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Association of daily sitting time and leisure-time physical activity with body fat among U.S.adults 被引量:1
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作者 Jingwen Liao Min Hu +4 位作者 Kellie Imm Clifton J.Holmes Jie Zhu Chao Cao Lin Yang 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第2期195-203,共9页
Background:Prolonged sitting and reduced physical activity lead to low energy expenditures.However,little is known about the joint impact of daily sitting time and physical activity on body fat distribution.We investi... Background:Prolonged sitting and reduced physical activity lead to low energy expenditures.However,little is known about the joint impact of daily sitting time and physical activity on body fat distribution.We investigated the independent and joint associations of daily sitting time and physical activity with body fat among adults.Methods:This was a cross-sectional analysis of U.S.nationally representative data from the National Health and Nutrition Examination Survey2011-2018 among adults aged 20 years or older.Daily sitting time and leisure-time physical activity(LTPA)were self-reported using the Global Physical Activity Questionnaire.Body fat(total and trunk fat percentage)was determined via dual X-ray absorptiometry.Results:Among 10,808 adults,about 54.6%spent 6 h/day or more sitting;more than one-half reported no LTPA(inactive)or less than 150 min/week LTPA(insufficiently active)with only 43.3%reported 150 min/week or more LTPA(active)in the past week.After fully adjusting for sociodemographic data,lifestyle behaviors,and chronic conditions,prolonged sitting time and low levels of LTPA were associated with higher total and trunk fat percentages in both sexes.When stratifying by LTPA,the association between daily sitting time and body fat appeared to be stronger in those who were inactive/insuufficiently active.In the joint analyses,inactive/insuufficiently active adults who reported sitting more than 8 h/day had the highest total(female:3.99%(95%confidence interval(95%CI):3.09%-4.88%);male:3.79%(95%CI:2.75%-4.82%))and trunk body fat percentages(female:4.21%(95%CI:3.09%-5.32%);male:4.07%(95%CI:2.95%-5.19%))when compared with those who were active and sitting less than 4 h/day.Conclusion:Prolonged daily sitting time was associated with increased body fat among U.S.adults.The higher body fat associated with 6 h/day sitting may not be offset by achieving recommended levels of physical activity. 展开更多
关键词 ADULTS Body fat distribution Physical activity Sitting time
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Cross-Lagged Relationship between Physical Activity Time,Openness and Depression Symptoms among Adolescents:Evidence from China 被引量:4
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作者 Xiaojie Cao Qinyu Zhang Xinqiao Liu 《International Journal of Mental Health Promotion》 2023年第9期1009-1018,共10页
The relationship between physical activity time,openness and depression symptoms among adolescents is a cutting-edge research direction in the field,yet it remains unclear.This study is based on a sample of 7924 stude... The relationship between physical activity time,openness and depression symptoms among adolescents is a cutting-edge research direction in the field,yet it remains unclear.This study is based on a sample of 7924 students from a nationally representative China Education Panel Survey database and examines the bidirectional relationships between physical activity time,openness and depression symptoms among Chinese adolescents.Descriptive analysis showed that during the 7th and 8th grades,the average physical activity time decreased to less than one hour per day,accompanied by a decreasing trend in openness and a slight worsening in depression symptoms.Correlation analysis showed a significant negative correlation between physical activity time and depression symptoms,a significant positive correlation between physical activity time and openness,and a significant negative correlation between depression symptoms and openness.The results from cross-lagged models indicated a bidirectional relationship between physical activity time and openness,with physical activity time significantly positively predicting openness in the following year and openness significantly positively predicting physical activity time in the following year.In addition,depression symptoms had a unidirectional negative predictive effect on openness.The conclusions provide empirical evidence for education administration and schools to promote the physical and mental health development of adolescents worldwide. 展开更多
关键词 Physical activity time DEPRESSION OPENNESS adolescents
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River width and depth as key factors of diurnal activity energy expenditure allocation for wintering Spot-billed Ducks in the Xin'an River Basin
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作者 Chao Yu Xuying Lu +3 位作者 Deli Sun Mengnan Chu Xueyun Li Qun Li 《Avian Research》 SCIE CSCD 2024年第1期116-122,共7页
Rivers are important habitats for wintering waterbirds.However,they are easily influenced by natural and human activities.An important approach for waterbirds to adapt to habitats is adjusting the activity time and en... Rivers are important habitats for wintering waterbirds.However,they are easily influenced by natural and human activities.An important approach for waterbirds to adapt to habitats is adjusting the activity time and energy expenditure allocation of diurnal behavior.The compensatory foraging hypothesis predicts that increased energy expenditure leads to longer foraging time,which in turn increases food intake and helps maintain a constant energy balance.However,it is unclear whether human-disturbed habitats result in increased energy expenditure related to safety or foraging.In this study,the scan sample method was used to observe the diurnal behavior of the wintering Spot-billed Duck(Anas poecilorhyncha) in two rivers in the Xin’an River Basin from October 2021 to March 2022.The allocation of time and energy expenditure for activity in both normal and disturbed environments was calculated.The results showed that foraging accounted for the highest percentage of time and energy expenditure.Additionally,foraging decreased in the disturbed environment than that in the normal environment.Resting behavior showed the opposite trend,while other behaviors were similar in both environments.The total diurnal energy expenditure of ducks in the disturbed environment was greater than that in the normal environment,with decreased foraging and resting time percentage and increased behaviors related to immediate safety(swimming and alert) and comfort.These results oppose the compensatory foraging hypothesis in favor of increased security.The optimal diurnal energy expenditure model included river width and water depth,which had a positive relationship;an increase in either of these two factors resulted in an increase in energy expenditure.This study provides a better understanding of energy allocation strategies underlying the superficial time allocation of wintering waterbirds according to environmental conditions.Exploring these changes can help understand the maximum fitness of wintering waterbirds in response to nature and human influences. 展开更多
关键词 Diurnal behavior activities River factors time and energy expenditure allocation Wintering Spot-billed Duck Xin’an River Basin
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Diurnal activity rhythms and time budgets of captive Qinling golden takin(Budorcas taxicolor bedfordi) in the Qinling Mountains,Shaanxi,China 被引量:2
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作者 陈炜 申琦 +2 位作者 马清义 潘广林 雷初朝 《Journal of Forestry Research》 SCIE CAS CSCD 2007年第2期149-152,共4页
In July 2006, the diurnal activity rhythms of 13 heads of captive Qinling golden takin were observed in Shaanxi Provincial Centre for the Breeding and Conservation of Rare Wildlife (SPCBCRW) at daylight (from 9:00... In July 2006, the diurnal activity rhythms of 13 heads of captive Qinling golden takin were observed in Shaanxi Provincial Centre for the Breeding and Conservation of Rare Wildlife (SPCBCRW) at daylight (from 9:00 am to 4:00 pm in July). The behavioral ethnogram was identified through observation at the sampling site, with the behaviors of golden takin recorded at 5 min interval using instantaneous scannable sampling method. The results indicated that the resting of golden takin took an important part in the daylight activities. Meanwhile, drinking and urinating and defecating were 1.92 and 0.54 and 0.92 times per head per day. Ambient temperature had a strong effect on the diurnal activity rhythms of golden takin. The diurnal activity rhymes were affected by ages of the animals effectively, which was expressed through differentiation of the time budgets. Moreover, different individuals in the same population showed some non-synchronously activity rhythms. 展开更多
关键词 CAPTIVITY Diurnal activity rhythm Golden takin Budorcas taxicolor bedfordi time budget
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Physical Activity,Sedentary Behavior,and the Risk of Cardiovascular Disease in Type 2 Diabetes Mellitus Patients:The MIDiab Study 被引量:1
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作者 Yafei Wu Guijun Qin +32 位作者 Guixia Wang Libin Liu Bing Chen Qingbo Guan Zhongshang Yuan Xu Hou Ling Gao Chao Xu Haiqing Zhang Xu Zhang Qiu Li Yongfeng Song Fei Jing Shizhan Ma Shanshan Shao Meng Zhao Qingling Guo Nanwei Tong Hongyan Zhao Xiaomin Xie Chao Liu Zhongyan Shan Zhifeng Cheng Xuefeng Yu Shulin Chen Tao Yang Yangang Wang Dongmei Li Zhaoli Yan Lixin Guo Qiuhe Ji Wenjuan Wang Jiajun Zhao 《Engineering》 SCIE EI CAS CSCD 2023年第1期26-35,共10页
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 pre... 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. 展开更多
关键词 Type 2 diabetes Physical activity Sedentary time Car diovascular disease
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Twelve weeks of dance exergaming in overweight and obese adolescent girls:Transfer effects on physical activity,screen time,and self-efficacy 被引量:9
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作者 Amanda E.Staiano Robbie A.Beyl +2 位作者 Daniel S.Hsia Peter T.Katzmarzyk Robert L.Newton Jr 《Journal of Sport and Health Science》 SCIE 2017年第1期4-10,127,共8页
Background: Given the low levels of physical activity(PA) among adolescent girls in the US, there is a need to identify tools to motivate increased PA. Although there is limited evidence that adolescents transfer PA f... Background: Given the low levels of physical activity(PA) among adolescent girls in the US, there is a need to identify tools to motivate increased PA. Although there is limited evidence that adolescents transfer PA from one context to another, exergames(i.e., video games that require gross motor activity) may act as a gateway to promote overall PA outside game play. The purpose of this study was to examine potential transfer effects(i.e., influences on external behaviors and psychological constructs) of a 12-week exergaming intervention on adolescent girls' PA, screen time,and self-efficacy toward PA, as well as the intrinsic motivation of exergaming.Methods: Participants were 37 girls aged 14–18 years(65% African American, 35% white) who were overweight or obese(body mass index ≥ 85 th percentile) and were recruited from the community via school, physicians, news media, and social media websites. Adolescents were randomly assigned to a 12-week group exergaming intervention(thirty-six 60 min sessions of group-based dance exergaming in a research laboratory using Kinect for Xbox360(Microsoft Corporation, Redmond, WA, USA)) or to a no-treatment control group. Outcome variables included objectively measured PA(total) and self-reported leisure-time PA(discretionary time only) 1 week before vs. 1 week after the intervention; selected type and intensity of PA when placed in a gym setting for 30 min("cardio free choice"); screen time; self-efficacy toward PA; and intrinsic motivation toward exergaming.Results: Attendance at the exergaming sessions was high(80%). Compared with the control group, the intervention group self-reported an increase in PA(p = 0.035) and fewer hours watching television or videos(p = 0.01) after the intervention, but there were no significant differences in sedentary, light, moderate, or vigorous PA measured by accelerometry. The intervention group significantly improved self-efficacy toward PA(p = 0.028). The intervention group highly rated intrinsic motivation toward exergaming.Conclusion: Exergaming for 12 weeks was associated with positive impacts on adolescent girls' self-reported PA, television viewing, self-efficacy,and intrinsic motivation. Future research is warranted to leverage exergames as an enjoyable, motivating, and effective PA tool. 展开更多
关键词 active video games Leisure activity Motivation Screen time SELF-EFFICACY Television
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Physical activity, screen time and pediatric health-related quality of life in the Mississippi Delta 被引量:3
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作者 Tamara T. Perry Page C. Moore +2 位作者 Karen M. Redwine James M. Robbins Judith L. Weber 《Open Journal of Preventive Medicine》 2012年第1期105-111,共7页
Background: The association of physical activity (PA) and screen time (ST) on health-related quality of life (HRQOL) among predominantly low-income children in the Mississippi Delta region has not been previously desc... Background: The association of physical activity (PA) and screen time (ST) on health-related quality of life (HRQOL) among predominantly low-income children in the Mississippi Delta region has not been previously described. Methods: We performed a cross-sectional survey to assess health risks from a representative sample of the population ≥3 years old in the Delta Region of Arkansas, Louisiana, and Mississippi. Linear models were utilized to examine Pediatric Quality of Life Inventory (PedsQL) scores based on reported PA and ST. Results: Median age of the 371 participants was 9.8 years, 57% were African American, and 26% had annual household income ≤$14,999. Overall, 262 (75%) were categorized as physically active and 48% reported >2 hours ST per day. Children reporting exercising 5 - 7 days per week had significantly better PedsQL total score (84.3 vs 80.8;p 2 hours per day) did not significantly impact HRQOL. Conclusions: Findings suggest that PA among children living in the Mississippi Delta was related to higher HRQOL;however, the positive effects of PA on HRQOL may be less for minority and low-income children. 展开更多
关键词 PHYSICAL activity SCREEN time Quality of LIFE PEDIATRICS
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A mixed-studies systematic review and meta-analysis of school-based interventions to promote physical activity and/or reduce sedentary time in children 被引量:2
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作者 Michelle Jones Emmanuel Defever +2 位作者 Ayland Letsinger James Steele Kelly A Mackintosh 《Journal of Sport and Health Science》 SCIE 2020年第1期3-17,102,共16页
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 yea... 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. 展开更多
关键词 CHILDREN INTERVENTION Physical activity SCHOOL Sedentary time
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Colon transit time according to physical activity and characteristics in South Korean adults 被引量:1
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作者 Kang Ok Cho Yun Ju Jo +2 位作者 Bong Kil Song Jung Woo Oh Yeon Soo Kim 《World Journal of Gastroenterology》 SCIE CAS 2013年第4期550-555,共6页
AIM:To investigate factors contributing to the colon transit time(CTT),physical activity and characteristics were examined.METHODS:Forty-seven Korean adults(males,n=23;females,n=24) took a capsule containing 20 radioo... AIM:To investigate factors contributing to the colon transit time(CTT),physical activity and characteristics were examined.METHODS:Forty-seven Korean adults(males,n=23;females,n=24) took a capsule containing 20 radioopaque markers to measure the CTT.The subjects used an accelerometer to measure the physical activity and underwent a bioelectrical impedance analysis to determine the physical characteristics.Macro-nutrient was also surveyed.RESULTS:The mean total CTTs(TCTT) in the males and females were 8.8 and 24.7 h(P=0.002),respectively.In the male subjects,the right CTT(3.5±4.9 h vs 10.0±11.6 h,P=0.023) and recto-sigmoid CTT(4.4±4.7 vs 13.6±12.5 h,P=0.004) were significantly shorter and the total energy expenditure(637.6±44.3 kcal vs 464.3±64.9 kcal,P=0.003),total activity count(247 017±75 022 count vs 178 014±75 998 count,P=0.003),energy expenditure of light intensity(148.5±6.9 kcal vs 120.0±16.8 kcal,P=0.006),energy expenditure of moderate intensity(472.0±36.2 kcal vs 281.4±22.2 kcal,P < 0.001),fat intake(65.5±23.3 g vs 51.2±17.4 g,P=0.010),and water consumption(1714.3±329.4 g vs 1164.7±263.6 g,P=0.009) were significantly higher than in the female subjects.Regarding correlations,when adjusted for gender,fiber(r =-0.545,P < 0.001) and water intake(r =-0.257,P < 0.05) correlated significantly with the TCTT in all subjects.In addition,the body mass index(r =-0.424,P < 0.05) and fiber intake(r =-0.417,P < 0.05) in the males as well as the fiber intake(r =-0.655,P < 0.001) in the females showed significant correlations with the TCTT.CONCLUSION:The subjects showed significant gender differences in the TCTT,right CTT,and recto-sigmoid CTT.Furthermore,the intake of the fiber and water contributed to the CTT. 展开更多
关键词 COLON TRANSIT time Physical activity CHARACTERISTICS Macro-nutrient SOUTH KOREAN
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Associations of Sedentary Time and Physical Activity with Metabolic Syndrome among Chinese Adults:Results from the China Health and Nutrition Survey 被引量:2
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作者 BAI Jing WANG Yun +5 位作者 ZHANG Xian Fan OUYANG Yi Fei ZHANG Bing WANG Zhi Hong DU Shu Fa WANG Hui Jun 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2021年第12期963-975,共13页
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 ana... 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. 展开更多
关键词 Sedentary time Physical activity Metabolic syndrome ADULTS
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Modified Wild Horse Optimization with Deep Learning Enabled Symmetric Human Activity Recognition Model
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作者 Bareen Shamsaldeen Tahir Zainab Salih Ageed +1 位作者 Sheren Sadiq Hasan Subhi R.M.Zeebaree 《Computers, Materials & Continua》 SCIE EI 2023年第5期4009-4024,共16页
Traditional indoor human activity recognition(HAR)is a timeseries data classification problem and needs feature extraction.Presently,considerable attention has been given to the domain ofHARdue to the enormous amount ... Traditional indoor human activity recognition(HAR)is a timeseries data classification problem and needs feature extraction.Presently,considerable attention has been given to the domain ofHARdue to the enormous amount of its real-time uses in real-time applications,namely surveillance by authorities,biometric user identification,and health monitoring of older people.The extensive usage of the Internet of Things(IoT)and wearable sensor devices has made the topic of HAR a vital subject in ubiquitous and mobile computing.The more commonly utilized inference and problemsolving technique in the HAR system have recently been deep learning(DL).The study develops aModifiedWild Horse Optimization withDLAided Symmetric Human Activity Recognition(MWHODL-SHAR)model.The major intention of the MWHODL-SHAR model lies in recognition of symmetric activities,namely jogging,walking,standing,sitting,etc.In the presented MWHODL-SHAR technique,the human activities data is pre-processed in various stages to make it compatible for further processing.A convolution neural network with an attention-based long short-term memory(CNNALSTM)model is applied for activity recognition.The MWHO algorithm is utilized as a hyperparameter tuning strategy to improve the detection rate of the CNN-ALSTM algorithm.The experimental validation of the MWHODL-SHAR technique is simulated using a benchmark dataset.An extensive comparison study revealed the betterment of theMWHODL-SHAR technique over other recent approaches. 展开更多
关键词 Human activity recognition SYMMETRY deep learning machine learning pattern recognition time series classification
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Does light-intensity physical activity moderate the relationship between sitting time and adiposity markers in adolescents? 被引量:1
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作者 Ana María Contardo Ayala Jo Salmon +2 位作者 David W.Dunstan Lauren Arundell Anna Timperio 《Journal of Sport and Health Science》 SCIE 2022年第5期613-619,共7页
Background:While the relationship between sedentary time and adiposity markers may be independent of moderate-to-vigorous intensity physical activity(MVPA) among adolescents,little is known about the role of light-int... Background:While the relationship between sedentary time and adiposity markers may be independent of moderate-to-vigorous intensity physical activity(MVPA) among adolescents,little is known about the role of light-intensity physical activity(LIPA) in this relationship.The aim of this cross-sectional study was to examine whether device-measured LIPA and MVPA moderate the associations between objectively measured sitting time and adiposity markers(body mass index(BMI)) and waist circumference(WC)) among adolescents.Methods:This study included accelerometer and inclinometer data obtained from 219 adolescents(age=14.9±1.6 years,mean± SD),collected during 2014 and 2015 in Melbourne,Australia.ActiGraph GT3 X accelerometers were used to determine time spent in total-LIPA(101 counts/min to 3.99 metabolic equivalents(METs)) was dichotomized into low-LIPA(101-799 counts/min) and high LIPA(800 counts/min to 3.99 METs),and MVPA(> 4 METs).The average time spent sitting was obtained from activPAL inclinometers.Anthropometric measures were assessed by trained staff.Interactions between sitting and total-LIPA,low-LIPA,high-LIPA,and MVPA on BMI z-score(zBMI) and WC z-score(zWC),respectively,were examined using linear regression,adjusting for age and sex;and moderation by total-LIPA,low-LIPA,high-LIPA,and MVPA were examined by adding interaction terms.Significant interaction effects were probed by comparing associations at the mean and at 1 SD below and above the mean.Results:Total-LIPA significantly moderated the association between sitting time and zBMI,and low-LIPA significantly moderated the association between sitting time and zBMI and zWC.No other associations were found for total-LIPA,high-LIPA,or MVPA.Specifically,at high levels of total-LIPA(+1 SD),there is a negative association between sitting time and zBMI.In addition,at high levels of low-LIPA(+1 SD),there is a negative association between sitting time and zBMI and zWC.Conclusion:Associations between sitting and adiposity depended on time spent in total-LIPA and low-LIPA,but not high-LIPA or MVPA.Results suggest that increasing time spent in LIP A may provide protection from the deleterious effects of sitting on adiposity markers among adolescents.Experimental evidence is needed to support these conclusions. 展开更多
关键词 Adolescents Anthropometric measures OBESITY Physical activity Sedentary behavior Sitting time
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A Case-Control Study on Leisure Time Physical Activity (LTPA) during the Last Three Months of Pregnancy and Foetal Outcomes in Italy 被引量:1
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作者 Guglielmina Fantuzzi Elena Righi Gabriella Aggazzotti 《Health》 CAS 2016年第2期133-143,共11页
The association between Leisure Time Physical Activity (LTPA) during pregnancy and foetal outcomes has been extensively investigated. However, epidemiological studies specifically referred to LPTA in the last months o... The association between Leisure Time Physical Activity (LTPA) during pregnancy and foetal outcomes has been extensively investigated. However, epidemiological studies specifically referred to LPTA in the last months of pregnancy are scarce. We evaluated the association between LPTA and the risk of both preterm delivery and small for gestational age (SGA) during the last three months of pregnancy in Italy. A nationwide case-control study was performed in nine Italian cities. A total of 299 preterm delivery, 364 SGA and 855 controls were enrolled in the study. A self-administered questionnaire was used to assess socio-demographic variables, medical and reproductive history, life-style habits and LTPA referred to the last three months of pregnancy. Univariate and multivariate regression analyses were performed in order to estimate Odds ratios and 95% CI. LTPA during the last three months of pregnancy decreases the risk of preterm delivery (adjusted OR = 0.56;95% CI 0.39 - 0.79). Among the different types of physical activity, walking, the most frequently referred activity, appears significantly protective against preterm delivery (adjusted OR = 0.53;95% CI 0.36 - 0.81). Moreover, a small protective effect of walking was evidenced against SGA (adjusted OR = 0.72;95% CI 0.51 - 1.00). In conclusion, a mild physical activity such as walking in the last three months of pregnancy seems to reduce the risk of preterm delivery and, at a lesser extent, of SGA, confirming the beneficial effects of physical activity along the whole pregnancy. 展开更多
关键词 Leisure time Physical activity (LTPA) Preterm Delivery Small for Gestational Age Last Three Months of Pregnancy Case Control Study
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Fundamental motor skills,screen-time,and physical activity in preschoolers 被引量:15
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作者 E.Kipling Webster Corby K.Martin Amanda E.Staiano 《Journal of Sport and Health Science》 SCIE 2019年第2期114-121,共8页
Purpose: To examine the associations among preschoolers fundamental motor skills, screen-time, physical activity(PA), and sedentary behavior(SB).Methods: Children ages 3à4 years were enrolled in a prospective obs... Purpose: To examine the associations among preschoolers fundamental motor skills, screen-time, physical activity(PA), and sedentary behavior(SB).Methods: Children ages 3à4 years were enrolled in a prospective observational trial of PA. Trained assessors conducted the Test of Gross Motor Development-3 rd edition(TGMD-3), and the Movement Assessment Battery for Children-2 nd edition, and parent-reported child screen-time and sociodemographic information. Children wore an accelerometer for 7 days to examine SB and total PA(TPA). TPA was further characterized as moderateto-vigorous PA(MVPA) or vigorous PA(VPA). Mixed linear models were calculated, controlling for age(for TGMD-3), sex, household income, and accelerometer wear time(for accelerometry models), with childcare center as a random effect. The primary analysis reported on the cross-sectional baseline data of 126 children with complete fundamental motor skill and screen-time data; a subanalysis included 88 children with complete accelerometry data.Results: Children were 3.4 § 0.5 years of age(54% girls; 46% white, 42% African American, 12% other). A total of 48% lived in households at or below the federal poverty level. Children engaged in 5.1 § 3.6 h/day of screen-time. Children's screen-time was inversely related to the Movement Assessment Battery for Children-2 nd edition, manual dexterity skills percentile(b(SE) = ?1.7(0.8), p = 0.049). In the accelerometry subsample,children engaged in 5.9 § 0.9 h/day of TPA of which 1.7 § 0.6 h/day was MVPA. Boys engaged in more MVPA and VPA and less SB compared with girls(all p < 0.05). A higher TGMD-3, total score(b(SE) = 0.4(0.2), p = 0.017) and locomotor score(b(SE) = 0.7(0.3), p = 0.018) were associated with more VPA but not with TPA or MVPA. Screen-time and television in the bedroom were not related to SB, TPA, MVPA, or VPA.Conclusion: Children's motor skills were positively related to VPA but inversely related to screen-time. Further inquiry into the implications of high exposure to screen-time in young children is needed. 展开更多
关键词 FUNDAMENTAL motor SKILLS Physical activity PRESCHOOL Screen-time
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Time distribution characteristics of regional macroseismic activity in the Sichuan-Yunnan region and its significance to mid-long term prediction
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作者 黄玮琼 吴宣 《Acta Seismologica Sinica(English Edition)》 CSCD 2000年第4期368-374,共7页
The earthquakes with Ms≥6.0 are often gathered into belts or clusters and are roughly consistent with tectonic structure trends in the Sichuan-Yunnan (Chuan-Dian) region. The middle south part(98°-106°E, 21... The earthquakes with Ms≥6.0 are often gathered into belts or clusters and are roughly consistent with tectonic structure trends in the Sichuan-Yunnan (Chuan-Dian) region. The middle south part(98°-106°E, 21°-34°N) of South-North Seismic Zone can be zoned into seven small areas. There all were strong quakes with M_s≥7.0 historically in each small area. Ten earthquakes with M_s≥7.0 have occurred in this region since 1970 and they appeared in five small areas respectively. The relationships between occurrence-time and cumulative frequencies of strong quakes in these five areas are shown to be an exponential distribution or power function. By examining the inner coincidence it is indicated that these relationships are of definite significance to mid-long term macroseismic prediction of each area. 展开更多
关键词 macroseismic activity time distribution mid-long term prediction examination of inner coincidence
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FURTHER DISCUSSION ON STATISTICAL PROPERTIES OF ACTIVITY FLOW TIME IN PERT
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作者 Wang XinghuaDept.of Math.,Zhejiang Univ.,Hangzhou 310028. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2002年第1期1-6,共6页
In this paper attempts are made at answering the problems on the statistical properties of activity flow time in PERT raised by the late famous mathematician Hua Loo-keng.
关键词 PERT activity flow time the problem of Hua Loo-Keng.
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Discussion of the Horizontal Intensity of Late Quaternary Fault Activity Along the Tianjingshan Fault Zone in Different Time Intervals and Fault Segments 被引量:1
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作者 Chai Chizhang,Zhang Weiqi,and Jiao DechengSeismological Bureau of Ningxia Hui Autonomous Region,Yinchuan 750001,China 《Earthquake Research in China》 1997年第3期25-32,共8页
By computing and classifying the data of gully offset obtained from field surveys along the Tianjingshan fault zone and estimating the ages of three types of gullies,the strike-slip rates along the fault zone are disc... By computing and classifying the data of gully offset obtained from field surveys along the Tianjingshan fault zone and estimating the ages of three types of gullies,the strike-slip rates along the fault zone are discussed in different time intervals and fault segments.The results suggest that the intensity of activity along the fault zone is not strong,but the differences between different time intervals and fault segments since the late Pleistocene have been obvious.The average rates range from 0.23 mm/a to 1.62 mm/a.The largest average rate is 1.40 mm/a,which occurred in the early and middle of late Pleistocene along the western segment of the fault zone.Since the late stage of the late Pleistocene,the center of faulting activity of the fault zone has shifted to the middle segment,and the average slip rates range have changed from 1.30 mm/a to 1.63 mm/a. 展开更多
关键词 Discussion of the Horizontal Intensity of Late Quaternary Fault activity Along the Tianjingshan Fault Zone in Different time Intervals and Fault Segments activity
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Neighbourhood differences in objectively measured physical activity, sedentary time and body mass index
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作者 Stephanie A. Prince Mark S. Tremblay +3 位作者 Denis Prud’homme Rachel Colley Michael Sawada Elizabeth Kristjansson 《Open Journal of Preventive Medicine》 2011年第3期182-189,共8页
Background: There is limited Canadian research examining whether directly measured physical activity (PA) and body mass index (BMI) differ between neighbourhoods with different objectively measured socioeconomic (SES)... Background: There is limited Canadian research examining whether directly measured physical activity (PA) and body mass index (BMI) differ between neighbourhoods with different objectively measured socioeconomic (SES) and recreation (REC) environments. Purpose: To determine whether mean adult PA levels, sedentary time and BMIs were different across four neighbourhoods with contrasting SES and REC environments in Ottawa, Canada. Methods: This study employed a cross-sectional design to collect pilot data of objectively measured height, weight and PA (using accelerometry) and self-reported covariates in 113 adults (≥18 years). Four contrasting neighbourhoods (high REC/high SES, high REC/low SES, low REC/high SES, and low REC/low SES) were selected based on data collected as part of the Ottawa Neighbourhood Study. Analysis of covariance and logistic regression were used to perform neighbourhood comparisons for PA, sedentary time and BMI, adjusting for age, sex and household income and possible interactions. Post-hoc comparisons using Tukey’s test were performed. Results: Significant neighbourhood-group effects were observed for light intensity PA and sedentary time. Post-hoc tests identified that the low REC/high SES neighbourhood had significantly more minutes of light PA than the low REC/low SES (Mdiff = 56.05 minutes·day, Tukey p = 0.01). Unadjusted BMI differed between the four neighbourhoods, but the differences were not significant after controlling for age, sex and household income. Conclusions: This study demonstrates that light PA and sedentary time differ between neighbourhoods of varying REC and SES environments after controlling for differences in age, sex and household income. Findings also suggest that other area-level factors may explain these neighbourhood differences. 展开更多
关键词 PHYSICAL activity SEDENTARY time OBESITY Neighbourhood Environment
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Habitual physical activity levels and sedentary time of children in different childcare arrangements from a nationally representative sample of Canadian preschoolers
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作者 Julie Statler Piotr Wilk +2 位作者 Brian W.Timmons Rachel Colley Patricia Tucker 《Journal of Sport and Health Science》 SCIE 2020年第6期657-663,共7页
Background:Children spend substantial time in childcare,and the reasons parents choose a particular childcare type may differ by family.However,little is known about how childcare type influences habitual(full day)act... Background:Children spend substantial time in childcare,and the reasons parents choose a particular childcare type may differ by family.However,little is known about how childcare type influences habitual(full day)activity levels among children.Therefore,exploring patterns between childcare type and habitual physical activity(PA)(i.e.,light,moderate-to-vigorous PA(MVPA),and total PA)and sedentary time(ST)in young Canadian children is needed.Methods:A nationally representative sample of preschoolers from Cycles 3 and 4 of the Canadian Health Measures Survey was used in this cross-sectional study.Childcare type(e.g.,center-based childcare,home-based childcare,home with parent,kindergarten)was reported by parents.Preschoolers wore an Actical accelerometer for 7 days.Device and population-spcific cut-points were applied to delineate PA intensities and ST.Population means and sample totals were calculated to examine average daily and hourly rates of activity.Results:Preschoolers’rates of MVPA and total PA from the 4 childcare arrangements ranged from 65.99 min/day to 74.62 min/day(5.48-6.18 min/h)and 274.20 min/day to 281.66 min/day (22.69-23.21 min/h),respectively,while ST ranged from 443.13 min/day to 460.57 min/day(36.80-37.31 min/h).No significant differences were observed in daily or hourly rates of activity.Conclusion:This study provides a snapshot of the levels of PA and ST among preschoolers in various childcare settings at a national level,with no differences observed in habitual activity levels based on childcare enrollment.Additional research is needed to clarify the relationship between young children’s PA and childcare type,with consideration given to the quality of the childcare settings. 展开更多
关键词 Early learning environment Motor activity PRESCHOOL Screen time
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Effect of Plant Ash on Nutrient Quality and Antioxidant Activity of African Yam Bean Seed Porridge in Relation to Cooking Time
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作者 Anthony N. Ukom Faith C. Egejuru +1 位作者 Philippa C. Ojimelukwe Ugwuona U. Fabian 《Food and Nutrition Sciences》 2020年第7期591-602,共12页
The present study aimed to investigate the nutrient quality, antioxidant activity and sensory acceptability of hard-to-cook African yam bean (AYB) seeds cooked for 5</span><span style="font-family:"... The present study aimed to investigate the nutrient quality, antioxidant activity and sensory acceptability of hard-to-cook African yam bean (AYB) seeds cooked for 5</span><span style="font-family:""> </span><span style="font-family:Verdana;">h (control) and for 2 h with plant ash. The plant ash were unripe plantain peel ash (UPA), corn cob ash (CCA) and UPA and CCA mixture. Standard methods of Association of Official Analytical Chemists (AOAC) w</span><span style="font-family:Verdana;">ere</span><span style="font-family:""><span style="font-family:Verdana;"> used for the proximate and mineral analysis, DPPH, ABTS and FRAP assays were used to investigate the antioxidant activity. A completely randomized design with one way analysis of variance (ANOVA) was used for data </span><span style="font-family:Verdana;">analysis. The results showed that cooking of AYB seeds for 2 h with 8</span></span><span style="font-family:""> </span><span style="font-family:Verdana;">g/100mL</span><span style="font-family:Verdana;"> plant ash solution improved the nutrient contents, antioxidant activity and sensory scores of the porridge. Higher values of proteins, ash and energy were obtained in 8</span><span style="font-family:""> </span><span style="font-family:Verdana;">g/100mL UPA/CCA and in 8</span><span style="font-family:""> </span><span style="font-family:Verdana;">g/100mL CCA additives. However, moisture, fat and fibre contents were not affected by plant ash additives and were higher in 5 h cooked porridge. Cooking with 8</span><span style="font-family:""> </span><span style="font-family:Verdana;">g/100mL plant ash solution for 2 h significantly increased mineral elements in the porridge. Phenolic compounds (total polyphenols and flavonoids), and antioxidant activity (DPPH, ABTS and FRAP) showed higher values with plant ash additives. This study reveals that addition of plant ash did not only reduce the cooking time of AYB seed by 60%, but also improved the nutrient quality, antioxidant activity and sensory acceptability. 展开更多
关键词 African Yam Bean Plant Ash Porridge Cooking time Nutrient Quality Antioxidant activity Sensory Acceptability
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