Associations of daily sedentary behavior,physical activity,and sleep with irritable bowel syndrome:A prospective analysis of 362,193 participants

Background:Irritable bowel syndrome(IBS)substantially affects quality of life and requires early prevention.This study aimed to elucidate the relationships between IBS and daily behaviors,including sedentary behavior(SB),physical activity(PA),and sleep.In particular,it seeks to identify healthy behaviors to reduce IBS risk,which previous studies have rarely addressed.Methods:Daily behaviors were retrieved from self-reported data of 362,193 eligible UK Biobank participants.Incident cases were determined by self-report or health care data according to RomeⅣcriteria.Results:A total of 345,388 participants were IBS-free at baseline,during a median follow-up of 8.45 years,19,885 incident IBS cases were recorded.When examined individually,SB and shorter(≤7 h/day)or longer(>7 h/day)sleep duration were each positively associated with increased IBS risk,and PA was associated with lower IBS risk.The isotemporal substitution model suggested that replacing SB with other activities could provide further protective effects against IBS risk.Among people sleeping≤7 h/day,replacing 1 h of SB with equivalent light PA,vigorous PA,or sleep was associated with 8.1%(95%confidence interval(95%CI):0.901-0.937),5.8%(95%CI:0.896-0.991),and 9.2%(95%CI:0.885-0.932)reduced IBS risk,respectively.For people sleeping>7 h/day,light and vigorous PA were associated with a 4.8%(95%CI:0.926-0.978)and a 12.0%(95%CI:0.815-0.949)lower IBS risk,respectively.These benefits were mostly independent of genetic risk for IBS.Conclusion:SB and unhealthy sleep duration are risk factors for IBS.A promising way to mitigate IBS risk for individuals sleeping≤7 h/day and for those sleeping>7 h/day appears to be by replacing SB with adequate sleep or vigorous PA,respectively,regardless of the genetic predisposition of IBS.

Study on the Influence of New Media on College Students’ Physical Exercise Behavior

New media is becoming an important method to promote physical exercise,and it is also an essential factor affecting the physical exercise behavior of college students.This study takes the influence of new media sports information on college students’physical exercise behavior as the research objective.By using a questionnaire survey and mathematical statistics,545 college students in Shandong Province of China are selected as research samples.Based on the theory of new media exposure,fitness behavior theory,and self-efficacy theory,this study systematically discusses the influence and mechanism of new media exposure on the physical exercise behavior of college students in Shandong Province,so as to help college students improve their physical exercise behavior.

Mechanical behaviors of backfill-rock composites: Physical shear test and back-analysis

The shear behavior of backfill-rock composites is crucial for mine safety and the management of surface subsidence.For exposing the shear failure mechanism of backfill-rock composites,we conducted shear tests on backfill-rock composites under three constant normal loads,compared with the unfilled rock.To investigate the macro-and meso-failure characteristics of the samples in the shear tests,the cracking behavior of samples was recorded by a high-speed camera and acoustic emission monitoring.In parallel with the experimental test,the numerical models of backfill-rock composites and unfilled rock were established using the discrete element method to analyze the continuous-discontinuous shearing process.Based on the damage mechanics and statistics,a novel shear constitutive model was proposed to describe mechanical behavior.The results show that backfill-rock composites had a special bimodal phenomenon of shearing load-deformation curve,i.e.the first shearing peak corresponded to rock break and the second shearing peak induced by the broken of aeolian sand-cement/fly ash paste backfill.Moreover,the shearing characteristic curves of the backfill-rock composites could be roughly divided into four stages,i.e.the shear failure of the specimens experienced:stage I:stress concentration;stage II:crack propagation;stage III:crack coalescence;stage IV:shearing friction.The numerical simulation shows that the existence of aeolian sand-cement/fly ash paste backfill inevitably altered the coalescence type and failure mode of the specimens and had a strengthening effect on the shear strength of backfillrock composites.Based on damage mechanics and statistics,a shear constitutive model was proposed to describe the shear fracture characteristics of specimens,especially the bimodal phenomenon.Finally,the micro-and meso-mechanisms of shear failure were discussed by combining the micro-test and numerical results.The research can advance the better understanding of the shear behavior of backfill-rock composites and contribute to the safety of mining engineering.

Physical Activity and Sedentary Behaviors among Chinese Children: Recent Trends and Correlates

Objective This study was aimed at examining the trends and correlates of physical activity(PA)and sedentary behaviors among Chinese children.Methods A total of 4,341 subjects(6,936 observations)aged 6–17 years who participated in the China Health and Nutrition Survey(2004–2015)were included.Of the subjects,41%participated in the survey twice or more.Random-effects ordinal regression models and repeated-measures mixed-effects models were used to examine the PA trends.Quantile regression models were applied to examine the factors influencing PA and sedentary behaviors.Results From 2004 to 2015,the prevalence of physical inactivity among Chinese children aged 6–17 years increased by 5.5%[odds ratio(OR),1.51;95%confidence interval(CI),1.19–1.90;P<0.001].The PA volume declined by 5.8 metabolic equivalent of task-hr/week(P<0.001),and the time spent in sedentary behaviors increased by 1.8 hr/week(P<0.001).Age,ethnicity,and region showed significant effects on the PA volume across the quartiles(P<0.001).Across the quartiles,sedentary time was significantly higher in the children residing in urban areas(P<0.001)or areas with high urbanization levels(P≤0.005)than in their counterparts.Conclusions A declining PA trend among Chinese children aged 6–17 years was observed from 2004 to2015,and certain subgroups and geographical areas are at higher risk of physical inactivity.

Physical activity,sedentary behaviors,physical fitness,and their relation to health outcomes in youth with type 1 and type 2 diabetes:A review of the epidemiologic literature

Diabetes is a leading chronic disease of childhood and adolescence. In addition to the well-known auto-immune, insulin-dependent diabetes mellitus （type 1 diabetes （T 1D））, the past two decades have witnessed the emergence of type 2 diabetes （T2D） in children and adolescents, which previously was only seen in middle-aged or older adults. One of the key components of diabetes management is physical activity （PA）. The beneficial effects of increased PA and decreased sedentary behavior are extremely important in youth with diabetes because of the markedly increased long-term risk of cardiovascular disease in this population compared to persons without diabetes. This review aims to comprehensively summarize the epidemiologic, observational research published and listed in PubMed between 1970 and 2012 on PA and sedentary behaviors, as well as physical fitness in children and adolescents with T1D and T2D. Additionally, we describe briefly the state of knowledge on perceived barriers of PA in persons with diabetes, with a focus on hypoglycemia. Finally, we provide an overview of the epidemiological literature pertaining to health benefits of increased PA in youth with TID and T2D and briefly discuss the topic of exercise-related hypoglycemia, Copyright ~ 2012, Shanghai University of Sport. Production and hosting by Elsevier B.V. All rights reserved.

Replacement of leisure-time sedentary behavior with various physical activities and the risk of dementia incidence and mortality:A prospective cohort study

Background:Whether or not there is targeted pharmacotherapy for dementia,an active and healthy lifestyle that includes physical activity(PA)may be a better option than medication for preventing dementia.We examined the association between leisure-time sedentary behavior(SB)and the risk of dementia incidence and mortality.We further quantified the effect on dementia risk of replacing sedentary time with an equal amount of time spent on different physical activities.Methods:In the UK Biobank,484,169 participants(mean age=56.5 years;45.2%men)free of dementia were followed from baseline(2006-2010)through July 30,2021.A standard questionnaire measured individual leisure-time SB(watching TV,computer use,and driving)and PA(walking for pleasure,light and heavy do-it-yourself activity,strenuous sports,and other exercise)frequency and duration in the 4 weeks prior to evaluation.Apolipoprotein E(APOE)genotype data were available for a subset of 397,519(82.1%)individuals.A Cox proportional hazard model and an isotemporal substitution model were used in this study.Results:During a median 12.4 years of follow-up,6904 all-cause dementia cases and 2115 deaths from dementia were recorded.In comparison to participants with leisure-time SB<5 h/day,the hazard ratio((HR),95%confidence interval(95%CI))of dementia incidence was 1.07(1.02-1.13)for 5-8 h/day and 1.25(1.13-1.38)for>8 h/day,and the HR of dementia mortality was 1.35(1.12-1.61)for>8 h/day.A 1 standard deviation increment of sedentary time(2.33 h/day)was strongly associated with a higher incidence of dementia and mortality(HR=1.06,95%CI:1.03-1.08 and HR=1.07,95%CI:1.03-1.12,respectively).The association between sedentary time and the risk of developing dementia was more profound in subjects<60 years than in those>60 years(HR=1.26,95%CI:1.00-1.58 vs.HR=1.21,95%CI:1.08-1.35 in>8 h/day,p for interaction=0.013).Replacing 30 min/day of leisure sedentary time with an equal time spent in total PA was associated with a6%decreased risk and 9%decreased mortality from dementia,with exercise(e.g.,swimming,cycling,aerobics,bowling)showing the strongest benefit(HR=0.82,95%CI:0.78-0.86 and HR=0.79,95%CI:0.72-0.86).Compared with APOEε4 noncarriers,APOEε4 carriers are more likely to see a decrease in Alzheimer’s disease incidence and mortality when PA is substituted for SB.Conclusion:Leisure-time SB was positively associated with the risk of dementia incidence and mortality.Replacing sedentary time with equal time spent doing PA may be associated with a significant reduction in dementia incidence and mortality risk.

Understanding Chinese international college and university students' physical activity behavior

Objective： To examine factors of the youth physical activity promotion （YPAP） model that are associated with Chinese international students＇ meeting PA recommendations （MPAR）. Methods： A total of 649 （females = 320, males = 329） Chinese international college students participated in the study. This study was conducted in the United States （US.） between June and August in 2011. Participants completed an online survey regarding their demographic, PA, predisposing, enabling, and reinforcing factors. Results： Logistic nested-regression analysis suggested that being male, having a higher body mass index, perceived competence, self-efficacy, attitude, and enjoyment all increased （p 〈 0.001） the participants＇ odds of MPAR. Except language barriers, all of the enabling and reinforcing factors predicted MPAR indirectly through the predisposing factors （p 〈 0.001）. Conclusion： Understanding factors that influence PA among Chinese international students is an important step in the process of promoting their long-term health and wellbeing. Designing program that address the identified key factors may help colleges and universities achieve this goal.

BEHAVIOR OF OXYGEN IN DG^(TM) INVAR-Cu ALLOYS AND ITS EFFECTS ON MECHANICAL AND PHYSICAL PROPERTIES

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Investigating College Students’ Diet and Physical Activity Behaviors Regarding Non-Communicable Diseases Prevention in China

We aimed to investigate if college students’ dietary and physical activity adhered to the Chinese Dietary Guidelines, the Composing Editorial Board of Physical Activity Guidelines, and WHO recommendation for NCDs prevention. Methods: A 3-day (2 weekdays and 1 weekend day) 24-hour (24-HRs) dietary recall was conducted to record details of participants’ food consumption. One-way analysis of variance (ANOVA) was applied to examine the influence of the identified demographic variables (including BMI, gender, major, family monthly income, and place of household registration) on the 8 food groups’ consumption. We analyzed the effect of the various demographic variables on sodium intake by the student’s t-test. The questionnaire, International Physical Activity Questionnaire (IPAQ)-Short Form, was utilized to assess participants’ physical activity (PA) level. The Wilcoxon-Mann-Whitney was applied to analyze participants’ physical activity. Results: Our research indicated participants consumed much fewer fruits and vegetables and excessive meats on average for both males and females regarding NCDs prevention. Conclusion: Participants’ dietary intake did not comply with the Chinese Dietary Guide-lines recommendation for chronic diseases prevention. Nutrition knowledge and health education are needed for college students. .

Correlation and pathways of behavioral activation systems mediating physical activity level and depressive symptoms among college students

BACKGROUND Depression is a common mental disorder among college students.The main symptoms include being persistent low mood,sad emotional experiences,lack of pleasure,listlessness,and impaired cognitive function accompanied by tendencies of self-harm and suicide.AIM To clarify the pathways and effects of the behavioral activation system between physical activity and depressive symptoms in college students with depressive symptoms.METHODS This cross-sectional research screened 3047 college students.Of these,472 had depressive symptoms,with a depression detection rate of 15.49%.Furthermore,442 college students with depressive symptoms were analyzed.A one-way analysis of variance and Pearson’s correlation,linear regression,and structural equation modeling analyses were used to explore the correlations and pathways of the interactions between the variables.RESULTS Depressive symptoms were significantly negatively correlated with physical activity(r=-0.175,P<0.001),the behavioral activation system(r=-0.197,P<0.001),and drive(r=-0.113,P=0.017).Furthermore,it was negatively correlated with fun-seeking(FS)(r=-0.055,P=0.251);however,it was not significant.Physical activity was significantly positively correlated with reward responsiveness(RR)(r=0.141,P=0.003)and drive(r=0.124,P=0.009)and not significantly positively correlated with FS(r=0.090,P=0.058).The mediating effect of RR between physical activity and depressive symptoms was significant[B=-0.025,95%confidence interval(95%CI):-0.051 to-0.008,P=0.001].The direct and total effects of physical activity on depressive symptoms and were significant(B=-0.150,95%CI:-0.233 to-0.073,P<0.001;B=-0.175,95%CI:-0.260 to-0.099,P<0.001),respectively.CONCLUSION As physical activity levels increased,depression scores among college students decreased.The mediating effect of RR between physical activity and depressive symptoms was significant.Therefore,colleges and universities should encourage college students with depression to increase their physical activity and improve their behavioral activation system.Particular attention should be paid to RR,which may reduce the prevalence of depressive symptoms.

The Effects of a Lifestyle Modification Program on a Leisure Physical Activity and Sedentary Behavior in a Brazilian Low Socioeconomic Community

Regular physical activity benefits the health of the general population, more in those with sedentary behaviors. PURPOSE： To verify the impact of adding leisure-time activities to the existed sedentary behaviors. METHODS： A cross-sectional and a longitudinal analysis were undertaken in an ongoing epidemiological study （＂Move for Health＂） conducted by this Institution. The longitudinal study comprised 1572 subjects older than 35 yrs （53.8 ± 11.1 yrs, 76% women） enrolled during the period of 2004 to 2015. After a baseline assessment, the participants were submitted to a 10-week program of supervised physical exercises training and dietary counseling. The physical exercise protocol was composed by daily sessions （100 min）, 3-5x/wk, including warm up/stretching （20min）, 30 rain walking （60%-80% VO2max）, 40min strength in academy （3x 8-12 rep, 60%-70% 1RM） and stretching and cool down （10 min）. By using the International Physical Activity Questionnaire （IPAQ-way long-version 8）, it was evaluated the time spent on sedentary activities during the week and on weekends （h/day）, in the domains of sedentary transport （h/week） and physical leisure activities （h/week） at baseline （M0） and after 10 weeks （MI） of physical intervention. The Student＇s t test was used to compare moments with a significance level of 5%. RESULTS： I was shown that 18.3% presented lower values than 150 min/wk of physical activity. Lower quartile of leisure domain on weekdays along with more sedentary behavior on weekends were determined by socioeconomic characteristics such as lower income and schooling. The sample referred low income （71% earning less than 5 minimum salary wage）, low schooling （52.6% uncompleted elementary school） but in a good-excellent status of health, according their self-perception. Leisure time-physical activity increased 2.12 （P 〈 0.001）. Behaviors of sedentary transport and sitting time either weekdays or weekends did not change significantly （P 〉 0.05）. CONCLUSION： An inexpensive and institutional-conducted lifestyle modification program like the ＂Move for Health＂ can provide extra energy expenditure, as leisure time, to a low socioeconomic community. However, it has been unsuccessfully proved to change other existing sedentary behavior.

The Application of Theoretical Models in the Studies of Physical Activity Behaviors of the Elderly in China

By using the method of literature review, this paper introduces the popular theoretical models which have shown to better explain physical activity behaviors at a certain degree, summarizes the dominating theoretical models in the studies of physical activity behaviors of the elderly in China. In addition, shortcomings and future prospects are pointed out at the end.

Effect of physical activity on healthcare seeking behavior in the general Chinese population:an urban-rural perspective

Background:The“two-week visiting rate in those needing to visit”has been examined extensively as an important indicator of healthcare seeking behavior in China.Nevertheless,its relationship with health behaviors,such as physical activity,remains unknown.In addition,a significant difference exists between urban and rural Chinese people in terms of physical activity and healthcare seeking behavior.This study sought to investigate the relationship between physical activity and the two-week visiting rate by conducting a stratified analysis.Methods:The analysis included 5,801 participants aged above 15 years old.Multivariable logistic regression was applied to analyze the association after adjusting for possible confounding variables.Urban and rural differences were investigated using stratified analysis.Results:Adjusted estimates showed that those who were physically active were more likely to visit a healthcare facility,but only among the whole sample(adjusted odds ratio(AOR)=1.45,95%confidence interval(CI):1.26.1.66)and the rural sample(AOR=1.56,95%CI:1.21.2.01),and not among the urban sample.Conclusions:Educating people on physical activity may help in improving healthcare seeking behavior and vice versa.Additionally,health interventions may be tailored based on different settings.

Reviving Direct Observation Methods for Physical Activity Behavior

Purpose:Current Direct Observation(DO)methods are burdensome to the observer and relevant limitations can be identified on the outcome information.This study aims to characterize DO from the observers’point of view and to analyze the feasibility and usefulness of visual information in the form of video.Method:data collection was done with ten adult males,observed while performing different physical activities in an indoor court.Sessions were video recorded by two cameras.Three observers performed systematic observation,using SOPLAY,with different sampling rates.Inter observer’s agreement and with reference data was analyzed by Cohen’s Kappa statistic.Results:SOPLAY highest agreement between observers was 0.611 on vigorous category and walking category had the lowest 0.188.It doubles the time needed to annotate the video with pauses,but half of player’s behavior is preserved.Conclusion(s):using video to support DO permits to collect more accurate data and a more detailed behavior categorization is warranted.Developments in computer vision are expected to reduce the human efforts in DO methods.

Information behaviors of Chinese K-12physical education teachers:A survey study

Purpose: Given the unique characteristics of physical education(PE) teaching in K-12education,PE teachers' information behaviors deserve special attention.This article reports a survey study of PE teachers' information behaviors,covering information literacy skills and behaviors of information seeking and information use.Design/methodology/approach:A questionnaire survey was conducted of K-12 PE teachers in the Tianjin municipal region of China,with a response rate of 61.9%.Findings:PE teachers lack skills with information retrieval systems in general.The Internet continues to be their primary information source,and they rely more on personal collection and colleagues than the school library for teaching materials.They rarely develop a searching strategy,employ querying tactics,or use advanced search functions,and they tend to be content with finding a few relevant articles.Research limitations:The survey is limited to the Tianjin municipal region in scope.Though attempting to reach 210 participants from 40 schools,it yielded only 130 valid responses.A larger survey covering more regions and with greater responses may be useful.Practical implications:Insights from this study inform the educational and on-job training of K-12 PE teachers to improve their information literacy skills.Originality/value:Little research exists on PE teachers' behaviors of information seeking.This study bridges the gap and enriches our understanding of K-12 teachers' information behaviors.

Effect of Gd Addition on Hot Deformation Behavior and Microstructure Evolution of 7075 Aluminum Alloy

In order to clarify the effect of rare earth Gd on the microstructure evolution and deformation behavior of 7075 aluminum alloy during hot compression,uniaxial compression tests of Al-Zn-Mg-Cu-0.5%Gd were conducted at strain rates of 0.001,0.01,0.1,and 1 s^(-1)with the temperatures ranging from 350 to 450℃.The microstructural evolution during deformation was characterized using optical microscopy and electron backscatter diffraction(EBSD)techniques.The experimental results indicate that the addition of the rare earth element Gd significantly increases the peak flow stress and thermal activation energy of the alloy.Due to the pinning effect of rare earth phases,dislocation movement is hindered,leading to an increased level of work hardening in the alloy.However,the dynamic recrystallization of the alloy is complicated.At a high Z(Zener-Hollomon parameter)values,recrystallization occurs in the form of DDRX(Discontinuous Dynamic Recrystallization),making it easier to nucleate at grain boundaries.As the Z value decreases gradually,the recrystallization mechanism transitions from discontinuous dynamic recrystallization(DDRX)to continuous dynamic recrystallization(CDRX).At a low Z values with the strain rate of 0.001 s^(-1),the inhibitory effect of rare earths weakens,resulting in a comparable recrystallization ratio between Al-Zn-Mg-Cu-Gd alloy and 7075 aluminum alloy.Moreover,the average grain size of the aluminum alloy with Gd addition is only half that of 7075 aluminum.The addition of Gd provides Orowan and substructure strengthening for the alloy,which greatly improves the work-hardening of the alloy compared with 7075 aluminum alloy and improves the strength of the alloy.

Prediction of Hot Deformation Behavior of 7Mo Super Austenitic Stainless Steel Based on Back Propagation Neural Network

The hot compression tests of 7Mo super austenitic stainless(SASS)were conducted to obtain flow curves at the temperature of 1000-1200℃and strain rate of 0.001 s^(-1)to 1 s^(-1).To predict the non-linear hot deformation behaviors of the steel,back propagation-artificial neural network(BP-ANN)with 16×8×8 hidden layer neurons was proposed.The predictability of the ANN model is evaluated according to the distribution of mean absolute error(MAE)and relative error.The relative error of 85%data for the BP-ANN model is among±5%while only 42.5%data predicted by the Arrhenius constitutive equation is in this range.Especially,at high strain rate and low temperature,the MAE of the ANN model is 2.49%,which has decreases for 18.78%,compared with conventional Arrhenius constitutive equation.

Determination of local constitutive behavior and simulation on tensile test of 2219-T87 aluminum alloy GTAW joints

The local and global mechanical responses of gas tungsten arc welds（GTAW） of a 2219-T87 aluminum alloy were investigated with experiment and numerical simulation.Digital image correlation（DIC） was used to access the local strain fields in transversely loaded welds and to determine the local stress-strain curves of various regions in the joint.The results show that the DIC method is efficient to acquire the local stress-strain curves but the curves of harder regions are incomplete because the stress and strain ranges are limited by the weakest region.With appropriate extrapolation,the complete local stress-strain curves were acquired and proved to be effective to predict the tensile behavior of the welded joint.During the tensile process,the fracture initiates from the weld toes owing to their plastic strain concentrations and then propagates along the fusion line,finally propagates into the partially melted zone（PMZ）.

Study protocol: A national cross-sectional study on psychology and behavior investigation of Chinese residents in 2023

Introduction:This study protocol specifies the primary research line and theoretical framework of the 2023 Survey of the Psychology and Behavior of the Chinese Population.It aims to establish a consistent database of Chinese residents'psychological and behavioral surveys through multi-center and large-sample cross-sectional surveys to provide robust data support for developing research in related fields.It will track the public's physical and psychological health more comprehensively and systematically.Methods:The study was conducted from June 20,2023 to August 31,2023,using stratified and quota sampling methods.A total of 150 cities across 800 communities/villages were surveyed,selected from China(Despite extensive coordination,we have been unable to contact our counterparts in the Taiwan region of China to obtain relevant statistical data).The questionnaires were distributed to the public one-on-one and face-to-face by trained surveyors.The questionnaires included basic information about the individual,personal health status,basic information about the family,the social environment in which the individual lives,psychological condition scales,behavioral level scales,other scales,and attitudes towards topical social issues.Supervisors conducted quality control during the distribution process and returned questionnaires,logically checked and cleaned for data analysis.Discussion:Data collection has been finished,and scientific outputs based on this data will support the development of health promotion strategies in China and globally.In the aftermath of the pandemic,it will guide policymakers and healthcare organizations to improve their existing policies and services to maximize the physical and mental health of the Chinese population.Trial Registration:This study was filed in the National Health Security Information Platform(Record No.:MR-37-23-017876)and officially registered in the China Clinical Trials Registry(Registration No.:ChiCTR2300072573).

Hot deformation behavior and processing maps of Mg-Zn-Cu-Zr magnesium alloy

The deformation behaviors of a new quaternary Mg-6Zn-1.5Cu-0.5Zr alloy at temperatures of 523-673 K and strain rates of 0.001-1 s-1 were studied by compressive tests using a Gleeble 3800 thermal-simulator.The results show that the flow stress increases as the deformation temperature decreases or as the strain rate increases.A strain-dependent constitutive equation and a feed-forward back-propagation artificial neural network were used to predict flow stress,which showed good agreement with experimental data.The processing map suggests that the domains of 643-673 K and 0.001-0.01 s-1 are corresponded to optimum conditions for hot working of the T4-treated Mg-6Zn-1.5Cu-0.5Zr alloy.