ± 5.9 to 48.5 ± 4.9 kg). CONCLUSIONS: A multi-nutrient supplement is effective in improving inflammatory status in both men and women, markers of pain, joint pain, strength, and power in men only, and both anxiety and balance (a risk factor for hip fracture) in women. Therefore, a multi-nutrient supplement may help middle-aged individuals to prolong physical function and maintain a healthy, active lifestyle.


Assuntos
Suplementos Nutricionais , Inflamação/tratamento farmacológico , Aptidão Física/fisiologia , Envelhecimento , Creatina Quinase/metabolismo , Método Duplo-Cego , Exercício Físico , Feminino , Humanos , Interleucina-6/sangue , Masculino , Pessoa de Meia-Idade , alfa 1-Antiquimotripsina/metabolismo
5.
Metabolism ; 59(8): 1190-9, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20045157

RESUMO

The purpose of this study was to examine the effects of Carnipure tartrate (Lonza, Allendale, NJ) supplementation (total dose of 2 g/d of l-carnitine) on markers of performance and recovery from physical exertion in middle-aged men and women. Normally active and healthy men (n = 9, 45.4 +/- 5.3 years old) and women (n = 9, 51.9 +/- 5.0 years old) volunteered to participate in the investigation. Double-blind, placebo, balanced treatment presentation and crossover design were used with 3 weeks and 3 days of supplementation followed by a 1-week washout period before the other counterbalanced treatment was initiated. After 3 weeks of each supplementation protocol, each participant then performed an acute resistance exercise challenge of 4 sets of 15 repetitions of squat/leg press at 50% 1-repetition maximum and continued supplementation over the recovery period that was evaluated. Blood samples were obtained at preexercise and at 0, 15, 30, and 120 minutes postexercise during the acute resistance exercise challenge and during 4 recovery days as well. Two grams of l-carnitine supplementation had positive effects and significantly (P < or = .05) attenuated biochemical markers of purine metabolism (ie, hypoxanthine, xanthine oxidase), free radical formation (malondialdehyde), muscle tissue disruption (myoglobin, creatine kinase), and muscle soreness after physical exertion. However, markers of physical performance (ie, strength, power, get up and go) were not affected by supplementation. These findings support our previous findings of l-carnitine in younger people that such supplementation can reduce chemical damage to tissues after exercise and optimize the processes of muscle tissue repair and remodeling.


Assuntos
Carnitina/análogos & derivados , Esforço Físico , Tartaratos/administração & dosagem , Adulto , Biomarcadores , Carnitina/administração & dosagem , Carnitina/sangue , Estudos Cross-Over , Suplementos Nutricionais , Método Duplo-Cego , Feminino , Radicais Livres , Humanos , Ácido Láctico/sangue , Masculino , Pessoa de Meia-Idade , Mioglobina/sangue , Purinas/metabolismo , Xantina Oxidase/sangue
6.
Curr Sports Med Rep ; 7(4): 218-23, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18607224

RESUMO

Carnitine (L-3-hydroxytrimethylamminobutanoate) is a naturally occurring compound that can be synthesized in mammals from the essential amino acids lysine and methionine or ingested through diet. Primary sources of dietary carnitine are red meat and dairy products; however, commercially produced supplements also are available and have been shown to be safe in humans. Carnitine is stored primarily in skeletal muscle, with lower concentrations in plasma. Biologically, carnitine is essential for the transport of long-chain (carbon chain length = 10) fatty acids across the outer- and inner-mitochondrial membranes (carnitine palmitoyltransferanse I and II, respectively). Conflicting results characterized the early research focused on L-carnitine supplementation's ability to enhance endurance performance, and studies showed no changes occurred in muscle carnitine levels. Nevertheless, promising findings for its use have been observed for various pathologies, including cardiovascular diseases, which show it might mitigate some negative effects and enhance physical function. Recent studies have focused upon a different paradigm for L-carnitine in regulating hypoxic stress and enhancing recovery from exercise.


Assuntos
Carnitina/administração & dosagem , Suplementos Nutricionais , Exercício Físico/fisiologia , Carnitina/metabolismo , Humanos , Metabolismo dos Lipídeos , Músculo Esquelético/metabolismo
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