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1.
Nutrients ; 15(11)2023 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-37299583

RESUMO

(1) Background: Iron deficiency without anemia (IDWA) is a prevalent health concern in premenopausal women. Oral supplementation of iron may be a viable solution to improve blood-iron status in women; however, the effects of a high-dose iron-supplement regimen have been associated with gastrointestinal side effects. Therefore, the purpose of the present study was to evaluate the effectiveness of a low-dose liquid fermented iron-bisglycinate supplement (LIS) on improving blood-iron status in premenopausal women with IDWA without increasing constipation or gastrointestinal distress. (2) Methods: 85 premenopausal women with IDWA (ferritin < 70 ng/dL and hemoglobin > 11.0 g/dL) took a LIS (27 mg) or a placebo (PLA) for 8 weeks. Blood draws were taken at Wk0 and Wk8 of the study to measure serum-iron markers. In addition, surveys of gastrointestinal distress were administered at Wk0, Wk4, and Wk8 while the profile of mood states (POMS) was surveyed at Wk0 and Wk8. (3) Results: Compared to the placebo, the LIS was able to increase serum ferritin (p = 0.03), total serum iron (p = 0.03), and mean corpuscular volume (p = 0.02), while exhibiting no significant interaction in subjective gastrointestinal distress (p > 0.05). No significant effects were detected for POMS (p > 0.05). (4) Conclusions: Supplementing with LIS appears to improve blood-iron status without causing significant gastrointestinal distress in premenopausal women with IDWA.


Assuntos
Anemia Ferropriva , Anemia , Dispepsia , Gastroenteropatias , Deficiências de Ferro , Humanos , Feminino , Valores de Referência , Ferro , Ferritinas , Hemoglobinas/análise , Anemia Ferropriva/tratamento farmacológico
2.
Nutrients ; 13(10)2021 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-34684429

RESUMO

L-carnitine tartrate has been shown to improve relatively short-term recovery among athletes. However, there is a lack of research on the longer-term effects in the general population. OBJECTIVE: The primary objectives of this randomized double-blind, placebo-controlled trial were to evaluate the effects of daily L-carnitine tartrate supplementation for 5 weeks on recovery and fatigue. METHOD: In this study, eighty participants, 21- to 65-years-old, were recruited. Participants were split into two groups of forty participants each, a placebo, and a L-carnitine Tartrate group. Seventy-three participants completed a maintenance exercise training program that culminated in a high-volume exercise challenge. RESULTS: Compared to placebo, L-carnitine tartrate supplementation was able to improve perceived recovery and soreness (p = 0.021), and lower serum creatine kinase (p = 0.016). In addition, L-carnitine tartrate supplementation was able to blunt declines in strength and power compared to placebo following an exercise challenge. Two sub-analyses indicated that these results were independent of gender and age. Interestingly, serum superoxide dismutase levels increased significantly among those supplementing with L-carnitine tartrate. CONCLUSIONS: These findings agree with previous observations among healthy adult subjects and demonstrate that L-carnitine tartrate supplementation beyond 35 days is beneficial for improving recovery and reducing fatigue following exercise across gender and age.


Assuntos
Carnitina/administração & dosagem , Suplementos Nutricionais , Exercício Físico , Fadiga/reabilitação , Tartaratos/administração & dosagem , Adulto , Fatores Etários , Biomarcadores/sangue , Biomarcadores/metabolismo , Composição Corporal , Fadiga/metabolismo , Feminino , Humanos , Masculino , Força Muscular , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Fatores Sexuais , Superóxido Dismutase/sangue , Superóxido Dismutase/metabolismo
3.
Nutrients ; 13(3)2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33807731

RESUMO

The ketogenic diet is a high-fat, very low-carbohydrate, moderate-protein diet that will induce a state of ketosis, but because of its restrictive nature, it may be difficult to adhere to, especially in adolescents. Supplementing with exogenous beta-hydroxybutyrate salts may induce a state of temporary ketosis without any undesirable side effects, thereby promoting the benefits of ketosis and minimizing adherence requirements to a ketogenic diet. To date, beta-hydroxybutyrate supplementation in healthy adolescents has not been explored. Therefore, the purpose of this study was to examine the safety of exogenous beta-hydroxybutyrate salt supplementation in a healthy adolescent population. In the present study, 22 healthy male and female adolescents consumed 3.75 g of beta-hydroxybutyrate salts or maltodextrin placebo twice daily for 90 days. Comprehensive blood safety analysis, bone densitometry, happiness and emotional intelligence surveys, and blood pressure were assessed at Pre, Day 45, and Day 90. There were no significant differences detected in subjects supplementing with beta-hydroxybutyrate salts, indicating that exogenous beta-hydroxybutyrate salts had no detrimental impact on fasting blood safety metrics, bone density, happiness, emotional intelligence, or blood pressure. We conclude that supplementing with exogenous beta-hydroxybutyrate salts is safe and well-tolerated by healthy adolescents.


Assuntos
Ácido 3-Hidroxibutírico/administração & dosagem , Dieta Cetogênica/métodos , Suplementos Nutricionais , Adolescente , Jejum/sangue , Feminino , Voluntários Saudáveis , Humanos , Cetose/sangue , Masculino , Polissacarídeos/administração & dosagem
4.
Nutr Metab Insights ; 13: 1178638820949239, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33061414

RESUMO

BACKGROUND: Muscle mass is an important determinant of metabolic health and physical function. It has previously been demonstrated that the postprandial rise in circulating essential amino acids acts as the main stimulus for muscle protein synthesis (MPS). The current study investigated the postprandial plasma essential amino acid (EAA) and branched-chain amino acid (BCAA) responses of (1) Hydrolyzed whey protein isolate (HWPI) compared to plasma treated non-hydrolyzed whey protein isolate (PT-NHWPI), (2) standard branch-chain amino acids (S-BCAA) compared to plasma treated branch-chained amino acids (PT-BCAA), (3) standard pea protein (S-PP), compared to plasma treated pea protein (PT-PP), and (4) HWPI compared to PT-PP. METHODS: Ten subjects (24.6 ± 5.3 years; 178.8 ± 8.1 cm; 78.6 ± 10.1 kg) participated in a double-blind, randomized, crossover trial comparing four separate protein conditions (HWPI, PT-NHWPI, S-PP, PT-PP). A separate cohort of ten subjects (26.4 ± 7.4 years; 178.8 ± 5.9 cm; 85 ± 12.3 kg) participated in a double-blind randomized, crossover trial comparing two branch-chain amino acid conditions: S-BCAA and PT-BCAA. All conditions were administered following a 7-day washout. Plasma EAA and BCAA concentrations were assessed from blood donated by subjects at pre-consumption, 30-, 60-, 90-, 120-, and 180 minutes post-consumption. RESULTS: Blood plasma levels of total EAA and BCAA concentration were significantly greater in all treated conditions at 30-, 60-, 90-, and 120 minutes post consumption (P < .05). There were no differences between PT-PP and HWPI. DISCUSSION: All proteins significantly elevated EAAs, and BCAAs from basal levels. However, we conclude that the consumption of the treated proteins significantly raises blood levels of EAAs, and BCAAs to a greater extent across multiple dairy, vegan, and isolated BCAA conditions. Moreover, atmospheric plasma treatment of a vegan protein source makes its amino acid response similar to whey. Thus, protein supplementation with that has undergone Ingredient Optimized® atmospheric plasma treatment technology may be highly beneficial for improving the blood plasma amino acid response.

5.
Nutrients ; 12(7)2020 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-32635494

RESUMO

The purpose of this study was to investigate the impact of antioxidant-rich marine phytoplankton supplementation (Oceanix, OCX) on performance and muscle damage following a cross-training event in endurance-trained subjects. Additionally, an animal model was carried out to assess the effects of varying dosages of OCX, with exercise, on intramuscular antioxidant capacity. METHODS: In the human trial, endurance-trained subjects (average running distance = 29.5 ± 2.6 miles × week-1) were randomly divided into placebo (PLA) and OCX (25 mg) conditions for 14 days. The subjects were pre-tested on a one-mile uphill run, maximal isometric strength, countermovement jump (CMJ) and squat jump (SJ) power, and for muscle damage (creatine kinase (CK)). On Day 12, the subjects underwent a strenuous cross-training event. Measures were reassessed on Day 13 and 14 (24 h and 48 h Post event). In the animal model, Wistar rats were divided into four groups (n = 7): (i) Control (no exercise and placebo (CON)), (ii) Exercise (E), (iii) Exercise + OCX 1 (Oceanix, 2.55 mg/day, (iv) Exercise + OCX 2 (5.1 mg/day). The rats performed treadmill exercise five days a week for 6 weeks. Intramuscular antioxidant capacity (superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px)) and muscle damage (CK and myoglobin (MYOB) were collected. The data were analyzed using repeated measures ANOVA and t-test for select variables. The alpha value was set at p < 0.05. RESULTS: For the human trial, SJ power lowered in PLA relative to OCX at 24 h Post (-15%, p < 0.05). Decrements in isometric strength from Pre to 48 h Post were greater in the PLA group (-12%, p < 0.05) than in the OCX. Serum CK levels were greater in the PLA compared to the OCX (+14%, p < 0.05). For the animal trial, the intramuscular antioxidant capacity was increased in a general dose-dependent manner (E + Oc2 > E + Oc1 > E > CON). Additionally, CK and MYOB were lower in supplemented compared to E alone. CONCLUSIONS: Phytoplankton supplementation (Oceanix) sustains performance and lowers muscle damage across repeated exercise bouts. The ingredient appears to operate through an elevating oxidative capacity in skeletal muscle.


Assuntos
Antioxidantes/administração & dosagem , Suplementos Nutricionais , Treino Aeróbico/métodos , Músculo Esquelético/efeitos dos fármacos , Condicionamento Físico Animal/fisiologia , Fitoplâncton , Adulto , Animais , Antioxidantes/metabolismo , Catalase/metabolismo , Creatina Quinase/sangue , Relação Dose-Resposta a Droga , Exercício Físico/fisiologia , Feminino , Glutationa Peroxidase/metabolismo , Humanos , Contração Isométrica/efeitos dos fármacos , Masculino , Doenças Musculares/etiologia , Doenças Musculares/prevenção & controle , Mioglobina/metabolismo , Desempenho Físico Funcional , Ratos , Ratos Wistar , Superóxido Dismutase/metabolismo
6.
Eur J Nutr ; 57(3): 929-938, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28204880

RESUMO

PURPOSE: The optimal health benefits of curcumin are limited by its low solubility in water and corresponding poor intestinal absorption. Cyclodextrins (CD) can form inclusion complexes on a molecular basis with lipophilic compounds, thereby improving aqueous solubility, dispersibility, and absorption. In this study, we investigated the bioavailability of a new γ-cyclodextrin curcumin formulation (CW8). This formulation was compared to a standardized unformulated curcumin extract (StdC) and two commercially available formulations with purported increased bioavailability: a curcumin phytosome formulation (CSL) and a formulation of curcumin with essential oils of turmeric extracted from the rhizome (CEO). METHODS: Twelve healthy human volunteers participated in a double-blinded, cross-over study. The plasma concentrations of the individual curcuminoids that are present in turmeric (namely curcumin, demethoxycurcumin, and bisdemethoxycurcumin) were determined at baseline and at various intervals after oral administration over a 12-h period. RESULTS: CW8 showed the highest plasma concentrations of curcumin, demethoxycurcumin, and total curcuminoids, whereas CSL administration resulted in the highest levels of bisdemethoxycurcumin. CW8 (39-fold) showed significantly increased relative bioavailability of total curcuminoids (AUC0-12) in comparison with the unformulated StdC. CONCLUSION: The data presented suggest that γ-cyclodextrin curcumin formulation (CW8) significantly improves the absorption of curcuminoids in healthy humans.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Antioxidantes/administração & dosagem , Curcumina/administração & dosagem , Suplementos Nutricionais , Aditivos Alimentares/química , Absorção Intestinal , gama-Ciclodextrinas/química , Adulto , Antineoplásicos Fitogênicos/sangue , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/metabolismo , Antioxidantes/análise , Antioxidantes/química , Antioxidantes/metabolismo , Área Sob a Curva , Estudos de Coortes , Estudos Cross-Over , Curcumina/análogos & derivados , Curcumina/análise , Curcumina/química , Curcumina/metabolismo , Diarileptanoides , Método Duplo-Cego , Feminino , Manipulação de Alimentos , Humanos , Masculino , Valor Nutritivo , Adulto Jovem
7.
J Strength Cond Res ; 32(8): 2233-2242, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28399016

RESUMO

Sharp, MH, Lowery, RP, Shields, KA, Lane, JR, Gray, JL, Partl, JM, Hayes, DW, Wilson, GJ, Hollmer, CA, Minivich, JR, and Wilson, JM. The effects of beef, chicken, or whey protein after workout on body composition and muscle performance. J Strength Cond Res 32(8): 2233-2242, 2018-The purpose of this study was to determine the effects of postworkout consumption of beef protein isolate (Beef), hydrolyzed chicken protein (Chx), or whey protein concentrate (WPC), compared with a control on body composition and muscle performance during 8 weeks of resistance training. Forty-one men and women were randomized into 4 groups: WPC (m = 5, f = 5; age [years] = 19 ± 2, height [cm] = 171 ± 10, mass [kg] = 74.60 ± 14.19), Beef (m = 5, f = 5; age [years] = 22 ± 4, height [cm] = 170 ± 7, mass [kg] = 70.13 ± 8.16), Chx (m = 5, f = 6; Age [years] = 21 ± 2, height [cm] = 169 ± 9, mass [kg] = 74.52 ± 13.83), and Maltodextrin (control) (m = 4, f = 6; age [years] = 21 ± 2, height [cm] = 170 ± 9, mass [kg] = 73.18 ± 10.96). Subjects partook in an 8-week periodized resistance training program. Forty-six grams of protein or a control were consumed immediately after training or at similar times on off-days. Dual-energy x-ray absorptiometry was used to determine changes in body composition. Maximum strength was assessed by 1 repetition maximum for bench press (upper body) and deadlift (lower body). Power output was measured using cycle ergometer. Whey protein concentrate (52.48 ± 11.15 to 54.96 ± 11.85 kg), Beef (51.68 ± 7.61 to 54.65 ± 8.67 kg), and Chx (52.97 ± 12.12 to 54.89 ± 13.43 kg) each led to a significant increase in lean body mass compared with baseline (p < 0.0001), whereas the control condition did not (53.14 ± 11.35 to 54.19 ± 10.74 kg). Fat loss was also significantly decreased at 8 weeks compared to baseline for all protein sources (p < 0.0001; WPC: 18.70 ± 7.38 to 17.16 ± 7.18 kg; Beef: 16.43 ± 5.71 to 14.65 ± 5.41 kg; Chx: 17.58 ± 5.57 to 15.87 ± 6.07 kg), but not the control condition (16.29 ± 7.14 to 14.95 ± 7.72 kg). One repetition maximum for both deadlift and bench press was significantly increased for all treatment groups when compared with baseline. No differences in strength were noted between conditions. Overall, the results of this study demonstrate that consuming quality sources of protein from meat or WPC lead to significant benefits in body composition compared with control.


Assuntos
Composição Corporal/efeitos dos fármacos , Suplementos Nutricionais , Força Muscular , Treinamento Resistido , Proteínas do Soro do Leite/farmacologia , Absorciometria de Fóton , Adolescente , Adulto , Animais , Bovinos , Galinhas , Método Duplo-Cego , Feminino , Humanos , Masculino , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/fisiologia , Polissacarídeos/farmacologia , Carne Vermelha , Adulto Jovem
8.
J Am Coll Nutr ; 36(3): 177-183, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28080323

RESUMO

OBJECTIVE: Oral adenosine-5'-triphosphate (ATP) administration has failed to increase plasma ATP levels; however, chronic supplementation with ATP has shown to increase power, strength, lean body mass, and blood flow in trained athletes. The purpose of this study was to investigate the effects of ATP supplementation on postexercise ATP levels and on muscle activation and excitability and power following a repeated sprint bout. METHODS: In a double-blind, placebo-controlled, randomized design, 42 healthy male individuals were given either 400 mg of ATP as disodium salt or placebo for 2 weeks prior to an exercise bout. During the exercise bout, muscle activation and excitability (ME, ratio of power output to muscle activation) and Wingate test peak power were measured during all sprints. ATP and metabolites were measured at baseline, after supplementation, and immediately following exercise. RESULTS: Oral ATP supplementation prevented a drop in ATP, adenosine-5'-diphosphate (ADP), and adenosine-5'-monophosphate (AMP) levels postexercise (p < 0.05). No group by time interaction was observed for muscle activation. Following the supplementation period, muscle excitability significantly decreased in later bouts 8, 9, and 10 in the placebo group (-30.5, -28.3, and -27.9%, respectively; p < 0.02), whereas ATP supplementation prevented the decline in later bouts. ATP significantly increased Wingate peak power in later bouts compared to baseline (bout 8: +18.3%, bout 10: +16.3%). CONCLUSIONS: Oral ATP administration prevents exercise-induced declines in ATP and its metabolite and enhances peak power and muscular excitability, which may be beneficial for sports requiring repeated high-intensity sprinting bouts.


Assuntos
Trifosfato de Adenosina/farmacologia , Desempenho Atlético , Exercício Físico , Músculo Esquelético/efeitos dos fármacos , Trifosfato de Adenosina/administração & dosagem , Administração Oral , Adolescente , Método Duplo-Cego , Humanos , Masculino , Músculo Esquelético/fisiologia , Adulto Jovem
9.
J Am Coll Nutr ; 35(8): 679-691, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27333407

RESUMO

OBJECTIVE: The purpose of this study was to investigate the effects of Fortetropin on skeletal muscle growth and strength in resistance-trained individuals and to investigate the anabolic and catabolic signaling effects using human and rodent models. METHODS: In the rodent model, male Wistar rats (250 g) were gavage fed with either 1.2 ml of tap water control (CTL) or 0.26 g Fortetropin for 8 days. Then rats participated in a unilateral plantarflexion exercise bout. Nonexercised and exercised limbs were harvested at 180 minutes following and analyzed for gene and protein expression relative to mammalian target of rapamycin (mTOR) and ubiquitin signaling. For the human model, 45 (of whom 37 completed the study), resistance-trained college-aged males were divided equally into 3 groups receiving a placebo macronutrient matched control, 6.6 or 19.8 g of Fortetropin supplementation during 12 weeks of resistance training. Lean mass, muscle thickness, and lower and upper body strength were measured before and after 12 weeks of training. RESULTS: The human study results indicated a Group × Time effect (p ≤ 0.05) for lean mass in which the 6.6 g (+1.7 kg) and 19.8 g (+1.68 kg) but not placebo (+0.6 kg) groups increased lean mass. Similarly, there was a Group × Time effect for muscle thickness (p ≤ 0.05), which increased in the experimental groups only. All groups increased equally in bench press and leg press strength. In the rodent model, a main effect for exercise (p ≤ 0.05) in which the control plus exercise but not Fortetropin plus exercise increased both ubiquitin monomer protein expression and polyubiquitination. mTOR signaling was elevated to a greater extent in the Fortetropin exercising conditions as indicated by greater phosphorylation status of 4EBP1, rp6, and p70S6K for both exercising conditions. CONCLUSIONS: Fortetropin supplementation increases lean body mass (LBM) and decreases markers of protein breakdown while simultaneously increasing mTOR signaling.


Assuntos
Composição Corporal/efeitos dos fármacos , Força Muscular/efeitos dos fármacos , Proteolipídeos/administração & dosagem , Adolescente , Animais , Dieta , Suplementos Nutricionais , Humanos , Masculino , Músculo Esquelético/efeitos dos fármacos , Miostatina/sangue , Placebos , Ratos , Ratos Wistar , Treinamento Resistido , Transdução de Sinais , Serina-Treonina Quinases TOR/fisiologia , Ubiquitina/fisiologia , Adulto Jovem
10.
PLoS One ; 11(5): e0155153, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27182886

RESUMO

BACKGROUND: The primary purpose of this investigation was to examine the effects of arachidonic acid (ARA) supplementation on functional performance and body composition in trained males. In addition, we performed a secondary study looking at molecular responses of ARA supplementation following an acute exercise bout in rodents. METHODS: Thirty strength-trained males (age: 20.4 ± 2.1 yrs) were randomly divided into two groups: ARA or placebo (i.e. CTL). Then, both groups underwent an 8-week, 3-day per week, non-periodized training protocol. Quadriceps muscle thickness, whole-body composition scan (DEXA), muscle strength, and power were assessed at baseline and post-test. In the rodent model, male Wistar rats (~250 g, ~8 weeks old) were pre-fed with either ARA or water (CTL) for 8 days and were fed the final dose of ARA prior to being acutely strength trained via electrical stimulation on unilateral plantar flexions. A mixed muscle sample was removed from the exercised and non-exercised leg 3 hours post-exercise. RESULTS: Lean body mass (2.9%, p<0.0005), upper-body strength (8.7%, p<0.0001), and peak power (12.7%, p<0.0001) increased only in the ARA group. For the animal trial, GSK-ß (Ser9) phosphorylation (p<0.001) independent of exercise and AMPK phosphorylation after exercise (p-AMPK less in ARA, p = 0.041) were different in ARA-fed versus CTL rats. CONCLUSIONS: Our findings suggest that ARA supplementation can positively augment strength-training induced adaptations in resistance-trained males. However, chronic studies at the molecular level are required to further elucidate how ARA combined with strength training affect muscle adaptation.


Assuntos
Adaptação Fisiológica/efeitos dos fármacos , Ácidos Araquidônicos/farmacologia , Composição Corporal/efeitos dos fármacos , Suplementos Nutricionais , Metabolismo Energético/efeitos dos fármacos , Fenômenos Fisiológicos Musculoesqueléticos/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Adolescente , Adulto , Ração Animal , Animais , Composição Corporal/genética , Metabolismo Energético/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Modelos Animais , Desenvolvimento Muscular/efeitos dos fármacos , Desenvolvimento Muscular/genética , Força Muscular/efeitos dos fármacos , Fosfoproteínas/metabolismo , Condicionamento Físico Animal , Biossíntese de Proteínas , Proteômica/métodos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Treinamento Resistido , Serina-Treonina Quinases TOR/metabolismo , Adulto Jovem
11.
Sports Med ; 46(10): 1407-18, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27071990

RESUMO

Many sports involve repeated bouts of high-intensity exercise. High-intensity exercise is compromised, however, by the early onset of exercise-induced fatigue. Metabolic by-products, ion dysbalance and amount of phosphocreatine are considered the main peripheral causes of fatigue during high-intensity exercise. Intake of nutritional ergogenic aids is commonplace to enhance performance of high-intensity exercise by offsetting the potential mechanisms of fatigue. Creatine, probably one of the best known nutritional aids to enhance performance of high-intensity exercise, has convincingly substantiated its ergogenic potential. Although multi-ingredient supplements are now common, the justification for effectiveness is mostly based on observations with single intake of those ingredients. In this narrative review, the main focus is on the evidence of the effect of co-ingestion of ergogenic aids on performance of high intensity exercise for which the single intake has shown beneficial effects on high-intensity performance.


Assuntos
Desempenho Atlético/fisiologia , Suplementos Nutricionais , Treinamento Intervalado de Alta Intensidade , Substâncias para Melhoria do Desempenho/administração & dosagem , Cafeína/administração & dosagem , Creatina/administração & dosagem , Metabolismo Energético , Fadiga/prevenção & controle , Humanos , Bicarbonato de Sódio/administração & dosagem , beta-Alanina/administração & dosagem
12.
J Strength Cond Res ; 30(7): 1843-54, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24714541

RESUMO

Lowery, RP, Joy, JM, Rathmacher, JA, Baier, SM, Fuller, JC Jr, Shelley, MC II, Jäger, R, Purpura, M, Wilson, SMC, and Wilson, JM. Interaction of beta-hydroxy-beta-methylbutyrate free acid and adenosine triphosphate on muscle mass, strength, and power in resistance trained individuals. J Strength Cond Res 30(7): 1843-1854, 2016-Adenosine-5'-triphosphate (ATP) supplementation helps maintain performance under high fatiguing contractions and with greater fatigue recovery demands also increase. Current evidence suggests that the free acid form of ß-hydroxy-ß-methylbutyrate (HMB-FA) acts by speeding regenerative capacity of skeletal muscle after high-intensity or prolonged exercise. Therefore, we investigated the effects of 12 weeks of HMB-FA (3 g) and ATP (400 mg) administration on lean body mass (LBM), strength, and power in trained individuals. A 3-phase double-blind, placebo-, and diet-controlled study was conducted. Phases consisted of an 8-week periodized resistance training program (phase 1), followed by a 2-week overreaching cycle (phase 2), and a 2-week taper (phase 3). Lean body mass was increased by a combination of HMB-FA/ATP by 12.7% (p < 0.001). In a similar fashion, strength gains after training were increased in HMB-FA/ATP-supplemented subjects by 23.5% (p < 0.001). Vertical jump and Wingate power were increased in the HMB-FA/ATP-supplemented group compared with the placebo-supplemented group, and the 12-week increases were 21.5 and 23.7%, respectively. During the overreaching cycle, strength and power declined in the placebo group (4.3-5.7%), whereas supplementation with HMB-FA/ATP resulted in continued strength gains (1.3%). In conclusion, HMB-FA and ATP in combination with resistance exercise training enhanced LBM, power, and strength. In addition, HMB-FA plus ATP blunted the typical response to overreaching, resulting in a further increase in strength during that period. It seems that the combination of HMB-FA/ATP could benefit those who continuously train at high levels such as elite athletes or military personnel.


Assuntos
Trifosfato de Adenosina/farmacologia , Composição Corporal/efeitos dos fármacos , Força Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Valeratos/farmacologia , Adulto , Suplementos Nutricionais , Método Duplo-Cego , Interações Medicamentosas , Teste de Esforço , Humanos , Masculino , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/fisiologia , Treinamento Resistido , Ultrassonografia , Adulto Jovem
13.
Eur J Appl Physiol ; 114(6): 1217-27, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24599749

RESUMO

INTRODUCTION: Studies utilizing beta-hydroxy-beta-methylbutyrate (HMB) supplementation in trained populations are limited. No long-term studies utilizing HMB free acid (HMB-FA) have been conducted. Therefore, we investigated the effects of 12 weeks of HMB-FA supplementation on skeletal muscle hypertrophy, body composition, strength, and power in trained individuals. We also determined the effects of HMB-FA on muscle damage and performance during an overreaching cycle. METHODS: A three-phase double-blind, placebo- and diet-controlled randomized intervention study was conducted. Phase 1 was an 8-week-periodized resistance-training program; Phase 2 was a 2-week overreaching cycle; and Phase 3 was a 2-week taper. Muscle mass, strength, and power were examined at weeks 0, 4, 8, and 12 to assess the chronic effects of HMB-FA; and assessment of these, as well as cortisol, testosterone, and creatine kinase (CK) was performed at weeks 9 and 10 of the overreaching cycle. RESULTS: HMB-FA resulted in increased total strength (bench press, squat, and deadlift combined) over the 12-week training (77.1 ± 18.4 vs. 25.3 ± 22.0 kg, p < 0.001); a greater increase in vertical jump power (991 ± 168 vs. 630 ± 167 W, p < 0.001); and increased lean body mass gain (7.4 ± 4.2 vs. 2.1 ± 6.1 kg, p < 0.001) in HMB-FA- and placebo-supplemented groups, respectively. During the overreaching cycle, HMB-FA attenuated increases in CK (-6 ± 91 vs. 277 ± 229 IU/l, p < 0.001) and cortisol (-0.2 ± 2.9 vs. 4.5 ± 1.7 µg/dl, p < 0.003) in the HMB-FA- and placebo-supplemented groups, respectively. CONCLUSIONS: These results suggest that HMB-FA enhances hypertrophy, strength, and power following chronic resistance training, and prevents decrements in performance following the overreaching.


Assuntos
Força Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Treinamento Resistido , Valeratos/farmacologia , Suplementos Nutricionais , Método Duplo-Cego , Humanos , Masculino , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/fisiologia , Valeratos/administração & dosagem , Adulto Jovem
14.
J Int Soc Sports Nutr ; 10(1): 44, 2013 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-24107586

RESUMO

BACKGROUND: Xpand® 2X is a proprietary blend comprised of branched chain amino acids, creatine monohydrate, beta-alanine (CarnoSyn®), quercetin, coenzymated B-vitamins, alanyl-glutamine (Sustamine®), and natural nitrate sources from pomegranate and beet root extracts purported to enhance the neuromuscular adaptations of resistance training. However to date, no long-term studies have been conducted with this supplement. The purpose of this study was to investigate the effects of a multi-ingredient performance supplement (MIPS) on skeletal muscle hypertrophy, lean body mass and lower body strength in resistance-trained males. METHODS: Twenty resistance-trained males (21.3 ± 1.9 years) were randomly assigned to consume a MIPS or a placebo of equal weight and volume (food-grade orange flavors and sweeteners) in a double-blind manner, 30 minutes prior to exercise. All subjects participated in an 8-week, 3-day per week, periodized, resistance-training program that was split-focused on multi-joint movements such as leg press, bench press, and bent-over rows. Ultrasonography measured muscle thickness of the quadriceps, dual-energy X-ray absorptiometry (DEXA) determined lean body mass, and strength of the bench press and leg press were determined at weeks 0, 4, and 8 of the study. Data were analyzed with a 2 × 3 repeated measures ANOVA with LSD post hoc tests utilized to locate differences. RESULTS: There was a significant group-by-time interaction in which the MIPS supplementation resulted in a significant (p < 0.01) increase in strength of the bench press (18.4% vs. 9.6%) compared with placebo after 4 and 8 weeks of training. There were no significant group by time interactions between MIPS supplementation nor the placebo in leg press strength (p = .08). MIPS supplementation also resulted in a significant increase in lean body mass (7.8% vs. 3.6%) and quadriceps muscle thickness (11.8% vs. 4.5%) compared with placebo (group*time, p <0.01). CONCLUSIONS: These results suggest that this MIPS can positively augment adaptations in strength, and skeletal muscle hypertrophy in resistance-trained men.

15.
Nutr J ; 12: 86, 2013 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-23782948

RESUMO

Consumption of moderate amounts of animal-derived protein has been shown to differently influence skeletal muscle hypertrophy during resistance training when compared with nitrogenous and isoenergetic amounts of plant-based protein administered in small to moderate doses. Therefore, the purpose of the study was to determine if the post-exercise consumption of rice protein isolate could increase recovery and elicit adequate changes in body composition compared to equally dosed whey protein isolate if given in large, isocaloric doses.


Assuntos
Composição Corporal , Suplementos Nutricionais , Proteínas do Leite/administração & dosagem , Oryza/química , Proteínas de Plantas/administração & dosagem , Treinamento Resistido , Proteínas Alimentares/administração & dosagem , Método Duplo-Cego , Humanos , Masculino , Músculo Esquelético/metabolismo , Proteínas do Soro do Leite , Adulto Jovem
16.
Br J Nutr ; 110(3): 538-44, 2013 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-23286834

RESUMO

The purpose of the present study was to determine the effects of short-term supplementation with the free acid form of b-hydroxyb-methylbutyrate (HMB-FA) on indices of muscle damage, protein breakdown, recovery and hormone status following a high-volume resistance training session in trained athletes. A total of twenty resistance-trained males were recruited to participate in a high-volume resistance training session centred on full squats, bench presses and dead lifts. Subjects were randomly assigned to receive either 3 g/d of HMB-FA or a placebo. Immediately before the exercise session and 48 h post-exercise, serum creatine kinase (CK), urinary 3-methylhistadine (3-MH), testosterone, cortisol and perceived recovery status (PRS) scale measurements were taken. The results showed that CK increased to a greater extent in the placebo (329%) than in the HMB-FA group (104%) (P»0·004, d » 1·6). There was also a significant change for PRS, which decreased to a greater extent in the placebo (9·1 (SEM 0·4) to 4·6 (SEM 0·5)) than in the HMB-FA group (9·1 (SEM 0·3) to 6·3 (SEM 0·3)) (P»0·005, d » 20·48). Muscle protein breakdown, measured by 3-MH analysis, numerically decreased with HMB-FA supplementation and approached significance (P»0·08, d » 0·12). There were no acute changes in plasma total or free testosterone, cortisol or C-reactive protein. In conclusion, these results suggest that an HMB-FA supplement given to trained athletes before exercise can blunt increases in muscle damage and prevent declines in perceived readiness to train following a high-volume, muscle-damaging resistance-training session.


Assuntos
Suplementos Nutricionais , Exercício Físico/fisiologia , Proteínas Musculares/urina , Doenças Musculares/tratamento farmacológico , Treinamento Resistido , Valeratos/uso terapêutico , Levantamento de Peso/fisiologia , Adulto , Biomarcadores/metabolismo , Creatina Quinase/sangue , Humanos , Masculino , Doenças Musculares/etiologia , Doenças Musculares/metabolismo , Percepção , Descanso , Valeratos/farmacologia , Adulto Jovem
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