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1.
J Food Sci Technol ; 59(2): 589-596, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35153308

RESUMO

The purpose of this study was to evaluate the controlled-release properties of nutrients from coconut water-based hydrogel. Hydrogels were prepared at varying proportions of gellan and xanthan gums such that the total weight of the gelling agents for all 11 formulations was 1% (w/w) in coconut water. The formulation of the hydrogel was selected using gravimetric analysis by evaluating the dissolution weight of the hydrogel in simulated gastric fluid and simulated intestinal fluid. Interestingly, hydrogel with 0.7% gellan gum and 0.3% xanthan gum showed the most tolerance towards simulated gastric and intestinal fluids over a 1-h period. The in-vitro release study was performed in simulated gastric fluid and followed by simulated intestinal fluid for about 2 h. The trend of release profile showed that the hydrogel had the ability to sustain the nutrients release over a period of 1 h. After 75 min, the release trend was static indicated the nutrients was released from the hydrogel. In conclusion, a coconut water-based hydrogel formulated with 0.7% of gellan and 0.3% of xanthan gum has demonstrated its controlled-release property as evidenced by its effectiveness in the sustained release of nutrients over a period of 1 h.

2.
Appl Physiol Nutr Metab ; 45(5): 513-519, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31675478

RESUMO

There is emerging evidence that hydrogen-rich water (H2-water) has beneficial effects on the physiological responses to exercise. However, few studies investigate its ergogenic potential. This randomized controlled trial examined the effects of H2-water ingestion on physiological responses and exercise performance during incremental treadmill running. In a double-blind crossover design, 14 endurance-trained male runners (age, 34 ± 4 years; body mass, 63.1 ± 7.2 kg; height, 1.72 ± 0.05 m) were randomly assigned to ingest 2 doses of 290-mL H2-water or placebo on each occasion. The first bolus was given before six 4-min submaximal running bouts, and the second bolus was consumed before the maximal incremental running test. Expired gas, heart rate (HR), and ratings of perceived exertion (RPE) were recorded; blood samples were collected at the end of each submaximal stage and post maximal running test. Cardiorespiratory responses, RPE, and blood gas indices were not significantly different at each submaximal running intensity (range: 34%-91% maximal oxygen uptake) between H2-water and placebo trials. No statistical difference was observed in running time to exhaustion (618 ± 126 vs. 619 ± 113 s), maximal oxygen uptake (56.9 ± 4.4 vs. 57.1 ± 4.7 mL·kg-1·min-1), maximal HR (184 ± 7 vs. 184 ± 7 beat·min-1), and RPE (19 ± 1 vs. 19 ± 1) in the runners between the trials. The results suggest that the ingestion of 290 mL of H2-water before submaximal treadmill running and an additional dose before the subsequent incremental running to exhaustion were not sufficiently ergogenic in endurance-trained athletes. Novelty Acute ingestion of H2-water does not seem to be ergogenic for endurance performance. A small dose of H2-water does not modulate buffering capacity during intense endurance exercise in athletes.


Assuntos
Água Potável/química , Teste de Esforço , Corrida , Adulto , Método Duplo-Cego , Treino Aeróbico , Frequência Cardíaca/fisiologia , Humanos , Hidrogênio/farmacologia , Masculino
3.
Eur J Appl Physiol ; 119(8): 1711-1723, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31098832

RESUMO

PURPOSE: To examine the effect of carbohydrate (CHO) mouth rinsing on endurance running responses and performance in dehydrated individuals. METHODS: In a double blind, randomised crossover design, 12 well-trained male runners completed 4 running time to exhaustion (TTE) trials at a speed equivalent to 70% of VO2peak in a thermoneutral condition. Throughout each run, participants mouth rinsed and expectorated every 15 min either 25 mL of 6% CHO or a placebo (PLA) solution for 10 s. The four TTEs consisted of two trials in the euhydrated (EU-CHO and EU-PLA) and two trials in the dehydrated (DY-CHO and DY-PLA) state. Prior to each TTE run, participants were dehydrated via exercise and allowed a passive rest period during which they were fed and either rehydrated equivalent to their body mass deficit (i.e., EU trials) or ingested only 50 mL of water (DY trials). RESULTS: CHO mouth rinsing significantly improved TTE performance in the DY compared to the EU trials (78.2 ± 4.3 vs. 76.9 ± 3.8 min, P = 0.02). The arousal level of the runners was significantly higher in the DY compared to the EU trials (P = 0.02). There was no significant difference among trials in heart rate, plasma glucose and lactate, and psychological measures. CONCLUSIONS: CHO mouth rinsing enhanced running performance significantly more when participants were dehydrated vs. euhydrated due to the greater sensitivity of oral receptors related to thirst and central mediated activation. These results show that level of dehydration alters the effect of brain perception with presence of CHO.


Assuntos
Carboidratos/uso terapêutico , Desidratação/tratamento farmacológico , Tolerância ao Exercício , Antissépticos Bucais/uso terapêutico , Corrida , Adulto , Limiar Anaeróbio , Carboidratos/administração & dosagem , Desidratação/prevenção & controle , Humanos , Masculino , Antissépticos Bucais/administração & dosagem , Estado de Hidratação do Organismo
4.
J Med Food ; 22(1): 1-13, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30592688

RESUMO

Aging is an inevitable and ubiquitous progress that affects all living organisms. A total of 18 strains of lactic acid bacteria (LAB) were evaluated on the activation of adenosine monophosphate-activated protein kinase (AMPK), an intracellular energy sensor mediating lifespan extension. The cell-free supernatant (CFS) of Lactobacillus fermentum DR9 (LF-DR9), Lactobacillus paracasei OFS 0291 (LP-0291), and Lactobacillus helveticus OFS 1515 (LH-1515) showed the highest activation of AMPK and was further evaluated. The phosphorylation of AMPK by these three LAB strains was more evident in U2OS and C2C12 cells, compared to the other cell lines and control (P < .05). Using premature senescent Sprague-Dawley rats induced by D-galactose (D-gal), the administration of LAB (10 log CFU/rat/day) for 12 weeks prevented the shortening of telomere length in D-gal-treated rats compared to the untreated control (P < .05). LF-DR9 lowered gene expression of p53, a known senescent biomarker, in gastrocnemius muscle and tibia compared to the control. The selected LAB strains also enhanced lipid, renal, and liver profile of rats, suggesting added potential of the strains in preventing aging-induced metabolic diseases. Strain LP-0291 and LH-1515 showed ability to adhere to mucin, no antibiotic resistance, tolerated and proliferated under gastric and intestinal simulated conditions, and inhibited the growth of pathogens Escherichia coli, Staphylococcus aureus, and Staphylococcus epidermidis, comparable to commercial probiotic LF-DR9 and Lactobacillus sakei Probio 65. This study provided an insight into the potential of LAB for exhibiting antisenescence effects, with potentials as new medicinal foods for targeted antiaging therapies.


Assuntos
Envelhecimento/fisiologia , Lactobacillus , Doenças Metabólicas/prevenção & controle , Probióticos/uso terapêutico , Encurtamento do Telômero , Proteínas Quinases Ativadas por AMP/metabolismo , Alcadienos/metabolismo , Animais , Células CACO-2 , Galactose , Humanos , Rim/metabolismo , Limosilactobacillus fermentum , Lactobacillus helveticus , Lacticaseibacillus paracasei , Metabolismo dos Lipídeos , Fígado/metabolismo , Masculino , Doenças Metabólicas/etiologia , Camundongos , Músculo Esquelético/metabolismo , Polímeros/metabolismo , Ratos Sprague-Dawley
5.
J Sports Sci ; 27(14): 1591-9, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19967588

RESUMO

The aims of this study were to establish the physical and physiological attributes of elite and sub-elite Malaysian male badminton players and to determine whether these attributes discriminate elite players from sub-elite players. Measurements and tests of basic anthropometry, explosive power, anaerobic recovery capacity, badminton-specific movement agility, maximum strength, and aerobic capacity were conducted on two occasions, separated by at least one day. The elite (n = 12) and sub-elite (n = 12) players' characteristics were, respectively: mean age 24.6 years (s = 3.7) and 20.5 years (s = 0.7); mass 73.2 kg (s = 7.6) and 62.7 kg (s = 4.2); stature 1.76 m (s = 0.07) and 1.71 m (s = 0.05); body fat 12.5% (s = 4.8) and 9.5% (s = 3.4); estimated VO(2max) 56.9 ml . kg(-1) . min(-1) (s = 3.7) and 59.5 ml . kg(-1) . min(-1) (s = 5.2). The elite players had greater maximum absolute strength in one-repetition maximum bench press (P = 0.015) compared with the sub-elite players. There were significant differences in instantaneous lower body power estimated from vertical jump height between the elite and sub-elite groups (P < 0.01). However, there was no significant difference between groups in shuttle run tests and on-court badminton-specific movement agility tests. Our results show that elite Malaysian male badminton players are taller, heavier, and stronger than their sub-elite counterparts. The test battery, however, did not allow us to discriminate between the elite and sub-elite players, suggesting that at the elite level tactical knowledge, technical skills, and psychological readiness could be of greater importance.


Assuntos
Atletas , Desempenho Atlético/fisiologia , Tamanho Corporal , Força Muscular/fisiologia , Aptidão Física/fisiologia , Esportes com Raquete/fisiologia , Adulto , Teste de Esforço , Humanos , Malásia , Masculino , Corrida , Levantamento de Peso , Adulto Jovem
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