RESUMEN
Working memory (WM) plays an important role in daily life and is known to correlated with aerobic fitness. However, whether the relationship between aerobic fitness and WM is dependent on the stimulus modality or is associated with one or multiple subprocesses involved in WM remains unknown. Accordingly, this study utilized event-related potentials (ERPs) to comprehensively examine the encoding, preparation, and retrieval processes during verbal and spatial WM performance. Eighty-eight young adults aged 18-30years were recruited to participate in two laboratory visits on separate days. On day 1, aerobic fitness was assessed by maximum oxygen consumption (VËO2max) during a treadmill-based graded exercise test. On day 2, participants completed verbal and spatial WM tasks while P2, contingent negative voltage (CNV), and P3 components of ERP were recorded during the encoding, preparatory, and retrieval stages of WM, respectively. Results of hierarchical regression analysis showed that VËO2max was positively correlated with response accuracy during the high-demanding condition of spatial WM after controlling for age, sex, and self-reported physical activity. Additionally, a higher level of VËO2max was associated with larger terminal CNV amplitude at the Cz electrode during the high-demanding condition of spatial WM. These findings suggest that aerobic fitness may have selective beneficial associations with the motor preparatory process and subsequent task performance requiring a greater amount of spatial information but not the encoding and retrieval stages nor the verbal modality of WM.
Asunto(s)
Electroencefalografía , Potenciales Evocados , Memoria a Corto Plazo , Memoria Espacial , Humanos , Masculino , Femenino , Adulto Joven , Memoria a Corto Plazo/fisiología , Adulto , Potenciales Evocados/fisiología , Adolescente , Memoria Espacial/fisiología , Consumo de Oxígeno/fisiología , Ejercicio Físico/fisiología , Aptitud Física/fisiología , Prueba de EsfuerzoRESUMEN
OBJECTIVES: Determine the effect of incorporating mindfulness-based activities into the recovery intervals of high-intensity interval training (HIIT) on mindfulness induction and subsequent executive function performance. DESIGNS: A within-subject crossover trial. METHODS: Forty adults participated in two experimental conditions, including a 30-min bout of HIIT involving mindfulness recovery intervals (Mindful) and a 30-min bout of HIIT without mindfulness recovery intervals (Non-mindful), on two separate days in counterbalanced order. Before and after each condition, participants completed the flanker task, switch-flanker task, and n-back task to measure inhibitory control, cognitive flexibility, and working memory, respectively. RESULTS: A higher level of mindfulness state was observed following the Mindful condition than the Non-mindful condition. Dispositional mindfulness was positively correlated with the level of the mindful state only during the Mindful condition but not the Non-mindful condition. The switch-flanker response accuracy was improved from the pretest to posttest during the Non-mindful condition but remained unchanged over time during the Mindful condition. Time-related improvements in the flanker and n-back task outcomes were observed for both the Mindful and Non-mindful conditions and did not differ between conditions. CONCLUSION: Although incorporating mindfulness-based activities during the recovery intervals of HIIT successfully led to greater state-related mindfulness, such a heightened mindful state did not correspond with additional modulation in inhibitory control and working memory performance while attenuating HIIT-related positive changes in task performance requiring cognitive flexibility.
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Entrenamiento de Intervalos de Alta Intensidad , Atención Plena , Adulto , Humanos , Cognición , Función Ejecutiva , Memoria a Corto Plazo , Estudios CruzadosRESUMEN
OBJECTIVES: Determine the acute effect of high-intensity interval training as an alternative of moderate-intensity aerobic exercise on behavioral and neuroelectric measures of inhibitory control in preadolescent children. DESIGN: A randomized controlled trial. METHODS: Seventy-seven children (8-10â¯years) were randomly assigned to three groups to complete a modified flanker task to measure behavioral and neuroelectric (N2/P3 of event-related potential and frontal theta oscillations) outcomes of inhibitory control before and after a 20-min session of high-intensity interval training (Nâ¯=â¯27), moderate-intensity aerobic exercise (Nâ¯=â¯25), and sedentary reading activity (Nâ¯=â¯25). RESULTS: The accuracy of the inhibitory control performance improved over time across three groups but response time was selectively improved only for the high-intensity interval training group. Analysis on N2 showed a time-related decrease in N2 latency selectively for the high-intensity interval training but not the other groups. Analysis on P3 showed a time-related decrease in P3 amplitude for the sedentary and high-intensity interval training groups while the moderate-intensity aerobic exercise group exhibited maintained P3 amplitude from the pretest to the posttest and a larger P3 amplitude compared with the high-intensity interval training group at the posttest. While there was evidence of conflict-induced modulation of frontal theta oscillations, such an effect was unaffected by exercise interventions. CONCLUSIONS: A single bout of high-intensity interval training has facilitating effects on the processing speed involving inhibitory control in preadolescent children but not neuroelectric index of attention allocation that only benefited from moderate-intensity aerobic exercise.
Asunto(s)
Encéfalo , Entrenamiento de Intervalos de Alta Intensidad , Humanos , Niño , Encéfalo/fisiología , Ejercicio Físico/fisiología , Potenciales Evocados/fisiología , Tiempo de Reacción/fisiología , Atención/fisiologíaRESUMEN
Background: Firefighters are required to have high levels of aerobic and anaerobic power because they often perform physically demanding work in dangerous environments. Therefore, it is important to find out salient factors influencing voluntary exercise training among Korean firefighters based on well-validated theory. Methods: The present study conducted an elicitation study to elicit salient behavioral, normative, and control beliefs about exercise training among Korean firefighters and identified salient beliefs that have a significant indirect effect on behavior through intention using structural equation modeling. Results: Although ten modal salient beliefs obtained from our elicitation study are similar to those elicited from previous TPB belief-based research with a focus on exercise behavior, only three of these (i.e., "improves my physical ability" (coef. = 0.078, p = 0.006), "takes too much time" (coef. = 0.064, p = 0.023), and "colleagues" (coef. = 0.069, p = 0.016) indirectly influenced exercise training behavior through intention among Korean firefighters. Conclusions: Our results may contribute to the literature by providing important information suggesting that three modal salient beliefs are major cognitive determinants of exercise training behavior among Korean firefighters and they may play an essential role in developing effective programs or policies for promoting Korean firefighters' exercise training.
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Conducta , Ejercicio Físico/psicología , Bomberos/psicología , Bomberos/estadística & datos numéricos , Adulto , Femenino , Humanos , Intención , Masculino , Persona de Mediana Edad , República de CoreaRESUMEN
BACKGROUND: According to the National Fire Agency, 69% of South Korean firefighters prefer the three circuit system. Since the three circuit system involves working for 24 h consecutively, it could reduce work performance of firefighters and their participation in exercise training (ET) and fitness levels could be affected by shift type. The present study examined the impact of shift type on ET and identified the interaction effect between shift type and city size on ET among South Korean firefighters. METHODS: A series of logistic regression models were used to analyze the data collected from incumbent outside workers among Korean firefighters (N = 5196) in 2017. RESULTS: Firefighters under the 3 circuit system participated in ET less frequently than did those under the 21 circuit system, and the difference was greater in large cities than in small towns. This could be because of the greater opportunity to participate in leisure activities in large cities, or because participating in ET is easier for firefighters in small towns, who tend to be less busy than those in large cities. CONCLUSIONS: The three circuit system is not feasible in the present situation in South Korea. Therefore, an environment suitable for the three circuit system should be established.
Asunto(s)
Ejercicio Físico , Bomberos , Horario de Trabajo por Turnos , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Aptitud Física , República de CoreaRESUMEN
BACKGROUND: This systematic review was performed to investigate the effects of Chinese herbal nedicine (CHM) on cognitive function and activity of daily living (ADL) in individuals with Alzheimer's disease. METHODS: Five electronic databases (Medline, Embase, Cinahl, PsycArticles, and CNKI) were searched from inception to January 2019. Randomized controlled trials (RCTs) assessing the effect of CHM on cognition and activity of daily living in adults with Alzheimer's disease were included. We pooled the effects size using the Comprehensive Meta-Analysis Software. Cochrane risk of bias tool was used to evaluate the study quality. RESULTS: Twenty-five RCTs (1855 individuals with AD) were included in this review. Overall findings of this meta-analysis indicated that CHM improved the cognitive function (SMD = 0.66, 95% CI [0.44, 0.89], I 2 = 77.9%, p < 0.001) and ADL (SMD = 0.38, 95% CI [0.25, 0.49], I 2 = 35.3%, p < 0.001) compared with conventional drugs. No publication biases were observed on both cognitive function and ADL. CONCLUSION: CHM may have potential effects for improving cognitive function and ADL for individuals with AD compared with conventional drug therapies. However, the evidence is limited because of high risk of bias of the included trials.
RESUMEN
Escherichia coli O157:H7 is recognized as a significant food-borne pathogen, so rapid identification is important for food hygiene management and prompt epidemiological investigations. The limited prevalence data on Shiga toxin-producing E. coli (STEC) and E. coli O157:H7 in foods and animals in Korea made an assessment of the risks difficult, and the options for management and control unclear. The prevalence of the organisms was examined by newly developed kit-E. coli O157:H7 Rapid kit. For the isolation of E. coli O157:H7, conventional culture, immunomagnetic separation, and E. coli O157:H7 Rapid kit were applied, and multiplex PCR and randomly amplified polymorphic DNA (RAPD) were performed for the molecular determination. There was high molecular relatedness among 11 Korean isolates and 17 U.S. strains at 63% level. Additionally, distinct differentiation between pig and cattle isolates was determined. It implied that RAPD had a capacity to distinguish strains with different sources, however it could not discriminate among isolates according to their differences in the degree of virulence. In antimicrobial susceptibility tests, 45.5% of isolates showed antibiotic resistance to two or more antibiotics. Unlike the isolates from other countries, domestic isolates of E. coli O157:H7 was mainly resistant to ampicillin and tetracyclines. In summary, the application of E. coli O157:H7 Rapid kit may be useful to detect E. coli O157:H7 due to its sensitivity and convenience. Moreover, combinational analysis of multiplex PCR together with RAPD can aid to survey the characteristics of isolates.