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BACKGROUND: Aerobic exercise can decrease postprandial triglyceride (TG) concentrations but the relationship between exercise-induced energy deficits and postprandial lipemia is still unclear. The aim of the present study was to examine the effect of a single bout of aerobic exercise, with and without energy replacement, on postprandial lipemia and on peripheral blood mononuclear cell (PBMC) mRNA expression of very low density lipoprotein (VLDL) and low density lipoprotein (LDL) receptors and 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR). METHODS: Nine healthy male humans completed three two-day trials in a random order. On day 1, volunteers rested (CON), completed 60 minutes of treadmill walking at 50% of VO2peak (EX) or completed the same bout of walking but with the energy replaced afterwards with a glucose solution (EXG). On day 2, volunteers rested and consumed a high fat test meal in the morning. RESULTS: Total and incremental TG AUC were significantly lower on the EXG (P < 0.05) and EX (P < 0.05) trials than the CON trial with no difference between the two exercise trials. No significant difference was observed in VLDL or LDL receptor mRNA expression among the trials (P > 0.05). CONCLUSIONS: In conclusion, energy replacement by glucose did not affect the decrease in postprandial TG concentrations observed after moderate intensity exercise and exercise does not affect changes in PBMC HMGCR, VLDL and LDL receptor mRNA expression.
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Glucose/administração & dosagem , Triglicerídeos/sangue , Área Sob a Curva , HDL-Colesterol/sangue , Metabolismo Energético , Ácidos Graxos não Esterificados/sangue , Expressão Gênica , Humanos , Hidroximetilglutaril-CoA Redutases/genética , Hidroximetilglutaril-CoA Redutases/metabolismo , Leucócitos Mononucleares/metabolismo , Masculino , Esforço Físico , Período Pós-Prandial , Receptores de LDL/genética , Receptores de LDL/metabolismo , Caminhada , Adulto JovemRESUMO
In this study, we determined the cross-generation link between sedentary behavior of schoolchildren with their 6-year BMI progression pattern and metabolic disease category of their parents. Anthropometric data of 11,190 elementary schoolchildren (aged 13) were retrospectively tracked from 2003 to 2009, and classified into two groups: Normal (N = 9793) and Metabolic Disorders (N = 1397), based on the disease category of their parents (under at least one medication for stroke, coronary heart disease (CAD), diabetes, and hypertension). Schoolchildren's weekly time spending on reading, computer use, video game, music listening, radio listening, TV watching, and movie watching, was reported with parental assistance via questionnaires. Baseline BMI and 6 years BMI progression rate in Metabolic Disorders group were significantly higher than those in Normal group. In particular, offsprings from stroke parents exhibited the greatest baseline BMI across 6 years compared to the rest of the disease categories. For Metabolic Disorders group, time spending on computer use, video game, TV watching, and music listening of schoolchildren was significantly longer than Normal group. Reading, which occupied the largest portion of weekly sedentary time, was not contributed to the group difference on the BMI status of schoolchildren. The current study demonstrates that schoolchildren from family with at least one parent having metabolic disorders, particularly stroke, tend to be more sedentary and heavior than their age-matched normal peers. School-based obesity prevention programs are suggested for this specific group by restricting time spent on technology-associated sedentary behaviors and promoting sport activities.
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Comportamento do Adolescente , Atividade Motora , Obesidade/epidemiologia , Pais , Comportamento Sedentário , Adolescente , Adulto , Peso Corporal , Humanos , Relação entre Gerações , Atividades de Lazer , Obesidade/prevenção & controle , Fatores de Risco , Taiwan/epidemiologiaRESUMO
Badminton is recognized as the fastest racket sport in the world based on the speed of the birdie which can travel up to 426 km per hour. On the badminton court, players are not only required to track the moving badminton birdie (visual tracking and information integration) but also must anticipate the exact timing to hit it back (temporal estimation). However, the association of training experience related to visuomotor integration or temporal prediction ability remains unclear. In this study, we tested this hypothesis by examining the association between training experience and visuomotor performances after adjusting for age, education, and cardiovascular fitness levels. Twenty-eight professional badminton players were asked to perform a compensatory tracking task and a time/movement estimation task for measuring visuomotor integration and temporal prediction, respectively. Correlation analysis revealed a strong association between training experience and performance on visuomotor integration, indicating badminton training may be promoted to develop visuomotor integration ability. Furthermore, the regression model suggests training experience explains 32% of visuomotor integration performances. These behavioral findings suggest badminton training may facilitate the perceptual-cognitive performance related to visuomotor integration. Our findings highlight the potential training in visuomotor integration may apply to eye-hand coordination performance in badminton sport.
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Esportes com Raquete , Exercício Físico , Teste de Esforço , Movimento , Desempenho PsicomotorRESUMO
Cardiovascular health and aerobic capacity play crucial roles in determining the performance of athletes in the highly competitive sport of badminton. Few studies have directly compared heart rate variability (HRV), arterial stiffness, and aerobic capacity between male and female athletes, especially among badminton athletes. This study investigated sex differences in HRV, arterial stiffness, and aerobic capacity in badminton athletes. Elite badminton athletes were recruited and divided into male (n = 20, 21.0 ± 1.8 years old) and female (n = 16, 21.2 ± 2.3 years old) groups. Both groups performed an incremental treadmill running test for the evaluation of maximal oxygen consumption (V.O2max), anaerobic threshold, and time to exhaustion. They started exercising at a treadmill speed of 2.7 km/h and an inclination of 10% gradient for 3 min, and the speed and inclination were gradually increased every 3 min until they were exhausted or fatigued volitionally. HRV was examined using the Polar heart rate monitor over a period of 5 min at rest in the supine position. Subsequently, the index of arterial stiffness was examined under the same condition. Our results revealed significant differences between the male and female athletes in V.O2max (men: 60.38 ± 8.98 mL/kg/min, women: 48.13 ± 7.72 mL/kg/min, p < 0.05), anaerobic threshold (men: 41.50 ± 7.26 mL/kg/min, women: 32.51 ± 6.19 mL/kg/min, p < 0.05), time to exhaustion (men: 902.15 ± 120.15 s, women: 780.56 ± 67.63 s, p < 0.05), systolic blood pressure (men: 125.27 ± 7.76 mmHg, women: 107.16 ± 11.09 mmHg, p < 0.05), and arterial stiffness index (men: 63.56 ± 12.55, women: 53.83 ± 8.03, p < 0.05). However, no significant differences in HRV measures were observed between the two groups. These findings suggested that the male badminton athletes demonstrated significantly higher aerobic capacity than did the female athletes, but there were no significant differences in HRV measures. The female athletes exhibited superior arterial function, compared with their male counterparts.
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Esportes com Raquete , Rigidez Vascular , Adolescente , Adulto , Atletas , Teste de Esforço , Tolerância ao Exercício , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Consumo de Oxigênio/fisiologia , Esportes com Raquete/fisiologia , Adulto JovemRESUMO
A higher postprandial triglycerides response and hemorheological abnormalities may increase the incidence of metabolic disorders and negatively interfere with the aging process. A single session of preprandial endurance exercise was found to be effective in reducing triglyceride levels after a high-fat diet. However, whether the exercise-induced reduction in postprandial triglyceride levels influences hemorheological indicators remains unknown. This study aims to investigate the effects of postprandial lipemia on hemorheological properties and oxidative stress. Eight healthy young male participants completed two experimental trials. On day 1, the participants were randomly assigned to walk for 1 h at 50% VO2max (EE trial) or rest (CON trial). On day 2, participants rested and consumed a high-fat meal in the morning. Results: The postprandial area under the curve (AUC) of plasma TG concentration was significantly lower in EE compared to CON (EE: 9.2 ± 1.9; CON: 10.9 ± 1.7 mmol/L·h−1; p = 0.013; Cohen's d = 0.036). No significant difference was observed in hemorheological properties and MDA (p > 0.05). Endurance exercise effectively decreased postprandial TG concentration but did not influence the postprandial hemorheological properties and oxidative stress indicators.
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Improving the strength of grey cast iron wheel hubs will improve the safety of automobiles and have a great significance for energy saving and environmental protection. This paper systematically compares the calculation results of Python-based precipitation calculation and JmatPro software simulation with experiments. The results show that with a low mass fraction of niobium (0.098%) cuboid Niobium Carbide (NbC) precipitates do not form in the liquid phase; however, an elongated NbC niobium-rich phase may form during the solidification process and in the solid phase. However, cuboid NbC precipitates can be precipitated from the liquid phase when the niobium mass fraction is higher (0.27%, 0.46%). These results indicate that with the increasing niobium content the amount, particle size, and initial precipitation temperature of niobium carbide precipitated in the matrix structure will increase. According to the observation and statistical analysis of the microstructure, it is found that tensile strength will be improved with an increase in niobium content due to the refinement of the graphite and pearlite interlamellar spacing. In this paper, adding less than 0.32% of Nb to grey cast iron is recommended, considering the comprehensive cost and the effect of niobium in the material structure.
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In recent years, the popular adaptive front-lighting automobile headlight system has become a main emphasis of research that manufacturers will continue to focus great efforts on in the future. In this research we propose a new integral optical design for an automotive headlight system with an advanced light-emitting diode and digital micromirror device (DMD). Traditionally, automobile headlights have all been designed as a low beam light module, whereas the high beam light module still requires using accessory lamps. In anticipation of this new concept of integral optical design, we have researched and designed a single optical system with high and low beam capabilities. To switch on and off the beams, a DMD is typically used. Because DMDs have the capability of redirecting incident light into a specific angle, they also determine the shape of the high or low light beam in order to match the standard of headlight illumination. With collocation of the multicurvature reflection lens design, a DMD can control the light energy distribution and thereby reinforce the resolution of the light beam.
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Óptica e Fotônica , Meios de Transporte , Desenho de Equipamento/instrumentação , Humanos , Luz , Iluminação/instrumentação , Software , Visão OcularRESUMO
Exercise is recommended as a lifestyle intervention in preventing hypertension based on epidemiological findings. However, previous intervention studies have presented mixed results. This discrepancy could be associated with shortcomings related to sample sizes or the inclusion of normotensive participants. The aim of this prospective cohort study (N = 463) was to compare the chronic effect of increasing sports training time on resting blood pressure for normotensives and hypertensives. We assessed systolic blood pressure, diastolic blood pressure, body mass index (BMI), and homeostasis model assessment for insulin resistance (HOMA-IR) for 69 untreated hypertensive patients (age 20.6 +/- 0.1 years, systolic blood pressure >140 mmHg) and 394 normotensive controls (age 20.6 +/- 0.1 years) before training and at follow-up visits at 12 months. All participants enrolled in various sports training lessons for 8 hours a week. The baseline BMI and HOMA-IR in the hypertensive group were significantly higher than those in the control group. For the normotensive control group, no significant changes in systolic and diastolic blood pressure were observed after training. However, for the hypertensives, systolic and diastolic blood pressure were significantly reduced after training by approximately 15 mmHg and approximately 4 mmHg, respectively, and HOMA-IR was reduced by approximately 25%. In conclusion, the effect of sports training to lower blood pressure was confined to the group of hypertensives, which may account for the overall minimal reduction in blood pressure observed in previous intervention studies.
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Pressão Sanguínea/fisiologia , Exercício Físico/fisiologia , Hipertensão/terapia , Resistência à Insulina/fisiologia , Educação Física e Treinamento , Esportes/fisiologia , Adulto , Análise de Variância , Glicemia/análise , Índice de Massa Corporal , Terapia por Exercício , Feminino , Humanos , Hipertensão/fisiopatologia , Insulina/sangue , Masculino , Estudos Prospectivos , Valores de Referência , Adulto JovemRESUMO
UNLABELLED: Swimming is a lifestyle intervention recommended by many clinicians in the prevention and treatment of hypertension. Yet, not all studies have agreed that swimming training can reduce blood pressure (BP). Inclusion of normotensive subjects could be a confounder for discrepancies among studies. In this one-year longitudinal study, long-term effects of swimming training on BP were investigated in 7 mild hypertensive patients (systolic BP (SBP) > 140 mmHg) and 16 normotensive controls. At baseline, these subjects (aged 21.5 +/- 0.1 years) did not participate in any form of sport training activity for the previous 3 months before enrollment into the training program. The training distance progressed from 0 (baseline) to 7 kilometers per week. BP and the homeostasis model assessment for insulin resistance (HOMA-IR) were determined under fasted condition at baseline and 48 h after the last swimming bout. The hypertensive patients displayed significantly greater HOMA-IR than age-matched normotensive controls. When data of all subjects were pooled, plasma glucose concentration was only slightly lowered after training, but weight, height, body mass index, SBP, diastolic BP (DBP) and HOMA-IR values were not significantly altered. However, when observation was restricted to the hypertensive patients, swimming training significantly lowered SBP by approximately 17 mmHg, concurrent with 41% reduction in HOMA-IR. Intriguingly, SBP in the normotensive subjects was elevated by approximately 6 mmHg after training. CONCLUSIONS: The present study found normalization rather than universal reduction effect of swimming training on BP. Furthermore, the BP-lowering effect of training in hypertensive patients appears to be associated with improvement in insulin sensitivity.
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Pressão Sanguínea/fisiologia , Hipertensão/fisiopatologia , Resistência à Insulina/fisiologia , Natação/fisiologia , Glicemia/metabolismo , Exercício Físico/fisiologia , Terapia por Exercício , Humanos , Hipertensão/terapia , Estudos Longitudinais , Resultado do Tratamento , Adulto JovemRESUMO
Previous studies on athletes' cognitive functions have reported superior performance on tasks measuring attention and sensorimotor abilities. However, how types of sports training shapes cognitive profile remains to be further explored. In this study, we recruited elite athletes specialized in badminton (N = 35, female = 12) and volleyball (N = 29, female = 13), as well as healthy adult controls (N = 27, female = 17) who had not receive any regular sports training. All participants completed cognitive assessments on spatial attention, sensory memory, cognitive flexibility, motor inhibition, and the attention networks. The results showed that athletes generally showed superior performance on selective cognitive domains compared to healthy controls. Specifically, compared to the healthy control, volleyball players showed superior on iconic memory, inhibitory control of action, and attentional alerting, whereas badminton players showed advantages on iconic memory and basic processing speed. Overall, volleyball players outperformed badminton players on those tasks require stimulus-driven visual attention and motor inhibition, likely due to different training modalities and characteristics of specialty that involves even more complex cognitive processes. To conclude, our findings suggest cognitive plasticity may drive by sports training in team/individual sports expertise, manifesting cognitive profile in sport expertise with distinct training modalities.
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Atletas , Atenção , Cognição , Inibição Psicológica , Destreza Motora , Plasticidade Neuronal , Adulto , Feminino , Humanos , Masculino , Memória , Testes Neuropsicológicos , Esportes com Raquete , Inquéritos e Questionários , Visão Ocular , Voleibol , Adulto JovemRESUMO
INTRODUCTION: A recent US Major League Baseball (MLB) rule change requires baseball pitchers to deliver pitches within 12 s. PURPOSES: To examine the effect of three between-pitch rest intervals on throwing performance during a simulated seven-inning game and muscle damage during postgame recovery. DESIGN: A randomized counterbalanced study. METHODS: Seven intercollegiate pitchers threw 15 pitches per inning for seven innings with rest interval trials of 8, 12, and 20 s between pitches and 5 min between innings. Pitchers threw aimed fastballs at their best effort. Trials were separated by ≥2 wk. RESULTS: Progressive decreases in pitching speed and accuracy below baseline (first inning of 20-s trial) occurred after fourth inning during the 8-s and 12-s trials, but not the 20-s trial. Plasma creatine kinase elevated 48 h later for the 8-s and 12-s trials (+105% and +75%, P < 0.01), but not the 20-s trial (+26%, no significance). A transient interleukin (IL)-6 surges immediately after the game for the 8- and 12-s trials (+265%, +128%, P < 0.01) above baseline. IL-6 reversed below the level of 20-s trial at 48 h after game, whereas IL-10 increased significantly above the level of 20-s trial. CONCLUSIONS: Under the same pitching load, decreasing rest interval from 20 to 12 s or less results in an early-onset performance loss during a game and increases in muscle damage and inflammation for more than 2 d after a game. Our data do not favor the current rule change in concern of keeping musculoskeletal health of pitchers.
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Desempenho Atlético/fisiologia , Beisebol/lesões , Beisebol/fisiologia , Músculo Esquelético/lesões , Músculo Esquelético/fisiopatologia , Creatina Quinase/sangue , Humanos , Interleucina-10/sangue , Interleucina-6/sangue , Masculino , Fadiga Muscular/fisiologia , Mialgia/etiologia , Miosite/sangue , Miosite/etiologia , Fatores de Tempo , Adulto JovemRESUMO
Phthalate ester (PAE) accumulation in crops poses great risks to human health and has aroused great concern. Here, we investigated variations in di-n-butylphthalate (DBP) and di-(2-ethylhexyl) phthalate (DEHP) accumulation by various Chinese flowering cabbage cultivars and revealed their variation mechanism. There were significant differences (p < 0.05) in shoot PAE concentrations of 28 cultivars. Moreover, significant positive correlations between DBP and DEHP concentrations in shoots of all cultivars indicated that they could be taken up simultaneously by various cultivars. Due to the lower translocation factor of low-PAE accumulator, its shoot PAEs concentrations were much lower than root compared to high-PAE accumulator. Further, subcellular distribution showed that PAE concentrations of root cell walls and organelles were much higher than those of shoots in low-PAE accumulator. Therefore, lower translocation from root to shoot and more PAEs accumulating in cell walls and organelles of root might act as main formation mechanism of low-PAE accumulator.
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Brassica/metabolismo , Dibutilftalato/metabolismo , Ácidos Ftálicos/metabolismo , Poluentes do Solo/metabolismo , Produtos Agrícolas/metabolismo , Dibutilftalato/análise , Ésteres , Humanos , Ácidos Ftálicos/análise , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Solo/química , Poluentes do Solo/análiseRESUMO
OBJECTIVE: To evaluate the therapeutic effect of Parkinson's disease combined with overactive bladder syndrome (GAB) treated with combined therapy of oral administration of Tolterodine with low dose and electroacuponcture. METHODS: Sixty cases of Parkinson's disease combined with GAB were randomly divided into a combined acupuncture and medication group (group A) and a medication group (group B), 30 cases in each group. In both groups, Madopar basic doses were same, and anticholinergic agents such as Artane were stopped. In group A, Tolterodine was orally taken for 1 mg, twice a day; Baihui (GV 20), Sishengcong (EX-HN 1) and Yintang (EX-HN 3) were punctured with electroacupuncture, once a day. In group B, Tolterodine was orally taken for 2 mg, twice a day. After 6 weeks, the changes of urination and UPDRS III scores were observed, and the adverse reactions were recorded in both groups. RESULTS: After treatment, the frequency of average urination of 24 hours, frequency of incontinence of 24 hours and average urine volume at a time were obviously improved (all P < 0. 01), of which, the above items in group A were superior to those in group B (all P < 0. 05) the UPDRSIII score in group A was superior to that in group B (P < 0.05). The adverse reactions in group A were less than those in group B. CONCLUSION: The therapeutic effect of Parkinson' s disease combined with GAB treated with combined therapy of Tolterodine with low dose and electroacupuncture is superior to that of complete dose of Tolterodine with oral administration, with less adverse reactions. And it also can improve the motor symptom of Parkinson's disease patients.
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Compostos Benzidrílicos/uso terapêutico , Cresóis/uso terapêutico , Eletroacupuntura , Doença de Parkinson/terapia , Fenilpropanolamina/uso terapêutico , Bexiga Urinária Hiperativa/terapia , Adulto , Idoso , Terapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/tratamento farmacológico , Tartarato de Tolterodina , Bexiga Urinária Hiperativa/tratamento farmacológicoRESUMO
The difference in leaf stable carbon isotope discrimination (delta) of 18 representative Schima superba provenances was investigated based on three provenance trails located at Jian' ou of Fujian Province and Chun' an and Qingyuan of Zhejiang Province, and the geographic variation pattern and the effects of trial site and provenances growth rate were studied. Significant differences in leaf delta were observed among the provenaces, and the differences in leaf delta value between the highest and lowest provenances reached 6.9%, 3.0%, and 3.7% in 3 experimental sites, respectively. A classic latitudinal clinical variation pattern was found, because there were significant correlations between the leaf delta value and the latitude of seed sources in all the 3 sites while no significant correlations were observed between the leaf delta value and the longitude of the seed sources. The southern provenances showed higher leaf delta value than the northern provenances, indicating that the water use efficiency (WUE) was lower in southern provenances. The leaf delta value of different provenances was demonstrated to be greatly affected by the environment of trial sites. The leaf delta value increased significantly with the improvement of site environment and with the increase of annual rainfall. Significant positive correlations were observed between the leaf delta value and the growth traits including tree height, DBH, total number of lateral branches, and length of the strongest lateral branch, which indicated that the provenances with higher growth rate and denser crown had larger leaf delta value. Two and four superior provenances with high growth rate and low leaf delta value (or high WUE) were selected for Jian' ou of Fujian and Chun' an of Zhejiang, respectively.
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Isótopos de Carbono/metabolismo , Variação Genética , Theaceae/genética , Theaceae/metabolismo , Folhas de Planta/metabolismo , Locos de Características Quantitativas , Theaceae/classificação , Água/metabolismoRESUMO
OBJECTIVE: Weight status and abnormal liver function are the two factors that influence whole-body insulin sensitivity. The main goal of the study was to compare insulin sensitivity in athletes (n=757) and physically active controls (n=670) in relation to the two factors. METHODS: Homeostatic metabolic assessment for insulin resistance (HOMA-IR), weight status, and abnormal liver function (alanine aminotransferase and aspartate aminotransferase) were determined from 33 sports disciplines under morning fasted condition. This study was initiated in autumn 2006 and repeated in autumn 2007 (n=1508) to ensure consistency of all observations. RESULTS: In general, HOMA-IR and blood pressure levels in athletes were significantly greater than those in physically active controls but varied widely with sport disciplines. Rowing and short-distance track athletes had significantly lower HOMA-IR values and archery and field-throwing athletes had significantly higher values than the control group. Intriguingly, athletes from 22 sports disciplines displayed significantly greater body mass index values above control values. Multiple regression analysis showed that, for non-athlete controls, body mass index was the only factor that contributed to the variations in HOMA-IR. For athletes, body mass index and alanine aminotransferase independently contributed to the variation of HOMA-IR. CONCLUSION: This is the first report documenting HOMA-IR values in athletes from a broad range of sport disciplines. Weight status and abnormal liver function levels appear to be the major contributors predicting insulin sensitivity for the physically active population.