Objective:This study aimed to examine(1)the independent effects of hypoxia on cognitive function and(2)the effects of exercise on cognition while under hypoxia.Methods:Design:Systematic review with meta-analysis.Data ...Objective:This study aimed to examine(1)the independent effects of hypoxia on cognitive function and(2)the effects of exercise on cognition while under hypoxia.Methods:Design:Systematic review with meta-analysis.Data sources:PubMed,Scopus,Web of Science,PsychInfo,and SPORTDiscus were searched.Eligibility criteria for selecting studies:randomized controlled trials and nonrandomized controlled studies that investigated the effects of chronic or acute exercise on cognition under hypoxia were considered(Aim 2),as were studies investigating the effects of hypoxia on cognition(Aim 1).Results:In total,18 studies met our inclusionary criteria for the systematic review,and 12 studies were meta-analyzed.Exposure to hypoxia impaired attentional ability(standardized mean difference(SMD)=-0.4),executive function(SMD=-0.18),and memory function(SMD=-0.26),but not information processing(SMD=0.27).Aggregated results indicated that performing exercise under a hypoxia setting had a significant effect on cognitive improvement(SMD=0.3,95%confidence interval:0.14-0.45,I^2=54%,p<0.001).Various characteristics(e.g.,age,cognitive task type,exercise type,exercise intensity,training type,and hypoxia level)moderated the effects of hypoxia and exercise on cognitive function.Conclusion:Exercise during exposure to hypoxia improves cognitive function.This association appears to be moderated by individual and exercise/hypoxia-related characteristics.展开更多
Purpose：This study aimed（1） to examine the longitudinal trajectories in objectively measured physical activity（PA）;（2） to identify unknown（i.e.,latent） subgroups with distinct trajectories;and（3） to examine...Purpose：This study aimed（1） to examine the longitudinal trajectories in objectively measured physical activity（PA）;（2） to identify unknown（i.e.,latent） subgroups with distinct trajectories;and（3） to examine the correlates of latent subgroups among community dwelling women.Methods：The study sample included a total of 669 women from the Women＇s Injury Study,a 5-year prospective cohort study conducted from2007 in the Southwest Central region of the US.Pedometer-based step-count data across 18 consecutive months were fitte to a latent growth model（LGM） and a latent class growth model（LCGM）.Baseline characteristics were regressed on latent class membership.Results：The longitudinal change in PA was best fi to a piecewise LGM with seasonal transitions.Significant y increased and decreased levels of PA were observed during the spring,fall,and winter,respectively（p〈0.001）.Three latent subgroups with distinct PA trajectories were identifie（low-active（46.8%）,somewhat-active（41.3%）,and active（11.9%））.Age and body fat percentage at the baseline significant y explained the likelihoods of being in low-active subgroup.Conclusion：Seasonal variations in PA among women were observed but may not be practically significant A relatively large portion of the sample showed low levels of PA for long periods.Intervention strategies should be considered for women who are overweight or obese,and aged 〉40 years old to promote PA during the life course.展开更多
Hepatic gluconeogenesis is the central pathway for glucose generation in the body.The imbalance between glucose synthesis and uptake leads to metabolic diseases such as obesity,diabetes,and cardiovascular diseases.Sma...Hepatic gluconeogenesis is the central pathway for glucose generation in the body.The imbalance between glucose synthesis and uptake leads to metabolic diseases such as obesity,diabetes,and cardiovascular diseases.Small leucine zipper protein(sLZIP)is an isoform of LZIP and it mainly functions as a transcription factor.Although sLZIP is known to regulate the transcription of genes involved in various cellular processes,the role of sLZIP in hepatic glucose metabolism is not known.In this study,we investigated the regulatory role of sLZIP in hepatic gluconeogenesis and its involvement in metabolic disorder.We found that sLZIP expression was elevated during glucose starvation,leading to the promotion of phosphoenolpyruvate carboxylase and glucose-6-phosphatase expression in hepatocytes.However,sLZIP knockdown suppressed the expression of the gluconeogenic enzymes under low glucose conditions.sLZIP also enhanced glucose production in the human liver cells and mouse primary hepatic cells.Fasting-induced cyclic adenosine monophosphate impeded sLZIP degradation.Results of glucose and pyruvate tolerance tests showed that sLZIP transgenic mice exhibited abnormal blood glucose metabolism.These findings suggest that sLZIP is a novel regulator of gluconeogenic enzyme expression and plays a role in blood glucose homeostasis during starvation.展开更多
This experiment was designed to accommodate the diversified verbal,mathematical,and spatial skills of young adults,which have not yet to be collectively evaluated in research projects focused on acute exercise and cre...This experiment was designed to accommodate the diversified verbal,mathematical,and spatial skills of young adults,which have not yet to be collectively evaluated in research projects focused on acute exercise and creativity among college students.While emerging research suggests that acute moderate-intensity exercise may influence human creativity,creativity during and after exercise has not been experimentally investigated.Such differences are plausible,as previous work demonstrates that memory can be differentially influenced based on whether the memory task occurs during or after exercise.Therefore,the purpose of this study was to examine the effects of acute moderate‐intensity treadmill walking,for 15 min,on verbal,mathematical,and spatial insight creativity performance while considering the timing of the exercise and creativity tasks.Among a sample of 20 undergraduate students,all completed three randomized laboratory visits in this within-subjects design:control condition,insight problem-solving following exercise,and insight problem-solving during exercise.They also completed six insight creativity tasks(two verbal,two mathematical,and two spatial tasks)per visit,with the order of task-presentation randomized and counterbalanced across the three visits.Average insight creativity scores were similar across the three exercise manipulations:That is,verbal insight[F(2,18)=0.689,P=0.51],mathematical insight[F(2,18)=0.033,P=0.97],and spatial insight[F(2,18)=1.0,P=0.38]performance were not statistically significant across the three visits.Thus,moderate-intensity acute exercise may not appreciably influence verbal,mathematical or spatial insight creativity.展开更多
The purpose of this meta-analysis was to evaluate the effects of acute exercise on short-term memory improvement.The computerized literature searches using electronic databases and examinations of reference lists from...The purpose of this meta-analysis was to evaluate the effects of acute exercise on short-term memory improvement.The computerized literature searches using electronic databases and examinations of reference lists from relevant studies yielded six studies meeting our inclusionary criteria.In a total of six studies,16 standardized regression coefficient effect sizes(ESs)were calculated to be meta-analyzed.The meta-analyses showed a statistically significant increase in short-term memory improvement across both the exercise and non-exercise control groups in trials 1-5[ES=0.96,95%CI(0.95,0.97),P<0.001].However,there was no significant subgroup difference between exercise and control groups(Q_(b)=0.40,df=1,P=0.53).Our meta-analytic review provides suggestive evidence that an acute bout of exercise prior to learning does not result in short-term memory improvement to a greater extent than a non-exercise control.Additional research is needed to further evaluate whether acute exercise enhances long-term memory via enhanced learning and/or post-learning mechanisms.展开更多
Purpose The maximal isometric strength test is widely used in general,athletic,and clinical populations.However,this test has often been used without considering how many trials are needed or appropriate to obtain rel...Purpose The maximal isometric strength test is widely used in general,athletic,and clinical populations.However,this test has often been used without considering how many trials are needed or appropriate to obtain reliable test scores.Thus,the aim of this study was to examine the maximal isometric strength test in upper and lower body for the purpose of determining the reliability of best isometric strength score and the ideal number of trials for a reliable test score.Methods One hundred and twelve healthy adults were assigned to four different groups(elbow flexion with the vertical and horizontal forearm positions,knee flexion,and knee extension).After familiarization,all participants performed three maxi-mal isometric voluntary contractions with the designated muscle group.The reliability of best isometric strength test score was calculated using the intraclass correlation coefficients(ICC)from a one-way ANOVA model.The Spearman-Brown prophecy formula was used to identify the minimum number of trials needed.Results The reliability of the best maximal isometric strength test scores out of three trials were high(ICC=0.92 to 0.98).At least two trials of maximal isometric strength test for knee flexion and one trial for elbow flexion and knee extension would be necessary to achieve an acceptable reliability coefficient of 0.80.In addition,one trial of elbow flexion would be enough for women,but men would need two trials.Conclusions Our results suggest that overall,at least two trials would be necessary to test isometric strength in upper and lower body muscles in both sexes.展开更多
基金supported by grants from the National Natural Science Foundation of China(Grant#31671150)Guangdong Province Key Project(Grant#2018B030335001).
文摘Objective:This study aimed to examine(1)the independent effects of hypoxia on cognitive function and(2)the effects of exercise on cognition while under hypoxia.Methods:Design:Systematic review with meta-analysis.Data sources:PubMed,Scopus,Web of Science,PsychInfo,and SPORTDiscus were searched.Eligibility criteria for selecting studies:randomized controlled trials and nonrandomized controlled studies that investigated the effects of chronic or acute exercise on cognition under hypoxia were considered(Aim 2),as were studies investigating the effects of hypoxia on cognition(Aim 1).Results:In total,18 studies met our inclusionary criteria for the systematic review,and 12 studies were meta-analyzed.Exposure to hypoxia impaired attentional ability(standardized mean difference(SMD)=-0.4),executive function(SMD=-0.18),and memory function(SMD=-0.26),but not information processing(SMD=0.27).Aggregated results indicated that performing exercise under a hypoxia setting had a significant effect on cognitive improvement(SMD=0.3,95%confidence interval:0.14-0.45,I^2=54%,p<0.001).Various characteristics(e.g.,age,cognitive task type,exercise type,exercise intensity,training type,and hypoxia level)moderated the effects of hypoxia and exercise on cognitive function.Conclusion:Exercise during exposure to hypoxia improves cognitive function.This association appears to be moderated by individual and exercise/hypoxia-related characteristics.
基金supported by the grant from the National Institutes of Health–National Institute of Arthritis and Musculoskeletal and Skin Diseases(No.R01 AR052459)
文摘Purpose：This study aimed（1） to examine the longitudinal trajectories in objectively measured physical activity（PA）;（2） to identify unknown（i.e.,latent） subgroups with distinct trajectories;and（3） to examine the correlates of latent subgroups among community dwelling women.Methods：The study sample included a total of 669 women from the Women＇s Injury Study,a 5-year prospective cohort study conducted from2007 in the Southwest Central region of the US.Pedometer-based step-count data across 18 consecutive months were fitte to a latent growth model（LGM） and a latent class growth model（LCGM）.Baseline characteristics were regressed on latent class membership.Results：The longitudinal change in PA was best fi to a piecewise LGM with seasonal transitions.Significant y increased and decreased levels of PA were observed during the spring,fall,and winter,respectively（p〈0.001）.Three latent subgroups with distinct PA trajectories were identifie（low-active（46.8%）,somewhat-active（41.3%）,and active（11.9%））.Age and body fat percentage at the baseline significant y explained the likelihoods of being in low-active subgroup.Conclusion：Seasonal variations in PA among women were observed but may not be practically significant A relatively large portion of the sample showed low levels of PA for long periods.Intervention strategies should be considered for women who are overweight or obese,and aged 〉40 years old to promote PA during the life course.
基金This research was supported by Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Science,ICT and Future Planning(NRF-2017R1E1A1A01073955)and the Korea University Grant.
文摘Hepatic gluconeogenesis is the central pathway for glucose generation in the body.The imbalance between glucose synthesis and uptake leads to metabolic diseases such as obesity,diabetes,and cardiovascular diseases.Small leucine zipper protein(sLZIP)is an isoform of LZIP and it mainly functions as a transcription factor.Although sLZIP is known to regulate the transcription of genes involved in various cellular processes,the role of sLZIP in hepatic glucose metabolism is not known.In this study,we investigated the regulatory role of sLZIP in hepatic gluconeogenesis and its involvement in metabolic disorder.We found that sLZIP expression was elevated during glucose starvation,leading to the promotion of phosphoenolpyruvate carboxylase and glucose-6-phosphatase expression in hepatocytes.However,sLZIP knockdown suppressed the expression of the gluconeogenic enzymes under low glucose conditions.sLZIP also enhanced glucose production in the human liver cells and mouse primary hepatic cells.Fasting-induced cyclic adenosine monophosphate impeded sLZIP degradation.Results of glucose and pyruvate tolerance tests showed that sLZIP transgenic mice exhibited abnormal blood glucose metabolism.These findings suggest that sLZIP is a novel regulator of gluconeogenic enzyme expression and plays a role in blood glucose homeostasis during starvation.
文摘This experiment was designed to accommodate the diversified verbal,mathematical,and spatial skills of young adults,which have not yet to be collectively evaluated in research projects focused on acute exercise and creativity among college students.While emerging research suggests that acute moderate-intensity exercise may influence human creativity,creativity during and after exercise has not been experimentally investigated.Such differences are plausible,as previous work demonstrates that memory can be differentially influenced based on whether the memory task occurs during or after exercise.Therefore,the purpose of this study was to examine the effects of acute moderate‐intensity treadmill walking,for 15 min,on verbal,mathematical,and spatial insight creativity performance while considering the timing of the exercise and creativity tasks.Among a sample of 20 undergraduate students,all completed three randomized laboratory visits in this within-subjects design:control condition,insight problem-solving following exercise,and insight problem-solving during exercise.They also completed six insight creativity tasks(two verbal,two mathematical,and two spatial tasks)per visit,with the order of task-presentation randomized and counterbalanced across the three visits.Average insight creativity scores were similar across the three exercise manipulations:That is,verbal insight[F(2,18)=0.689,P=0.51],mathematical insight[F(2,18)=0.033,P=0.97],and spatial insight[F(2,18)=1.0,P=0.38]performance were not statistically significant across the three visits.Thus,moderate-intensity acute exercise may not appreciably influence verbal,mathematical or spatial insight creativity.
文摘The purpose of this meta-analysis was to evaluate the effects of acute exercise on short-term memory improvement.The computerized literature searches using electronic databases and examinations of reference lists from relevant studies yielded six studies meeting our inclusionary criteria.In a total of six studies,16 standardized regression coefficient effect sizes(ESs)were calculated to be meta-analyzed.The meta-analyses showed a statistically significant increase in short-term memory improvement across both the exercise and non-exercise control groups in trials 1-5[ES=0.96,95%CI(0.95,0.97),P<0.001].However,there was no significant subgroup difference between exercise and control groups(Q_(b)=0.40,df=1,P=0.53).Our meta-analytic review provides suggestive evidence that an acute bout of exercise prior to learning does not result in short-term memory improvement to a greater extent than a non-exercise control.Additional research is needed to further evaluate whether acute exercise enhances long-term memory via enhanced learning and/or post-learning mechanisms.
文摘Purpose The maximal isometric strength test is widely used in general,athletic,and clinical populations.However,this test has often been used without considering how many trials are needed or appropriate to obtain reliable test scores.Thus,the aim of this study was to examine the maximal isometric strength test in upper and lower body for the purpose of determining the reliability of best isometric strength score and the ideal number of trials for a reliable test score.Methods One hundred and twelve healthy adults were assigned to four different groups(elbow flexion with the vertical and horizontal forearm positions,knee flexion,and knee extension).After familiarization,all participants performed three maxi-mal isometric voluntary contractions with the designated muscle group.The reliability of best isometric strength test score was calculated using the intraclass correlation coefficients(ICC)from a one-way ANOVA model.The Spearman-Brown prophecy formula was used to identify the minimum number of trials needed.Results The reliability of the best maximal isometric strength test scores out of three trials were high(ICC=0.92 to 0.98).At least two trials of maximal isometric strength test for knee flexion and one trial for elbow flexion and knee extension would be necessary to achieve an acceptable reliability coefficient of 0.80.In addition,one trial of elbow flexion would be enough for women,but men would need two trials.Conclusions Our results suggest that overall,at least two trials would be necessary to test isometric strength in upper and lower body muscles in both sexes.
