Associations of Sedentary Time and Physical Activity with Metabolic Syndrome among Chinese Adults:Results from the China Health and Nutrition Survey

Objective This study aimed to determine the independent and joint associations of sedentary time(ST)and physical activity(PA) with metabolic syndrome(MetS) and its components among Chinese adults.Methods The study analyzed data from 4,865 adults aged ≥ 18 years who participated in the 2009 and2015 China Health and Nutrition Surveys(CHNS). Four types of leisure ST and three types of PA selfreported at baseline were collected. Multivariable logistic regressions were used to determine the independent and joint associations of ST and PA with the odds of MetS or its components.Results For independent effects, higher levels of television time and total leisure ST was associated with higher MetS risk [odds ratio(OR) 1.3, 95% confidence interval(CI) 1.1–1.6, P < 0.001;OR 1.4, 95% CI1.2–1.8, P < 0.001, respectively]. The MetS risk in the computer time > 7 hours/week(h/w) group was higher than that in the < 7 h/w group in(OR 1.5, 95% CI 1.2–1.9). Higher levels of moderate-to-vigorousintensity physical activity(MVPA) and total PA were associated with a lower MetS risk(OR 0.7, 95% CI0.6–0.9, P < 0.001;OR 0.8, 95% CI 0.7–0.9, P < 0.001, respectively). For the joint effects, compared with those reporting the lowest level of total leisure ST(< 14 h/w) and the most active tertile of MVPA(≥ 61.0 MET-h/w), participants reporting the most total leisure ST(≥ 35 h/w) and the lowest level of MVPA(0 MET-h/w) had the highest odds of MetS(OR 2.0;95% CI 1.4–2.7). Except for people reporting ST(14–21 h/w) within the most active tertile of MVPA, the associations in all other groups were significant.With the increase of TV time and decreased MVPA, the odds of MetS almost showed a curve acceleration.Conclusions MVPA and total PA have independent preventive effects, and sedentary behavior(mainly watching TV) has an unsafe effect on MetS and its components. Strengthening the participation of MVPA and combining the LPA to replace the TV-based ST to increase the total PA may be necessary to reduce the prevalence of MetS in Chinese adults.

A mixed-studies systematic review and meta-analysis of school-based interventions to promote physical activity and/or reduce sedentary time in children

Purpose:The aim of this mixed-studies systematic review was to ascertain the effectiveness of school-based interventions in increasing physical activity(PA) and/or reducing sedentary time(ST) in children aged 5-11 years,as well as to explore their effectiveness in relation to categories of the theory of expanded,extended,and enhanced opportunity(TEO).Methods:Adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA) guidelines,5 databases were searched using predefined search terms.Following title and abstract screening of 1115 records,the removal of duplicates(n=584) and articles that did not meet the inclusion criteria agreed to a priori(n=419) resulted in 112 records that were full-text screened.Two independent reviewers subsequently used the mixed-methods appraisal tool to assess the methodological quality of 57 full-text studies that met the inclusion criteria after full-text screening.The interventions were summarised using the TIDierR checklist and TEO.The strength of evidence was determined using a 5-level rating system utilising a published decision tree.Results:Overall evidence ratings for interventions implemented within school settings were:no evidence of effects on moderate-to-vigorous physical activity(MVPA) and inconclusive evidence of effects on sedentary time.In relation to the TEO,expansion of PA appeared to be the most promising intervention type for MVPA,with moderate evidence of effect,whereas extension and enhancement of PA opportunity demonstrated no evidence of effect.A critical issue of possible compensatory behavior was identified by analysis of intervention effect in relation to PA measurement duration;when studies measured changes in PA during the actual intervention,there was moderate evidence of effect,whereas those that measured changes in PA during the school day presented inconclusive evidence of effect,and those that measured changes in PA over a whole day yielded no evidence of effect.Two meta-analyses of those studies using a whole-day accelerometer measure for MVPA or ST showed a significant but moderate effect for MVPA(effect size=0.51;95% confidence interval(CI):0.02-0.99) and a large but nonsignificant effect for ST(effect size=1.15;95%CI:-1.03 to 3.33);both meta-analyses demonstrated low precision,considerable inconsistency,and high heterogeneity.Conclusion:The findings have important implications for future intervention research in terms of intervention design,implementation,and evaluation.

Physical Activity,Sedentary Behavior,and the Risk of Cardiovascular Disease in Type 2 Diabetes Mellitus Patients:The MIDiab Study

The aim of this study was to explore the associations of moderate-to-vigorous-intensity physical activity(MVPA)time and sedentary(SED)time with a history of cardiovascular disease(CVD)and multifactorial(i.e.,blood pressure(BP),body mass index(BMI),low-density lipoprotein cholesterol(LDL-C),and glycated hemoglobin A1c(HbA1c))control status among type 2 diabetes mellitus(T2DM)patients in China.A cross-sectional analysis of 9152 people with type 2 diabetes from the Multifactorial Intervention on Type 2 Diabetes(MIDiab)study was performed.Patients were grouped according to their self-reported MVPA time(low,<150 min·week−1;moderate,150 to<450 min·week−1;high,≥450 min·week−1)and SED time(low,<4 h·d–1;moderate,4 to<8 h·d–1;high,≥8 h·d–1).Participants who self-reported a history of CVD were identified as having a CVD risk.Odds ratios(ORs)and 95%confidence intervals(CIs)of CVD risk and multifactorial control status associated with MVPA time and SED time were estimated using mixed-effect logistic regression models,adjusting for China’s geographical region characteristics.The participants had a mean±standard deviation(SD)age of(60.87±8.44)years,44.5%were women,and 25.1%had CVD.After adjustment for potential confounding factors,an inverse association between high MVPA time and CVD risk that was independent of SED time was found,whereas this association was not observed in the moderate-MVPA group.A higher MVPA time was more likely to have a positive effect on the control of BMI.Compared with the reference group(i.e.,those with MVPA time≥450 min·week−1 and SED time<4 h·d–1),CVD risk was higher in the low-MVPA group:The OR associated with an SED time<4 h·d–1 was 1.270(95%CI,1.040–1.553)and that associated with an SED time≥8 h·d–1 was 1.499(95%CI,1.149–1.955).We found that a high MVPA time(i.e.,≥450 min·week−1)was associated with lower odds of CVD risk regardless of SED time among patients with T2DM.

Changes in physical activity,sedentary behavior,and self-reported cognitive function in cancer survivors before and during the COVID-19 pandemic:A cross-sectional study

Background Physical activity(PA)and reductions in sedentary behavior(SED)may mitigate cancer-related cognitive impairment.The purpose of this study was to examine(a)the associations between changes in PA,SED,and cognitive function in cancer survivors before and during the coronavirus disease 2019(COVID-19)pandemic;and(b)clinical subgroups that moderate this association.Methods A cross-sectional survey was administered online to adult cancer survivors globally between July and November of 2020.This was a secondary analysis of a cross-sectional survey examining changes in self-reported PA and quality of life in cancer survivors before and during the COVID-19 pandemic.Self-reported Questionnaires assessed moderate-to-vigorous PA(MVPA)using the modified Godin Leisure Time Exercise Questionnaire,cognitive function using the Functional Assessment of Cancer Therapy-Cognitive Function(FACT-Cog)scale,and SED using the Domain-specific Sitting Time questionnaire.Cancer survivors were classified into no change in behavior,desirable change(i.e.,increase MVPA to meet PA guidelines or decrease SED by≥60 min/day),and undesirable change(i.e.,decrease MVPA to<150 min/week or increase SED by≥60 min/day).Analysis of covariance examined differences in FACT-Cog scores across the activity change categories.Planned contrasts compared differences in FACT-Cog scores between cancer survivors with(a)no meaningful change vs.any change,and(b)a desirable change vs.an undesirable change.Results There were no significant differences in FACT-Cog scores across activity-change categories in the full sample of cancer survivors(n=371;age=48.6±15.3 years(mean±SD)).However,cancer survivors who were diagnosed≥5 years ago(t(160)=–2.15,p=0.03)or who received treatment≥5 years ago(t(102)=–2.23,p=0.03)and who had a desirable change in activity reported better perceived cognitive abilities than those who had an undesirable change.Conclusion PA promotion efforts should consider reducing SED in addition to maintaining MVPA in long-term cancer survivors to mitigate cancer-related cognitive impairment during the COVID-19 pandemic.

Evaluation of a School-Based Intervention to Promote Physical Activity and Sport among Young People Aged 11-13 in East London, UK

Due to the alarming increase in overweight/obesity among adolescents in the UK and in response to low levels of PAS （physical activity and sport）, initiatives have been developed to promote PAS in vulnerable groups. The purpose of this study is： （1） to evaluate the effect of one such PAS initiative on 11-13 （n = 913） years old young people＇s PAS patterns and participation; （2） to assess young peoples＇ expectations and perceived benefits of the program; and （3） to make evidenced based recommendations for future interventions. Socio-demographic data, PAS data and perceptions of the program were assessed via questionnaire. Anthropometric data （height, weight, waist circumference） were also measured. Wilcoxon signed-rank tests were used to test for significant differences between baseline and follow-up PAS data. McNemar chi-square tests were used to test for significance between baseline and follow-up expectations data. Wilcoxon signed-rank tests showed a reduction in total PAS （from 39% to 7%） from baseline to follow-up but five sports not currently offered through the national PE （physical education） curriculum （badminton, basketball, volleyball, cricket and rowing） saw an increase in participation. Young people＇s perception of the program was positive, with a significant increase in those reporting the program helped them ＂be more sporty＂ and ＂be more healthy＂ （both significant at P 〈 0.05）. While overall PAS did not increase, sports offered outside of those available as part of the national curriculum for PE were more popular; strengthening the case for further research and supporting the current trend of extending the sports available through PE in schools and school sports to positively contribute to increase in PAS. Future interventions should consider the target population more carefully in the design and implementation of such programs by offering culturally responsive PAS programs.