Objectively measured physical activity and sedentary time in European adolescents: the HELENA study

The authors' aim in this cross-sectional study was to characterize levels of objectively measured physical activity and sedentary time in adolescents from 9 European countries. The study comprised 2,200 European adolescents (1,184 girls) participating in the HELENA cross-sectional study (2006-2008). Physical activity was measured by accelerometry and was expressed as average intensity (counts/minute) and amount of time (minutes/day) spent engaging in moderate- to vigorous-intensity physical activity (MVPA). Time spent in sedentary behaviors was also objectively measured. Cardiorespiratory fitness was measured by means of the 20-m shuttle run test. Level of maternal education was reported by the adolescents. A higher proportion of boys (56.8% of boys vs. 27.5% of girls) met the physical activity recommendations of at least 60 minutes/day of MVPA. Adolescents spent most of the registered time in sedentary behaviors (9 hours/day, or 71% of the registered time). Both average intensity and MVPA were higher in adolescents with high cardiorespiratory fitness, and sedentary time was lower in the high-fitness group. There were no physical activity or sedentary time differences between maternal education categories. These data provide an objective measure of physical activity and amount of time spent in sedentary behaviors in a relatively large number of European adolescents.     

Objectively measured sedentary time and associations with insulin sensitivity: Importance of reallocating sedentary time to physical activity

ObjectiveThe aim of this study is to quantify associations between objectively measured sedentary time and markers of insulin sensitivity by considering allocation into light-intensity physical activity or moderate- to vigorous-intensity physical activity (MVPA).MethodsParticipants with an increased risk of impaired glucose regulation (IGR) were recruited (Leicestershire, United Kingdom, 2010–2011). Sedentary, light-intensity physical activity and MVPA time were measured using accelerometers. Fasting and 2-hour post-challenge insulin and glucose were assessed; insulin sensitivity was calculated by HOMA-IS and Matsuda-ISI. Isotemporal substitution regression models were used. Data were analysed in 2014.Results508 participants were included (average age = 65 years, female = 34%). Reallocating 30 min of sedentary time into light-intensity physical activity was associated a 5% (95% CI 1, 9%; p = 0.024) difference in Matsuda-ISI after adjustment for measured confounding variables. Reallocation into MVPA was associated with a 15% (7, 25%; p < 0.001) difference in HOMA-IS and 18% (8, 28%; p < 0.001) difference in Matsuda-ISI. Results for light-intensity physical activity were modified by IGR status with stronger associations seen in those with IGR.ConclusionsReallocating sedentary time into light-intensity physical activity or MVPA was associated with differences in insulin sensitivity, with stronger and more consistent associations seen for MVPA.     

Obesity, physical activity and sedentary behavior amongst British and Saudi youth: a cross-cultural study

This study explores differences in weight status, obesity and patterns of physical activity (PA) in relation to gender and age of youth from two culturally, environmentally and geographically diverse countries, the United Kingdom (UK) and Saudi Arabia (SA). A total of 2,290 males and females (15-17 years) volunteered to participate in this study. Participants completed a validated self-report questionnaire that contained 47 items relating to patterns of PA, sedentary activity and eating habits. The questionnaire allows the calculation of total energy expenditure in metabolic equivalent (MET-min) values per week. Significant differences in percentage of overweight/obese and levels of PA were evident between the youth from the two countries, with males being generally more physically active than females. Additionally, there were significant associations between Body Mass Index (BMI), PA and sedentary behaviors; the youth with higher BMI reported lower levels of PA and higher amounts of sedentary time. These findings highlight the diverse nature of lifestyle of youth living in different geographical areas of the world and the need for further research to explore the socio-cultural factors that impact on the prevalence of obesity and patterns of PA of youth in different populations.     

Objectively measured intensity of physical activity and adiposity in middle-aged women

OBJECTIVE: The aim of this study was to evaluate the relationship between objectively measured physical activity (ACT), particularly intensity of physical activity (iACT), and body fat percentage (BF%) in 278 middle-aged women. Secondary purposes were to ascertain the association between physical activity duration (dACT) and BF% and the extent to which potentially confounding factors, including total ACT, energy intake, body weight, and season of assessment, influenced the relationship between iACT and BF%. RESEARCH METHODS AND PROCEDURES: A cross-sectional design was used. Subjects were apparently healthy, 35 to 45 years old, premenopausal, nonsmokers, with BMIs < 30 kg/m2. Approximately 90 percent were white, 81% were married, and 37% were college graduates. ACT was assessed using Computer Science and Application accelerometers worn for 7 consecutive days. The accelerometers recorded movement continuously, and activity counts were collapsed into 10-minute epochs. Intensity was indexed using seven activity count cut-off points, and duration was based on the number of 10-minute epochs at each intensity level. BF% was assessed using multiple measurements in the Bod Pod. Energy intake was measured using 7-day weighed diet records during the same week subjects wore the accelerometers. RESULTS: BF% was strongly and inversely associated with iACT and dACT. Controlling for energy intake and body weight strengthened the relationships among iACT, dACT, and BF%. Control of total ACT weakened the association. DISCUSSION: Engaging in higher intensity and/or longer duration ACT is associated with lower BF% compared with lower intensity and/or shorter durations of activity.     

Objectively measured habitual physical activity in a highly obesogenic environment

Background   While the prevalence of overweight and obesity among children continues to grow nationally, prevalence in the North-East of England is among the highest in the UK. The objective of this study was to investigate the habitual physical activity levels in a particularly obesogenic environment in the North-East of England.
Methods   Eight primary schools were selected using a stratified random sampling frame ranking average deprivation levels. Participating children ( n  = 246, mean age 10 years) wore an accelerometer (Actigraph, GT-256) over five consecutive days (weekend plus three weekdays). Total daily moderate-to-vigorous intensity physical activity was calculated using thresholds by Puyau and colleagues.
Results   Only 7% (17/246) of children were sufficiently active. Boys were more physically active than girls (766 ± 268 vs. 641 ± 202 counts/min, 95% CI for the difference 63–186 cpm.). Total physical activity was not influenced significantly by deprivation levels or weight status, and there were no significant differences in physical activity between school or weekend days.
Conclusions   The North-East of England is a recognized 'hot spot' for paediatric obesity and the present study shows that low levels of habitual physical activity are typical. Choice of accelerometry threshold affects both the apparent amount of physical activity and the ability to detect groups with particularly low levels of physical activity.     

Objectively measured physical activity, physical activity related personality and body mass index in 6- to 10-yr-old children: a cross-sectional study

Background  

The prevalence and level of overweight in childhood is rapidly increasing. One potential contributor to the rise in overweight is a decline in physical activity (PA). The purpose of this study was to compare levels and patterns of PA and PA related personality in normal-weight (NW) and overweight (OW) 6- to 10-yr-old children.     

Objectively measured physical activity of USA adults by sex, age, and racial/ethnic groups: a cross-sectional study

Background  

Accelerometers were incorporated in the 2003–2004 National Health and Nutritional Examination Survey (NHANES) study cycle for objective assessment of physical activity. This is the first time that objective physical activity data are available on a nationally representative sample of U.S. residents. The use of accelerometers allows researchers to measure total physical activity, including light intensity and unstructured activities, which may be a better predictor of health outcomes than structured activity alone. The aim of this study was to examine objectively determined physical activity levels by sex, age and racial/ethnic groups in a national sample of U.S. adults.     

Replacing sedentary time with physical activity: effects on health-related quality of life in older Japanese adults

Background

The isotemporal substitution (IS) approach can be used to assess the effect of replacing one activity with the equal duration of another activity on relevant outcomes. This study examined the associations of objectively assessed sedentary behavior (SB) and physical activity (PA) with health-related quality of life (HRQOL) in older Japanese adults, using the IS approach.

Methods

Participants were 287 older Japanese adults (aged 65–84?years) who wore accelerometers for at least 7 days. We calculated the average daily time spent in SB (≤1.5 METs); light-intensity PA (LPA: >?1.5 to <?3.0 METs); and moderate- to vigorous-intensity PA (MVPA: ≥3.0 METs) per day. HRQOL was assessed using the Medical Outcomes Survey Short Form-8 questionnaire.

Results

The IS models showed replacing SB or LPA with MVPA to be significantly associated with better physical component summary scores. Replacing SB with MVPA was marginally associated with better mental component summary scores.

Conclusion

These findings indicate that replacing SB with the same amount of MVPA may contribute to better physical HRQOL in older adults.

     

Objectively measured access to recreational destinations and leisure-time physical activity: Associations and demographic moderators in a six-country study

Within the growing body of research linking neighbourhood environmental attributes with physical activity, associations between recreational destinations and non-walking leisure-time physical activity (LTPA) are rarely studied, and to date, not across multiple cities. We examined six potential associations of objectively-measured access to private recreational facilities (e.g., fitness centres, swimming pools) and parks with adults’ non-walking LTPA (e.g., swimming, cycling, tennis), using data gathered with consistent methods from adults living in international cities with a range of environment attributes. The potential effects of socio-demographic moderators and between-city variations were also examined. Data from 6725 adults from 10 cities (6 countries) were gathered. Adults were more likely to engage in non-walking LTPA if they had a greater number of private recreational facilities within 0.5 or 1 km of the home, particularly in women, and if they lived closer to a park. The amount of non-zero LTPA was only associated (positively) with the number of recreational facilities within 1 km. Relationships between amount of LTPA and park proximity appear complex, with likely contextual and cultural differences. Improving access to private recreational facilities could promote non-walking LTPA, especially in women.     

浅谈健步走的价值意义与科学方法

目的研究健走干预前后职业人群慢性病危险因素的变化情况,探索适合上海市职业人群的健走运动干预模式。方法选取1 475名机关、企事业单位员工进行为期100 d的健走干预,比较干预前后体重、BMI、腰围、体脂肪率和内脏脂肪指数,以及超重和肥胖率、中心性肥胖率、血压控制率的变化情况。结果通过100 d的干预,干预人群的体重减轻(1.52±2.75)kg(Z=-21.99,P＜0.01),BMI降低(0.55±1.03)kg/m²(Z=-21.64,P＜0.01),腰围缩小(2.10±5.27)cm(Z=-17.62,P＜0.01),体脂肪率降低(0.31±4.59)%(Z=-3.48,P＜0.01),内脏脂肪指数降低(0.12±1.99)(Z=-2.70,P＜0.01),收缩压和舒张压分别降低(2.51±10.87)mmHg (Z=-9.35,P＜0.01)和(1.67±8.26)mmHg (Z=-9.06,P＜0.01)。超重及肥胖率下降了7.86%,中心性肥胖率下降了6.92%,血压控制率上升了2.72%,干预前后比较差异均有统计学意义(χ²=916.48,P＜0.01;χ²=585.90,P＜0.01;χ²=366.37,P＜0.01)。结论职业人群通过健走运动干预可以降低人群中超重和肥胖率、中心性肥胖率,提高血压控制率,慢性病相关危险因素得到明显改善,对慢性病预防控制起到积极作用。     

久坐时间及体力活动与儿童超重肥胖的联合关系研究

目的 探明久坐时间(ST)、体力活动(PA)与儿童超重肥胖的联合关系,为从身体活动角度制定儿童超重肥胖的防控策略提供依据。方法 本研究采用分层整群随机抽样方法,于2017年3-6月共抽取3 936名广州市7~12岁儿童。采用信效度良好的问卷评估儿童的ST和PA水平,儿童超重肥胖依据中国肥胖工作组制定的标准进行判定。每天进行课后ST≥2 h/d视为高ST,每天参加中高等强度PA≥60 min/d视为高PA;高、低ST和PA两两交叉分组后形成四组别。结果 广州市7~12岁儿童总体的超重肥胖率为21.5%。低ST高PA、低ST低PA、高ST高PA、高ST低PA四组别儿童的超重肥胖率分别为18.9%,17.8%,23.1%和22.3%。在控制了混杂因素后,与低ST高PA组儿童相比较,高ST高PA组儿童的超重肥胖风险是其1.286倍(95%CI:1.078~1.724),高ST低PA组儿童的超重肥胖风险是其1.219倍(95%CI:1.059~1.641)。结论 ST、PA与儿童超重肥胖间存在联合关系,有关部门从身体活动角度防控儿童超重肥胖时,除了考虑增加儿童中高等强度PA水平,也应多关注减少课后ST。     

Associations between physical activity,sedentary time and social-emotional functioning in young children

BackgroundThis study preliminarily examined the relationship between physical activity, sedentary time, and social emotional functioning in children aged 4–6 years.MethodsEighty children attending kindergarden classes in Ottawa, Canada wore Actical accelerometers for 1-week to directly assess their physical activity and sedentary time. Physical activity was quantified as minutes per day in light intensity or moderate intensity, and steps per day, while sedentary time was quantified as minutes per day. Social emotional functioning attributes were assessed by teachers using the Devereux Students Strengths Assessment.ResultsAfter controlling for age, sex, household-income and school clustering using multilevel regression models, steps per day were positively associated with social awareness β = 1.537, CI = 0.115–2.959) self-awareness (β = 1.285, CI = 0.014–2.555), relationship skills (β = 1.729, CI = 0.238–3.219), personal responsibilities (β = 1.689, CI = 0.101–3.276), and optimistic thinking (β = 1.091, CI = 0.251–2.157). Moderate physical activity was positively associated with relationship skills (β = 1.598, CI = 0.065–3.131) and optimistic thinking (β = 1.515, CI = 0.069–2.234). Time spent in light physical activity and sedentary time were not associated with social emotional functioning indicators.ConclusionsPhysical activity as measured by steps per day and time spent in moderate physical activity was associated with better social emotional functioning. Future research is needed to verify these preliminary findings and determine the directionality of relationships observed, and experimental studies are needed to determine whether promoting either increased steps per day or intensity of physical activity can improve social emotional functioning in the early years.     

Objectively measured physical activity,cardiorespiratory fitness and cardiometabolic risk factors in the Health Survey for England

Objectives

The study aims to test the hypothesis that physical activity (PA) and cardiorespiratory fitness (CRF) are associated with cardiometabolic risk factors; and to test the hypothesis that CRF modifies (changes the direction and/or strength of) the associations between PA and cardiometabolic risk factors.

Methods

PA and CRF were objectively measured in the 2008 Health Survey for England and the present study included 536 adults who completed at least 4 min of the eight-minute sub-maximal step test and wore an accelerometer for at least 10 h on at least four days. Linear regression models were fitted to examine the relationship between PA and cardiometabolic risk factors and between CRF and cardiometabolic risk factors. A test of interaction was performed to examine whether CRF modifies the associations between PA and cardiometabolic risk factors.

Results

PA and CRF were associated with HDL cholesterol, the ratio of total to HDL cholesterol, glycated haemoglobin and BMI after adjustment for potential confounders. There was little evidence that CRF changed the direction or strength of associations between PA and cardiometabolic risk factors.

Conclusions

PA and CRF are associated with cardiometabolic risk factors. A larger sample is required to determine if CRF modifies associations between PA and cardiometabolic risk factors.     

Atherosclerosis and physical functioning in older men, a longitudinal study

Objective

Functional decline is a major threat to independency, progressing into functional limitations and eventually leading to disability. Chronic diseases, especially cardiovascular diseases, are important determinants of functional limitations and disability. Vascular damage exits long before it is clinically manifest and can have adverse effects on health, physical and cognitive functioning. The objective was to investigate the association between non-invasive atherosclerosis measures and physical functioning in older men.

Design

Prospective cohort study.

Setting

The study was conducted in the general community.

Participants

195 independently living older men.

Measurements

Atherosclerosis was measured by intima media thickness (CIMT) of the common carotid artery using ultrasonography and assessment for presence of atherosclerotic plaques. Physical functioning was measured by isometric handgrip strength and leg extensor strength using a hand held dynamometer, lower extremity function using the physical performance score and ability to perform activities of daily life using the modified Stanford Health Assessment Questionnaire. Linear regression analysis was performed to estimate the associations between CIMT or plaques and physical functioning.

Results

After adjustment for confounders, higher baseline CIMT was associated with lower isometric handgrip strength at follow up (β^CIMT =?7.21, 95% CI[?13.64;?0.77]). No other associations were found between CIMT and physical functioning. In addition, no associations were found for the presence of plaques and physical functioning either at baseline, or at follow-up.

Conclusion

Atherosclerosis, as measured by higher CIMT, is related to a lower isometric handgrip strength at follow-up, but no further associations with physical functioning were found in this longitudinal study among independently living older men.     

Objectively assessed physical activity,fitness and subjective wellbeing

BackgroundThe existing evidence for a cross-sectional association between physical activity and subjective wellbeing is inconsistent, mainly because of the reliance on self reported physical activity, which might have conceptual overlap with subjective health.PurposeTo examine associations of objectively assessed physical activity and cardiorespiratory fitness with subjective wellbeing.MethodsA sub-sample of participants (921 men and women, mean age 44.6 ± 15.0 yrs, 46.4% men) from the 2008 Health Survey for England completed objective measures of physical activity (Actigraph) and an 8 min sub-maximal step test to estimate levels of cardiorespiratory fitness. The General Health Questionnaire and self-rated health was used as indicators of subjective wellbeing.ResultsThe recorded levels of moderate to vigorous physical activity (MVPA) were higher in participants reporting very good health (adjusted mean difference = 6.7, 95% CI, 1.1–12.4 min/d, p = 0.019) compared with participants reporting fair–poor health after adjustment for various confounders and fitness level. Neither physical fitness, objectively assessed sedentary time or light activity was related to self-rated health. There was also no association between objectively measured physical activity and fitness with psychological health, despite a robust association with self reported MVPA in the overall sample.ConclusionsObjectively assessed MVPA is independently associated with self-rated health. Self reported, but not objectively assessed MVPA, was associated with psychological health. The null findings with regards to psychological health might partly reflect selection biases associated with the healthy nature of this sub-sample of participants.