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1.
Nutr Res ; 34(5): 442-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24916558

RESUMO

The purpose of this study was to determine the safety and efficacy of consuming a preworkout supplement (SUP) containing caffeine, creatine, ß-alanine, amino acids, and B vitamins for 28 days. We hypothesized that little to no changes in kidney and liver clinical blood markers or resting heart rate and blood pressure (BP) would be observed. In addition, we hypothesized that body composition and performance would improve in recreationally active males after 28 days of supplementation. In a double-blind, placebo-controlled study, participants were randomly assigned to ingest one scoop of either the SUP or placebo every day for 28 days, either 20 minutes before exercise or ad libitum on nonexercise days. Resting heart rate and BP, body composition, and fasting blood samples were collected before and after supplementation. Aerobic capacity as well as muscular strength and endurance were also measured. Significant (P < .05) main effects for time were observed for resting heart rate (presupplementation, 67.59 ± 7.90 beats per minute; postsupplementation, 66.18 ± 7.63 beats per minute), systolic BP (presupplementation, 122.41 ± 11.25 mm Hg; postsupplementation, 118.35 ± 11.58 mm Hg), blood urea nitrogen (presupplementation, 13.12 ± 2.55 mg/dL; postsupplementation, 15.24 ± 4.47 mg/dL), aspartate aminotransferase (presupplementation, 34.29 ± 16.48 IU/L; postsupplementation, 24.76 ± 4.71 IU/L), and alanine aminotransferase (presupplementation, 32.76 ± 19.72 IU/L; postsupplementation, 24.88 ± 9.68 IU/L). Significant main effects for time were observed for body fat percentage (presupplementation, 15.55% ± 5.79%; postsupplementation, 14.21% ± 5.38%; P = .004) and fat-free mass (presupplementation, 70.80 ± 9.21 kg; postsupplementation, 71.98 ± 9.27 kg; P = .006). A significant decrease in maximal oxygen consumption (presupplementation, 47.28 ± 2.69 mL/kg per minute; postsupplementation, 45.60 ± 2.81 mL/kg per minute) and a significant increase in percentage of oxygen consumption per unit time at which ventilatory threshold occurred (presupplementation, 64.38% ± 6.63%; postsupplementation, 70.63% ± 6.39%) and leg press one-repetition maximum (presupplementation, 218.75 ± 38.43 kg; postsupplementation, 228.75 ± 44.79 kg) were observed in the SUP only. No adverse effects were noted for renal and hepatic clinical blood markers, resting heart rate, or BP. Supplements containing similar ingredients and doses should be safe for ingestion periods lasting up to 28 days in healthy, recreationally trained, college-aged men.


Assuntos
Aminoácidos/farmacologia , Cafeína/farmacologia , Suplementos Nutricionais , Exercício Físico/fisiologia , Força Muscular/efeitos dos fármacos , Resistência Física/efeitos dos fármacos , Complexo Vitamínico B/farmacologia , Adolescente , Pressão Sanguínea/efeitos dos fármacos , Nitrogênio da Ureia Sanguínea , Composição Corporal/efeitos dos fármacos , Creatina/farmacologia , Suplementos Nutricionais/efeitos adversos , Método Duplo-Cego , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Consumo de Oxigênio/efeitos dos fármacos , Resistência Física/fisiologia , Recreação , Transaminases/sangue , Resultado do Tratamento , Adulto Jovem , beta-Alanina/farmacologia
2.
Nutr Metab (Lond) ; 9: 28, 2012 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-22463603

RESUMO

BACKGROUND: The purpose of this study was to determine the effects of the pre-workout supplement Assault™ (MusclePharm, Denver, CO, USA) on upper and lower body muscular endurance, aerobic and anaerobic capacity, and choice reaction time in recreationally-trained males. Subjective feelings of energy, fatigue, alertness, and focus were measured to examine associations between psychological factors and human performance. METHODS: Twelve recreationally-trained males participated in a 3-week investigation (mean +/- SD, age: 28 +/- 5 y, height: 178 +/- 9 cm, weight: 79.2 +/- 15.7 kg, VO2max: 45.7 +/- 7.6 ml/kg/min). Subjects reported to the human performance laboratory on three separate occasions. All participants completed a baseline/familiarization day of testing that included a maximal graded exercise test for the determination of aerobic capacity (VO2max), one-rep maximum (1-RM) for bench and leg press to determine 75% of 1-RM, choice reaction tests, and intermittent critical velocity familiarization. Choice reaction tests included the following: single-step audio and visual, one-tower stationary protocol, two-tower lateral protocol, three-tower multi-directional protocol, and three-tower multi-directional protocol with martial arts sticks. Subjects were randomly assigned to ingest either the supplement (SUP) or the placebo (PL) during Visit 2. Subjects were provided with the cross-over treatment on the last testing visit. Testing occurred 20 min following ingestion of both treatments. RESULTS: Significant (p < 0.05) main effects for the SUP were observed for leg press (SUP: 13 ± 6 reps, PL: 11 ± 3 reps), perceived energy (SUP: 3.4 ± 0.9, PL: 3.1 ± 0.8), alertness (SUP: 4.0 ± 0.7, PL: 3.5 ± 0.8), focus (SUP: 4.1 ± 0.6, PL: 3.5 ± 0.8), choice reaction audio single-step (SUP: 0.92 ± 0.10 s, PL: 0.97 ± 0.11 s), choice reaction multi-direction 15 s (SUP: 1.07 ± 0.12 s, PL: 1.13 ± 0.14 s), and multi-direction for 30 s (SUP: 1.10 ± 0.11 s, PL: 1.14 ± 0.13 s). CONCLUSIONS: Ingesting the SUP before exercise significantly improved agility choice reaction performance and lower body muscular endurance, while increasing perceived energy and reducing subjective fatigue. These findings suggest that the SUP may delay fatigue during strenuous exercise.

3.
J Strength Cond Res ; 25(3): 652-61, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21273906

RESUMO

Both load cell and mechanical scale-based hydrostatic weighing (HW) systems are used for the measurement of underwater weight. However, there has been no direct comparison of the 2 methods. The purpose of the current investigation was to simultaneously compare a load cell and mechanical scale for use in HW. Twenty-seven men and women (mean ± SD, age: 22 ± 2 years) participated in the 2-day investigation. Each subject completed 2 HW assessments 24 hours apart. Single-day comparisons of all trials for both days revealed no significant difference between the mechanical scale and the load cell (mean difference < 0.016 kg, p > 0.05). True underwater weight values were not significantly different between methods for either days (mean difference < 0.014 kg, p > 0.05) and accounted for a mean difference in percent fat (%FAT) of <0.108%. The 95% limits of agreement indicated a maximum difference between methods of 0.53% FAT. Both methods produced similar reliability SEM values (mechanical SEM < 0.72%FAT, load cell SEM < 0.75%FAT). In conclusion, there was no difference between mechanical scale and load cell measurements of underwater weights and the added precision of the load cell only marginally (<0.16%FAT) improved day-to-day reliability. Either a mechanical scale or load cell can be used for HW with similar accuracy and reliability in young adults with a body mass index of 18.7-34.4 (5-25%FAT).


Assuntos
Composição Corporal/fisiologia , Peso Corporal/fisiologia , Pesos e Medidas Corporais/métodos , Adulto , Feminino , Humanos , Imersão , Masculino , Reprodutibilidade dos Testes , Adulto Jovem
4.
J Acoust Soc Am ; 122(4): 2413-24, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17902875

RESUMO

Several experiments have been performed to investigate the mechanical vibrations associated with an organ pipe. The measurements have been made by using laser Doppler vibrometry, a well-known not-invasive optical measurement technique that is very widely used in structural dynamics. The recorded signals are analyzed by using a well-established decomposition method in time domain, i.e., independent component analysis. Asymptotic dynamics methods to recognize low-dimensional dynamic system associated with this wave field is then considered. The full-toned recorded signals appear decomposed into three independent components. The independent components are nonlinear due to the fractal dimension of the attractor. These results for the mechanic vibrational field are compared with those of the acoustic one. It is interesting to note that the two fields have many common characteristics. Finally, a low-dimensional dynamic system that reproduces the main characteristics of the mechanical wave field in the time and frequency domains is introduced.

5.
Syst Appl Microbiol ; 30(1): 31-8, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16621401

RESUMO

The taxomony of strain CRSS (DSM 15686(T)=ATCC BAA-848(T)) isolated from Cape Russell in Antarctica (Ross Sea, 74 52.35 S 163 53.03 E) was investigated in a polyphasic approach. The morphological, physiological and genetic characteristics were compared with that of related species of the genus Halomonas. The isolate grew optimally at pH 9.0, 10% NaCl at 30 degrees C. The cells were Gram-negative aerobic rods able to produce exopolysaccharide. They accumulated glycine-betaine, as a major osmolyte, with minor components ectoine and glutamate. The strain CRSS biosynthetised alpha-glucosidase. The polar lipid profile consisted of phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol as major components. Ubiquinone with nine repetitive unities (Q9) was the only quinone found and the fatty acid composition was dominated by C18:1 (53%). The G+C content of DNA was 55.0mol% and its phylogenetic position was established by 16S rRNA gene sequencing as a member of the genus Halomonas. For physiological, chemotaxonomic and genetic features (DNA-DNA hybridisation) it is proposed to classify the isolate as a new species for which we propose the name Halomonas alkaliantarctica sp. nov.


Assuntos
Sedimentos Geológicos/microbiologia , Halomonas/classificação , Halomonas/fisiologia , Polissacarídeos Bacterianos/metabolismo , Regiões Antárticas , Composição de Bases , Biodiversidade , DNA Bacteriano/química , DNA Ribossômico/genética , Genes de RNAr , Halomonas/química , Halomonas/isolamento & purificação , Concentração de Íons de Hidrogênio , Lipídeos/análise , Dados de Sequência Molecular , Filogenia , RNA Ribossômico 16S/genética , Cloreto de Sódio/metabolismo
6.
Syst Appl Microbiol ; 29(4): 300-7, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16682297

RESUMO

A new thermophilic spore-forming strain MR3CT was isolated from geothermal soil located on Mount Rittmann in Antarctica. Strain MR3CT was Gram-positive, rod-shaped, occurring in pairs or filamentous. Growth was observed between 45 and 65 degrees C (optimum 61 degrees C) and at pH 5.0-6.5 (optimum pH 5.6). It was capable of utilizing galactose, trehalose, maltose and sucrose. The microorganism produced an exopolysaccharide and synthesized an extracellular constitutive amylolytic activity. The G + C content of DNA was 43.5 mol%. On the basis of 16S rRNA gene sequence similarity, strain MR3CT was shown to be related most closely to Anoxybacillus species. Chemotaxonomic data (major isoprenoid quinone-menaquinone-7; major fatty acid-iso-C15:0 and iso-C17:0) supported the affiliation of strain MR3C1T to the genus Anoxybacillus. The results of DNA-DNA hybridization, physiological and biochemical tests allowed genotypic and phenotypic differentiation of strain MR3CT from the validly published Anoxybacillus species. MR3CT therefore represents a new species, for which the name Anoxybacillus amylolyticus sp. nov., is proposed, with the type strain MR3CT (= ATCC BAA-872T = DSM 15939T = CIP 108338T).


Assuntos
Amilases/biossíntese , Bactérias Gram-Positivas/classificação , Bactérias Gram-Positivas/isolamento & purificação , Microbiologia do Solo , Regiões Antárticas , Composição de Bases , Metabolismo dos Carboidratos , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Ácidos Graxos/análise , Ácidos Graxos/isolamento & purificação , Genes de RNAr/genética , Bactérias Gram-Positivas/citologia , Bactérias Gram-Positivas/fisiologia , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Dados de Sequência Molecular , Filogenia , Polissacarídeos Bacterianos/biossíntese , Quinonas/análise , Quinonas/isolamento & purificação , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Temperatura , Terpenos/análise
7.
Biotechnol Lett ; 26(21): 1635-8, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15604811

RESUMO

A haloalkalophilic Halomonas strain CRSS, isolated from salt sediments in Antarctica, produced exocellular polysaccharides (EPS) up to 2.9 g g(-1) dry cells. Acetate was the most efficient carbon source for EPS production. The composition of media strongly affected the nature of the polymers; a mannan and a xylo-mannan, were obtained when cells were grown on complex media. Acetate was the most efficient carbon source for EPS production and in presence of this substrate, a new polysaccharide, a fructo-glucan, was produced. The EPS fraction was composed by glucose, fructose, glucosamine and galactosamine in relative proportions of 1:0.7:0.3:trace.


Assuntos
Técnicas de Cultura de Células/métodos , Meios de Cultura/química , Meios de Cultura/metabolismo , Halomonas/classificação , Halomonas/metabolismo , Polissacarídeos Bacterianos/biossíntese , Polissacarídeos Bacterianos/química , Microbiologia da Água , Regiões Antárticas , Halomonas/crescimento & desenvolvimento , Biologia Marinha , Polissacarídeos Bacterianos/análise , Especificidade da Espécie
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