Sedentary time and its association with risk for disease incidence, mortality, and hospitalization in adults: a systematic review and meta-analysis

Morning breathing exercises prolong lifespan by improving hyperventilation in people living with respiratory cancer

Disturbance of oxygen-carbon dioxide homeostasis has an impact on cancer. Little is known about the effect of breath training on cancer patients. Here we report our 10-year experience with morning breathing exercises (MBE) in peer-support programs for cancer survivors.We performed a cohort study to investigate long-term surviving patients with lung cancer (LC) and nasopharyngeal cancer (NPC) who practiced MBE on a daily basis. End-tidal breath holding time (ETBHT) after MBE was measured to reflect improvement in alveolar O2 pressure and alveolar CO2 pressure capacity.Patients (female, 57) with a diagnosis of LC (90 patients) and NPC (32 patients) were included. Seventy-six of them were MBE trainees. Average survival years were higher in MBE trainees (9.8 ± 9.5) than nontrainees (3.3 ± 2.8). The 5-year survival rate was 56.6% for MBE trainees and 19.6% for nontrainees (RR = 5.371, 95% CI = 2.271-12.636, P < 0.001). Survival probability of the trainees further increased 17.9-fold for the 10-year survival rate. Compared with the nontrainees, the MBE trainees shows no significant differences in ETBHT (baseline, P = 0.795; 1-2 years, P = 0.301; 3-4 years, P = 0.059) at baseline and within the first 4 years. From the 5th year onwards, significant improvements were observed in ETBHT, aCO2%, PaCO2, and PaO2 (P = 0.028). In total, 18 trainees (40.9%) and 20 nontrainees (74.1%) developed new metastasis (RR = 0.315, 95% CI = 0.108-0.919, P = 0.031).MBE might benefit for the long-term survival in patients with LC and NPC due to improvement in hyperventilation.

Physical activity as a vital sign in patients with bipolar disorder

The most significant contributor to premature mortality in patients with bipolar disorder is preventable cardiovascular diseases. This study investigated if the Physical Activity Vital Sign (PAVS) assessment (two questions which clarify if a person meets the recommended 150min of physical activity per week) can identify patients with bipolar disorder at higher risk of cardio-metabolic abnormalities. Clinical differences between those who adhere and those who did not adhere to the physical activity guidelines were investigated using an ANCOVA controlling for age and gender. Sixty-five (29♂) in- and outpatients with bipolar disorder (age=45.1±9.8years) completed the PAVS-questions, underwent full-fasting metabolic screening, and performed a six-minute walk test (6MWT). Those patients not meeting the physical activity recommendations had a higher body mass index, performed worse on the 6MWT and were at a significantly higher risk for cardio-metabolic diseases. Relative risks ranged from 1.33 for having dyslipidemia to 5.33 for hyperglycemia. The current data offer the first evidence that the PAVS assessment might be a useful vital sign in the routine assessment of in- and outpatients with bipolar disorder.

The prevalence, awareness and control rate of hypertension among elderly in northwest of Iran

Introduction: Adequate treatment of hypertension is infrequent in older patients. Determining the prevalence of hypertension in older patients, identifying the pattern of the treatment in this age group and evaluating their awareness of the disease may help healthcare systems to devise appropriate programs for controlling the disease.

Methods: This descriptive cross sectional study included a sample from population of Tabriz, a large city in North-West of Iran, who were 60 years or older. Data collection and blood pressure measurements were conducted in the households of the participants from 1st June 2015 through 1st August 2015. Hypertension was defined as systolic and/or diastolic blood pressure (DBP) ≥150/90 mm Hg or receiving anti-hypertensive medications. Prevalence and determinants of hypertension, awareness of patients about their diagnosis and prevalence of treatment and adequately controlled blood pressure were determined.

Results: The prevalence of hypertension was 68.0%. Among hypertensive patients 81.8% were aware of their diagnosis, 78.0% were receiving antihypertensive medications. Among treated patients, 46.2% were adequately controlled. In univariate analysis, prevalence of hypertension was significantly higher in women (74.0% vs. 60.7%, P < 0.001). Women were more likely to be aware of diagnosis and to receive antihypertensive medications; however, the prevalence of adequately controlled blood pressure was similar in treated men and women. Among included variables in logistic regression analysis, older age, lower number of family members in household, cardiac diseases, being on low salt low fat diet, higher Body mass index (BMI) and not being educated were independently associated with having hypertension.

Conclusion: Hypertension is highly prevalent among older population of Tabriz. Despite high rate of treatment, the rates of control are relatively low, indicating a demand for prevention and better management of hypertension in older individuals.

Association of Maximum Temperature With Sedentary Time in Older British Men

Background

Sedentary behavior is very common in older adults and a risk factor for mortality. Understanding determinants of sedentary behavior may help in defining strategies aimed to reduce the time spent sedentary. The degree of difference in sedentary time attributable to varying temperatures has not been yet estimated in older men.

Methods

Men aged 71 to 91 years participating in an established UK population-based cohort study were invited to wear an Actigraph GT3X accelerometer for 1 week in 2010–12. Outcome was sedentary time (<1.5 Metabolic Equivalent of Task) in minutes per day. Associations between daily outdoor maximum temperature and accelerometer-measured sedentary time were estimated using multilevel models.

Results

43% (1361/3137) of invited men participated in the study and provided adequate data. Men spent on average 615 minutes in sedentary time per day (72% of the total accelerometer-wear time). After adjusting for covariates, men spent 26 minutes more per day (P < .001) in sedentary time when temperatures were in the lowest (–3.5; 9.2°C) versus highest quintile (19.1; 29.5°C).

Conclusions

Sedentary time in older adults is highest at lowest temperatures, typically recorded in winter. Findings are relevant for guidelines: interventions may consider targeting older men in winter providing recommendations for minimizing sedentariness on daily basis.

Sedentary behaviours among adults across Canada

OBJECTIVES: While cross-Canada variations in physical activity and weight status have been illustrated, less is known about sedentary behaviour (SB). The aim of this study was to describe various SBs and their correlates among Canadian adults. METHODS: Cross-sectional data from the 2011-2012 Canadian Community Health Survey included 92,918 respondents aged 20-75+ years, representative of >22 million Canadian adults. TV/video viewing, computer, video game playing and reading time were self-reported. Associations with socio-demographic, health and health behaviour variables were examined. RESULTS: About 31% of adults reported >2 hours/day TV viewing, while 47% of men and 41% of women reported >5 hours/week computer use, 24% of men and 12% of women reported ≥1 hour/week video game playing, and 33% of men and 46% of women reported >5 hours/week reading; 28% of respondents reported ≥5 hours/day total SB time. Age was the strongest correlate: adults 75+ had 5 and 6 times greater odds respectively of reporting >2 hours/day TV viewing and >5 hours/week reading, but far lesser odds of reporting high computer or video game time, compared to adults 20-24. Other variables associated with specific SBs included gender, marital status, education, occupation, income and immigrant status, as well as BMI, weight perceptions, smoking, diet and physical activity. CONCLUSION: Common sedentary behaviours were associated with numerous socio-demographic, health and health behaviour characteristics in a large representative sample of Canadians. These correlates differed according to the type of SB. Public health interventions targeting SB should be behavior-specific and tailored to the population segment of interest.

High Amounts of Sitting, Low Cardiorespiratory Fitness, and Low Physical Activity Levels: 3 Key Ingredients in the Recipe for Influencing Metabolic Syndrome Prevalence

Purpose:

Limited research has evaluated the independent and additive associations of moderate-to-vigorous physical activity (MVPA), sedentary behavior (SB), and cardiorespiratory fitness (CRF) with metabolic syndrome, which was the purpose of this study.

Design:

Cross-sectional.

Setting:

National Health and Nutrition Examination Survey 2003 to 2004.

Sample:

Three hundred seven adults aged 20 to 49 years.

Measures:

Moderate-to-vigorous physical activity and SB were assessed via accelerometer, whereas CRF was assessed via submaximal treadmill testing. Metabolic syndrome was assessed via the American Heart Association/National Heart, Lung, and Blood Institute guidelines.

Analysis:

Multivariable logistic regression.

Results:

A 10 min/d increase in MVPA was associated with a 45% reduced odds of metabolic syndrome (odds ratio [OR] = 0.55, 95% confidence interval [CI] = 0.40-0.76, P = .001), and a 10 mL/kg/min increase in CRF was associated with a 43% reduced odds of having metabolic syndrome (OR = 0.57, 95% CI = 0.37-0.87, P = .013). Additionally, a statistically significant combined association of MVPA, SB, and CRF with metabolic syndrome was present; individuals who had below-median SB and above-median MVPA and CRF had an 88% reduced odds of metabolic syndrome (OR = 0.12, 95% CI = 0.03-0.48, P = .005) when compared to those who had below-median MVPA and CRF and above-median SB.

Conclusion:

When considering MVPA, SB, and CRF, MVPA and CRF were both independently associated with metabolic syndrome (SB was not) among this young adult population and there was also evidence to support a combined association of all 3 parameters on metabolic syndrome.

Sedentary behavior, physical activity and cardiorespiratory fitness on leukocyte telomere length

Background: Emerging work is starting to investigate the cumulative effects of moderate-to-vigorous physical activity (MVPA), sedentary behavior and cardiorespiratory fitness on health. The objective of this study was to examine the cumulative and independent associations of MVPA, sedentary behavior and cardiorespiratory fitness on leukocyte telomere length (LTL).

Methods: Data from the 1999-2002 National Health and Nutrition Examination Survey (NHANES) were used (N = 1868 adults 20+ years); analyzed in 2016. Sedentary behavior and MVPA were subjectively assessed with cardiorespiratory fitness determined from a submaximal treadmill-based test; participants were classified as above or below the median values for each of these three parameters. A blood sample was obtained from each participant to assess LTL via quantitative polymerase chain reaction, with participants grouped into LTL tertiles.

Results: Participants who engaged in higher MVPA, sat less and had higher cardiorespiratory fitness had an increased odds (ranging from 85% to 105%) of being in LTL tertile 3 (vs. 1). In an extended adjusted multinomial logistic regression model, only MVPA was positively associated with LTL (odds ration [OR] = 1.37; 95% CI: 0.99-1.90; P = 0.05).

Conclusion: All three behavior characteristics, but particularly MVPA, may be important in preserving LTLs.

Using Sit-to-Stand Workstations in Offices: Is There a Compensation Effect?

PURPOSE

Sit-to-stand workstations are becoming common in modern offices and are increasingly being implemented in sedentary behavior interventions. The purpose of this study was to examine whether the introduction of such a workstation among office workers leads to reductions in sitting during working hours, and whether office workers compensate for any reduction in sitting at work by increasing sedentary time and decreasing physical activity (PA) outside work.

METHODS

Office workers (n = 40; 55% female) were given a WorkFit-S, sit-to-stand workstation for 3 months. Participants completed assessments at baseline (before workstation installation), 1 wk and 6 wk after the introduction of the workstation, and again at 3 months (postintervention). Posture and PA were assessed using the activPAL inclinometer and ActiGraph GT3X+ accelerometer, which participants wore for 7 d during each measurement phase.

RESULTS

Compared with baseline, the proportion of time spent sitting significantly decreased (75% ± 13% vs 52% ± 16% to 56% ± 13%), and time spent standing and in light activity significantly increased (standing: 19% ± 12% vs 32% ± 12% to 37% ± 15%, light PA: 14% ± 4% vs 16% ± 5%) during working hours at all follow-up assessments. However, compared with baseline, the proportion of time spent sitting significantly increased (60% ± 11% vs 66% ± 12% to 68% ± 12%) and light activity significantly decreased (21% ± 5% vs 19% ± 5%) during nonworking hours across the follow-up measurements. No differences were seen in moderate-to-vigorous activity during nonworking hours throughout the study.

CONCLUSION

The findings suggest that introducing a sit-to-stand workstation can significantly reduce sedentary time and increase light activity levels during working hours. However, these changes were compensated for by reducing activity and increasing sitting outside of working hours. An intervention of a sit-to-stand workstation should be accompanied by an intervention outside of working hours to limit behavior compensation.

Office workers' objectively assessed total and prolonged sitting time: Individual-level correlates and worksite variations

Sedentary behavior is highly prevalent in office-based workplaces; however, few studies have assessed the attributes associated with this health risk factor in the workplace setting. This study aimed to identify the correlates of office workers' objectively-assessed total and prolonged (≥ 30 min bouts) workplace sitting time. Participants were 231 Australian office workers recruited from 14 sites of a single government employer in 2012-13. Potential socio-demographic, work-related, health-related and cognitive-social correlates were measured through a self-administered survey and anthropometric measurements. Associations with total and prolonged workplace sitting time (measured with the activPAL3) were tested using linear mixed models. Worksites varied significantly in total workplace sitting time (overall mean [SD]: 79% [10%] of work hours) and prolonged workplace sitting time (42% [19%]), after adjusting for socio-demographic and work-related characteristics. Organisational tenure of 3-5 years (compared to tenure > 5 years) was associated with more time spent in total and prolonged workplace sitting time, while having a BMI categorised as obese (compared to a healthy BMI) was associated with less time spent in total and prolonged workplace sitting time. Significant variations in sitting time were observed across different worksites of the same employer and the variation remained after adjusting for individual-level factors. Only BMI and organisational tenure were identified as correlates of total and prolonged workplace sitting time. Additional studies are needed to confirm the present findings across diverse organisations and occupations.

Evaluation of raw acceleration sedentary thresholds in children and adults

The aim was to develop sedentary (sitting/lying) thresholds from hip and wrist worn raw tri-axial acceleration data from the ActiGraph and GENEActiv, and to examine the agreement between free-living time spent below these thresholds with sedentary time estimated by the activPAL. Sixty children and adults wore an ActiGraph and GENEActiv on the hip and wrist while performing six structured activities, before wearing the monitors, in addition to an activPAL, for 24 h. Receiver operating characteristic (ROC) curves were used to determine sedentary thresholds based on activities in the laboratory. Agreement between developed sedentary thresholds during free-living and activPAL were assessed by Bland-Altman plots and by calculating sensitivity and specificity. Using laboratory data and ROC-curves showed similar classification accuracy for wrist and hip thresholds (Area under the curve = 0.84-0.92). Greatest sensitivity (97-98%) and specificity (74-78%) were observed for the wrist thresholds, with no large differences between brands. During free-living, Bland-Altman plots showed large mean individual biases and 95% limits of agreement compared with activPAL, with smallest difference for the ActiGraph wrist threshold in children (+30 min, P = 0.3). Sensitivity and specificity for the developed thresholds during free-living were low for both age groups and for wrist (Sensitivity, 68-88%, Specificity, 46-59%) and hip placements (Sensitivity, 89-97%, Specificity, 26-34%). Laboratory derived sedentary thresholds generally overestimate free-living sedentary time compared with activPAL. Wrist thresholds appear to perform better than hip thresholds for estimating free-living sedentary time in children and adults relative to activPAL, however, specificity for all the developed thresholds are low.

Objectively measured sedentary behavior and moderate-to-vigorous physical activity on the health-related quality of life in US adults: The National Health and Nutrition Examination Survey 2003-2006

BACKGROUND

Health-related quality of life (HRQOL) represents an individual's perception of physical, mental, and social well-being and is a strong predictor of health status. Few studies have examined associations of sedentary behavior (SB) and moderate-to-vigorous physical activity (MVPA) with HRQOL in the general population.

PURPOSE

This study aimed to determine combined associations of objectively measured SB and MVPA on the risk of poor HRQOL in the general US population, after controlling for potential confounding factors.

METHODS

We analyzed data from 5359 adults from the National Health and Nutrition Examination Survey 2003-2006. HRQOL was measured using a HRQOL-4 consisting of four questions focused on the self-perception of general health, physical health, mental health, and activity limitation. We dichotomized each HRQOL-4 component as good versus poor and defined poor overall HRQOL when participants had any poor HRQOL components. SB and MVPA were measured using an accelerometer. Survey logistic models were examined to estimate the odds ratio (OR) and 95% confidence interval (CI) for poor HRQOL by SB and MVPA as tertiles.

RESULTS

When examined as a combination of SB and MVPA, a substantial decrease in the risk of poor overall HRQOL was found in individuals with low SB/high MVPA [OR 0.69 (95% CI 0.51-0.94) and moderate SB/high MVPA (OR 0.56 (95% CI 0.40-0.78)], but no significant decrease was found in individuals with high SB/high MVPA (vs. high SB/low MVPA).

CONCLUSION

Our findings suggest that both increasing MVPA and reducing time spent in SB may be useful strategies to improve HRQOL.

Accelerometer-measured dose-response for physical activity, sedentary time, and mortality in US adults

BACKGROUND

Moderate-to-vigorous-intensity physical activity is recommended to maintain and improve health, but the mortality benefits of light activity and risk for sedentary time remain uncertain.

OBJECTIVES

Using accelerometer-based measures, we 1) described the mortality dose-response for sedentary time and light- and moderate-to-vigorous-intensity activity using restricted cubic splines, and 2) estimated the mortality benefits associated with replacing sedentary time with physical activity, accounting for total activity.

DESIGN

US adults (n = 4840) from NHANES (2003-2006) wore an accelerometer for ≤7 d and were followed prospectively for mortality. Proportional hazards models were used to estimate adjusted HRs and 95% CIs for mortality associations with time spent sedentary and in light- and moderate-to-vigorous-intensity physical activity. Splines were used to graphically present behavior-mortality relation. Isotemporal models estimated replacement associations for sedentary time, and separate models were fit for low- (<5.8 h total activity/d) and high-active participants to account for nonlinear associations.

RESULTS

Over a mean of 6.6 y, 700 deaths occurred. Compared with less-sedentary adults (6 sedentary h/d), those who spent 10 sedentary h/d had 29% greater risk (HR: 1.29; 95% CI: 1.1, 1.5). Compared with those who did less light activity (3 h/d), those who did 5 h of light activity/d had 23% lower risk (HR: 0.77; 95% CI: 0.6, 1.0). There was no association with mortality for sedentary time or light or moderate-to-vigorous activity in highly active adults. In less-active adults, replacing 1 h of sedentary time with either light- or moderate-to-vigorous-intensity activity was associated with 18% and 42% lower mortality, respectively.

CONCLUSIONS

Health promotion efforts for physical activity have mostly focused on moderate-to-vigorous activity. However, our findings derived from accelerometer-based measurements suggest that increasing light-intensity activity and reducing sedentary time are also important, particularly for inactive adults.

Sitting Less and Moving More: Improved Glycaemic Control for Type 2 Diabetes Prevention and Management

Epidemiological evidence indicates that excessive time spent in sedentary behaviours (too much sitting) is associated with an increased risk of type 2 diabetes (T2D). Here, we highlight findings of experimental studies corroborating and extending the epidemiological evidence and showing the potential benefits for T2D of reducing and breaking up sitting time across the whole day. We also discuss future research opportunities and consider emerging implications for T2D prevention and management. This new evidence is stimulating an expansion of diabetes-related physical activity guidelines-suggesting that in addition to moderate-vigorous physical activity, reducing and regularly interrupting prolonged sitting time is likely to have important and varied benefits across the spectrum of diabetes risk.

Associations of Accelerometry-Assessed and Self-Reported Physical Activity and Sedentary Behavior With All-Cause and Cardiovascular Mortality Among US Adults

The US physical activity (PA) recommendations were based primarily on studies in which self-reported data were used. Studies that include accelerometer-assessed PA and sedentary behavior can contribute to these recommendations. In the present study, we explored the associations of PA and sedentary behavior with all-cause and cardiovascular disease (CVD) mortality in a nationally representative sample. Among the 2003-2006 National Health and Nutrition Examination Survey cohort, 3,809 adults 40 years of age or older wore an accelerometer for 1 week and self-reported their PA levels. Mortality data were verified through 2011, with an average of 6.7 years of follow-up. We used Cox proportional hazards models to obtain adjusted hazard ratios and 95% confidence intervals. After excluding the first 2 years, there were 337 deaths (32% or 107 of which were attributable to CVD). Having higher accelerometer-assessed average counts per minute was associated with lower all-cause mortality risk: When compared with the first quartile, the adjusted hazard ratio was 0.37 (95% confidence interval: 0.23, 0.59) for the fourth quartile, 0.39 (95% confidence interval: 0.27, 0.57) for the third quartile, and 0.60 (95% confidence interval: 0.45, 0.80) second quartile. Results were similar for CVD mortality. Lower all-cause and CVD mortality risks were also generally observed for persons with higher accelerometer-assessed moderate and moderate-to-vigorous PA levels and for self-reported moderate-to-vigorous leisure, household and total activities, as well as for meeting PA recommendations. Accelerometer-assessed sedentary behavior was generally not associated with all-cause or CVD mortality in fully adjusted models. These findings support the national PA recommendations to reduce mortality.

Living well after breast cancer randomized controlled trial protocol: evaluating a telephone-delivered weight loss intervention versus usual care in women following treatment for breast cancer

BACKGROUND

Obesity, physical inactivity and poor diet quality have been associated with increased risk of breast cancer-specific and all-cause mortality as well as treatment-related side-effects in breast cancer survivors. Weight loss intervention trials in breast cancer survivors have shown that weight loss is safe and achievable; however, few studies have examined the benefits of such interventions on a broad range of outcomes and few have examined factors important to translation (e.g. feasible delivery method for scaling up, assessment of sustained changes, cost-effectiveness). The Living Well after Breast Cancer randomized controlled trial aims to evaluate a 12-month telephone-delivered weight loss intervention (versus usual care) on weight change and a range of secondary outcomes including cost-effectiveness.

METHODS/DESIGN

Women (18-75 years; body mass index 25-45 kg/m2) diagnosed with stage I-III breast cancer in the previous 2 years are recruited from public and private hospitals and through the state-based cancer registry (target n = 156). Following baseline assessment, participants are randomized 1:1 to either a 12-month telephone-delivered weight loss intervention (targeting diet and physical activity) or usual care. Data are collected at baseline, 6-months (mid-intervention), 12-months (end-of-intervention) and 18-months (maintenance). The primary outcome is change in weight at 12-months. Secondary outcomes are changes in body composition, bone mineral density, cardio-metabolic and cancer-related biomarkers, metabolic health and chronic disease risk, physical function, patient-reported outcomes (quality of life, fatigue, menopausal symptoms, body image, fear of cancer recurrence) and behaviors (dietary intake, physical activity, sitting time). Data collected at 18-months will be used to assess whether outcomes achieved at end-of-intervention are sustained six months after intervention completion. Cost-effectiveness will be assessed, as will mediators and moderators of intervention effects.

DISCUSSION

This trial will provide evidence needed to inform the wide-scale provision of weight loss, physical activity and dietary interventions as part of routine survivorship care for breast cancer survivors.

TRIAL REGISTRATION

Australian and New Zealand Clinical Trial Registry (ANZCTR) - ACTRN12612000997853 (Registered 18 September 2012).

Physical activity in primary and secondary prevention of cardiovascular disease: Overview updated

Although the observed progress in the cardiovascular disease treatment, the incidence of new and recurrent coronary artery disease remains elevated and constitutes the leading cause of death in the developed countries. Three-quarters of deaths due to cardiovascular diseases could be prevented with adequate changes in lifestyle, including increased daily physical activity. New evidence confirms that there is an inverse dose-response relationship between physical activity and cardiovascular disease and mortality risk. However, participation in moderate to vigorous physical activity may not fully attenuate the independent effect of sedentary activities on increased risk for cardiovascular diseases. Physical activity also plays an important role in secondary prevention of cardiovascular diseases by reducing the impact of the disease, slowing its progress and preventing recurrence. Nonetheless, most of eligible cardiovascular patients still do not benefit from secondary prevention/cardiac rehabilitation programs. The present review draws attention to the importance of physical activity in the primary and secondary prevention of cardiovascular diseases. It also addresses the mechanisms by which physical activity and regular exercise can improve cardiovascular health and reduce the burden of the disease.

Factors Associated with Sedentary Behavior in Patients with Intermittent Claudication

OBJECTIVES

Time spent in sedentary behavior has been associated with cardio-metabolic risk factors in the general population and in patients with symptomatic peripheral artery disease (PAD). Given the association of sedentary behavior and poor health outcomes, it is important to identify factors associated with sedentary behavior in these patients. The aim of this study was to identify factors associated with the sedentary time in patients with symptomatic PAD.

METHODS

The sample included 297 patients with symptomatic PAD. Sedentary behavior was assessed using a step activity monitor and the patients were divided into tertiles. Demographic data, body mass index, comorbid conditions, and measures of severity of PAD (ankle brachial index, ischemic window, claudication measurements, peak oxygen uptake and walking economy) were obtained.

RESULTS

Patients in the highest tertile (i.e. more sedentary) had a higher body mass index and a higher prevalence of diabetes mellitus, metabolic syndrome, and obesity than patients in the lowest tertile, whereas their peak walking time, peak oxygen uptake, and walking economy were lower (p < .05 for all). Using multiple regression procedures, the factors associated with the sedentary time were male sex (b = .217, R² = .180, p = .001), body mass index (b = .154, R² = .059, p = .013), peak walking time (b = -.360, R² = .066, p ≤ .001), and walking economy (b = -.187, R² = .142, p = .004).

CONCLUSION

In patients with symptomatic PAD, greater time spent in sedentary behavior was found in men, and in patients with higher body mass index, lower peak walking time, and lower walking economy.

Metabolic Profiling of Total Physical Activity and Sedentary Behavior in Community-Dwelling Men

Objective

Physical activity is known to be preventive against various non-communicable diseases. We investigated the relationship between daily physical activity level and plasma metabolites using a targeted metabolomics approach in a population-based study.

Methods

A total of 1,193 participants (male, aged 35 to 74 years) with fasting blood samples were selected from the baseline survey of a cohort study. Information on daily total physical activity, classified into four levels by quartile of metabolic equivalent scores, and sedentary behavior, defined as hours of sitting per day, was collected through a self-administered questionnaire. Plasma metabolite concentrations were quantified by capillary electrophoresis mass spectrometry method. We performed linear regression analysis models with multivariable adjustment and corrected p-values for multiple testing in the original population (n = 808). The robustness of the results was confirmed by replication analysis in a separate population (n = 385) created by random allocation.

Results

Higher levels of total physical activity were associated with various metabolite concentrations, including lower concentrations of amino acids and their derivatives, and higher concentrations of pipecolate (FDR p <0.05 in original population). The findings persisted after adjustment for age, body mass index, smoking, alcohol intake, and energy intake. Isoleucine, leucine, valine, 4-methyl-2-oxoisopentanoate, 2-oxoisopentanoate, alanine, and proline concentrations were lower with a shorter sitting time.

Conclusions

Physical activity is related to various plasma metabolites, including known biomarkers for future insulin resistance or type 2 diabetes. These metabolites might potentially play a key role in the protective effects of higher physical activity and/or less sedentary behavior on non-communicable diseases.

Physical Environmental Correlates of Domain-Specific Sedentary Behaviours across Five European Regions (the SPOTLIGHT Project)

Background

The relation between neighbourhood environmental factors and domain-specific sedentary behaviours among adults remains unclear. This study firstly aims to examine the association of perceived and objectively measured neighbourhood safety, aesthetics, destinations and functionality with transport-related, work-related and leisure-time sedentary behaviour. Secondly, the study aims to assess whether these associations are moderated by age, gender or educational level.

Methods

In 60 randomly sampled neighbourhoods from 5 urban regions in Europe (Ghent and suburbs, Paris and inner suburbs, Budapest and suburbs, the Randstad, and Greater London), a virtual audit with Google Street View was performed to assess environmental characteristics. A total of 5,205 adult inhabitants of these neighbourhoods reported socio-demographic characteristics, sedentary behaviours, and neighbourhood perceptions in an online survey. Generalized linear mixed models were conducted to examine associations between physical environmental neighbourhood factors and sedentary behaviours. Interaction terms were added to test the moderating role of individual-level socio-demographic variables.

Results

Lower levels of leisure-time sedentary behaviour (i.e. all leisure activities except television viewing and computer use) were observed among adults who perceived greater numbers of destinations such as supermarkets, recreational facilities, or restaurants in their neighbourhood, and among adults who lived in a neighbourhood with more objectively measured aesthetic features, such as trees, water areas or public parks. Lower levels of work-related sedentary behaviour were observed among adults who perceived less aesthetic features in their neighbourhood, and among adults who lived in a neighbourhood with less objectively measured destinations. Both age, gender and educational level moderated the associations between neighbourhood environmental factors and sedentary behaviours.

Conclusion

Preliminary evidence was found for associations between neighbourhood environmental factors and domain-specific sedentary behaviours among adults. However, these associations varied according to objective or subjective environmental measures. More research is needed to confirm and clarify the associations.

The Impact of Wearable Device Enabled Health Initiative on Physical Activity and Sleep

Objectives

The Personal Health Management Study (PHMS) is an assessment of the effect of a voluntary employee-facing health initiative using a commercially-available wearable device implemented among 565 employees of Boehringer Ingelheim Pharmaceuticals, Inc. The results of the initiative on physical activity (measured as steps) and sleep is reported.

Methods

This was a 12-month, prospective, single-cohort intervention study using a wearable activity-measuring device tracking steps and sleep (entire study period) and a system of health-promoting incentives (first nine months of study period). The findings from the first nine study months are reported.

Results

The mixed model repeated measures approach was used to analyze the data. There was no significant difference in steps between the first month (7915.6 mean steps per person per day) and the last month (7853.4 mean steps per person per day) of the intervention. However, there was a seasonal decline in steps during the intervention period from fall to winter, followed by an increase in steps from winter to spring. In contrast, sleep tended to increase steadily throughout the study period, and the number of hours slept during the last month (7.52 mean hours per person per day) of the intervention was significantly greater than the number of hours slept during the first month (7.16 mean hours per person per day).

Conclusions

The impact of the initiative on physical activity and sleep differed over the period of time studied. While physical activity did not change between the first and last month of the intervention, the number of hours slept per night increased significantly. Although seasonal changes and study-device habituation may explain the pattern of change in physical activity, further evaluation is required to clarify the reasons underlying the difference in the impact of the initiative on the dynamics of steps and sleep.

Intensity Thresholds on Raw Acceleration Data: Euclidean Norm Minus One (ENMO) and Mean Amplitude Deviation (MAD) Approaches

Objectives

(1) To develop and internally-validate Euclidean Norm Minus One (ENMO) and Mean Amplitude Deviation (MAD) thresholds for separating sedentary behaviours from common light-intensity physical activities using raw acceleration data collected from both hip- and wrist-worn tri-axial accelerometers; and (2) to compare and evaluate the performances between the ENMO and MAD metrics.

Methods

Thirty-three adults [mean age (standard deviation (SD)) = 27.4 (5.9) years; mean BMI (SD) = 23.9 (3.7) kg/m²; 20 females (60.6%)] wore four accelerometers; an ActiGraph GT3X+ and a GENEActiv on the right hip; and an ActiGraph GT3X+ and a GENEActiv on the non-dominant wrist. Under laboratory-conditions, participants performed 16 different activities (11 sedentary behaviours and 5 light-intensity physical activities) for 5 minutes each. ENMO and MAD were computed from the raw acceleration data, and logistic regression and receiver-operating-characteristic (ROC) analyses were implemented to derive thresholds for activity discrimination. Areas under ROC curves (AUROC) were calculated to summarise performances and thresholds were assessed via executing leave-one-out-cross-validations.

Results

For both hip and wrist monitor placements, in comparison to the ActiGraph GT3X+ monitors, the ENMO and MAD values derived from the GENEActiv devices were observed to be slightly higher, particularly for the lower-intensity activities. Monitor-specific hip and wrist ENMO and MAD thresholds showed excellent ability for separating sedentary behaviours from motion-based light-intensity physical activities (in general, AUROCs >0.95), with validation indicating robustness. However, poor classification was experienced when attempting to isolate standing still from sedentary behaviours (in general, AUROCs <0.65). The ENMO and MAD metrics tended to perform similarly across activities and accelerometer brands.

Conclusions

Researchers can utilise these robust monitor-specific hip and wrist ENMO and MAD thresholds, in order to accurately separate sedentary behaviours from common motion-based light-intensity physical activities. However, caution should be taken if isolating sedentary behaviours from standing is of particular interest.

Physical activity and anomalous bodily experiences in patients with first-episode schizophrenia

BACKGROUND

Low physical activity is strongly correlated with metabolic syndrome (MetS) and poor physical health. Although the prevalence of MetS is high in patients with first-episode schizophrenia (FES), little is still known about the level of and possible barriers for physical activity in FES.

AIM

The purpose of the study was to compare physical activity in patients with FES with healthy controls; to investigate changes in physical activity over 1 year of follow-up; and to explore the correlations of physical activity and anomalous bodily experiences reported by patients with FES.

METHODS

Both physical activity and aerobic fitness were measured. Anomalous bodily experiences were measured by selected items from the Examination of Anomalous Self-Experience and The Body Awareness Scale. Psychopathological data comprising negative and positive symptoms and data on psychotropic medication were obtained from medical records of all patients.

RESULTS

Physical activity and aerobic fitness was significantly lower in patients with FES compared with healthy controls (p < 0.001). Over 1 year of follow-up patients had lower physical activity and aerobic fitness. Patients with more severe anomalous bodily experiences had significantly lower physical activity compared with patients with fewer such experiences (p = 0.030). In linear regression analyses only negative symptoms were significantly correlated with low physical activity (β = -0.88; 95% confidence interval = -1.48 to -0.29; p < 0.001).

CONCLUSION

Physical activity and aerobic fitness is low in patients with FES. Both anomalous bodily experiences and negative symptoms are significantly correlated with low physical activity.

Objectively measured physical activity and plasma metabolomics in the Shanghai Physical Activity Study

BACKGROUND

Physical activity is associated with a variety of health benefits, but the biological mechanisms that explain these associations remain unclear. Metabolomics is a powerful tool to comprehensively evaluate global metabolic signature associated with physical activity and helps to pinpoint the pathways that mediate the health effects of physical activity. There has been limited research on metabolomics and habitual physical activity, and no metabolomics study has examined sedentary behaviour and physical activity of different intensities.

METHODS

In a group of Chinese adults (N = 277), we used an untargeted approach to examine 328 plasma metabolites in relation to accelerometer-measured physical activity, including overall volume of physical activity (physical activity energy expenditure (PAEE) and duration of physically active time) and sedentary time, and measures related to different intensities of physical activity (moderate-to-vigorous activity (MVPA), light activity, average physical activity intensity).

RESULTS

We identified 11 metabolites that were associated with total activity, with a false discovery rate of 0.2 or lower. Notably, we observed generally lower levels of amino acids in the valine, leucine and isoleucine metabolism pathway and of carbohydrates in sugar metabolism among participants with higher activity levels. Moreover, we found that PAEE, time spent in light activity and duration of physically active time were associated with a similar metabolic pattern, whereas the metabolic signature associated with sedentary time mirrored this pattern. In contrast, average activity intensity and time spent in MVPA appeared to be associated with somewhat different metabolic patterns.

CONCLUSIONS

Overall, the metabolomics patterns support a beneficial role of higher volume of physical activity in cardiometabolic health. Our findings identified candidate pathways and provide insight into the mechanisms underlying the health effects of physical activity.

Sedentary behavior and residual-specific mortality

Background: The purpose of this study was to examine the association of accelerometer-assessed sedentary behavior and residual-specific mortality. Methods: Data from the 2003-2006 National Health and Nutrition Examination Survey (NHANES) were used (N = 5536), with follow-up through 2011. Sedentary behavior was objectively measured over 7 days via accelerometry. Results: When expressing sedentary behavior as a 60 min/day increase, the hazard ratio across the models ranged from 1.07-1.40 (P < 0.05). There was evidence of an interaction effect between sedentary behavior and total physical activity on residual-specific mortality (Hazard ratiointeraction [HR] = 0.9989; 95% CI: 0.9982-0.9997; P = 0.008). Conclusion: Sedentary behavior was independently associated with residual-specific mortality. However, there was evidence to suggest that residual-specific mortality risk was a function of sedentary behavior and total physical activity. These findings highlight the need for future work to not only examine the association between sedentary behavior and health independent of total physical activity, but evaluate whether there is a joint effect of these two parameters on health.

Sitting time and obesity in a sample of adults from Europe and the USA

BACKGROUND

Obesity is a risk factor for many chronic diseases and the prevalence is increasing worldwide. Research suggests that sedentary behaviour (sitting) may be related to obesity.

AIM

To examine the association between sitting time and obesity, while controlling for physical activity, in a large international sample.

SUBJECTS AND METHODS

In total, 5338 adults from the UK, USA, Germany, Spain, Italy, France, Portugal, Austria and Switzerland self-reported their total daily sitting time, physical activity, age, height and weight. BMI (kg/m²), total physical activity (MET-minutes/week) and sitting time (hours/day) were derived. Participants were grouped into quartiles based on their daily sitting time (<4, 4-≤6, 6-≤8 and >8 hours/day) and logistic regression models explored the odds of being obese vs normal weight for each sitting time quartile.

RESULTS

Participants in the highest sitting time quartile (≥8 hours/day) had 62% higher odds of obesity compared to participants in the lowest quartile (<4 hours/day) after adjustment for physical activity and other confounding variables (OR = 1.62, 95% CI = 1.24-2.12, p < .01).

CONCLUSION

Sitting time is associated with obesity in adults, independent of physical activity. Future research should clarify this association using objective measures of sitting time and physical activity to further inform health guidelines.

Does physical activity attenuate, or even eliminate, the detrimental association of sitting time with mortality? A harmonised meta-analysis of data from more than 1 million men and women

BACKGROUND

High amounts of sedentary behaviour have been associated with increased risks of several chronic conditions and mortality. However, it is unclear whether physical activity attenuates or even eliminates the detrimental effects of prolonged sitting. We examined the associations of sedentary behaviour and physical activity with all-cause mortality.

METHODS

We did a systematic review, searching six databases (PubMed, PsycINFO, Embase, Web of Science, Sport Discus, and Scopus) from database inception until October, 2015, for prospective cohort studies that had individual level exposure and outcome data, provided data on both daily sitting or TV-viewing time and physical activity, and reported effect estimates for all-cause mortality, cardiovascular disease mortality, or breast, colon, and colorectal cancer mortality. We included data from 16 studies, of which 14 were identified through a systematic review and two were additional unpublished studies where pertinent data were available. All study data were analysed according to a harmonised protocol, which categorised reported daily sitting time and TV-viewing time into four standardised groups each, and physical activity into quartiles (in metabolic equivalent of task [MET]-hours per week). We then combined data across all studies to analyse the association of daily sitting time and physical activity with all-cause mortality, and estimated summary hazard ratios using Cox regression. We repeated these analyses using TV-viewing time instead of daily sitting time.

FINDINGS

Of the 16 studies included in the meta-analysis, 13 studies provided data on sitting time and all-cause mortality. These studies included 1 005 791 individuals who were followed up for 2-18·1 years, during which 84 609 (8·4%) died. Compared with the referent group (ie, those sitting <4 h/day and in the most active quartile [>35·5 MET-h per week]), mortality rates during follow-up were 12-59% higher in the two lowest quartiles of physical activity (from HR=1·12, 95% CI 1·08-1·16, for the second lowest quartile of physical activity [<16 MET-h per week] and sitting <4 h/day; to HR=1·59, 1·52-1·66, for the lowest quartile of physical activity [<2·5 MET-h per week] and sitting >8 h/day). Daily sitting time was not associated with increased all-cause mortality in those in the most active quartile of physical activity. Compared with the referent (<4 h of sitting per day and highest quartile of physical activity [>35·5 MET-h per week]), there was no increased risk of mortality during follow-up in those who sat for more than 8 h/day but who also reported >35·5 MET-h per week of activity (HR=1·04; 95% CI 0·99-1·10). By contrast, those who sat the least (<4 h/day) and were in the lowest activity quartile (<2·5 MET-h per week) had a significantly increased risk of dying during follow-up (HR=1·27, 95% CI 1·22-1·31). Six studies had data on TV-viewing time (N=465 450; 43 740 deaths). Watching TV for 3 h or more per day was associated with increased mortality regardless of physical activity, except in the most active quartile, where mortality was significantly increased only in people who watched TV for 5 h/day or more (HR=1·16, 1·05-1·28).

INTERPRETATION

High levels of moderate intensity physical activity (ie, about 60-75 min per day) seem to eliminate the increased risk of death associated with high sitting time. However, this high activity level attenuates, but does not eliminate the increased risk associated with high TV-viewing time. These results provide further evidence on the benefits of physical activity, particularly in societies where increasing numbers of people have to sit for long hours for work and may also inform future public health recommendations.

FUNDING

None.

Identifying adults' valid waking wear time by automated estimation in activPAL data collected with a 24 h wear protocol

The activPAL monitor, often worn 24 h d^-1, provides accurate classification of sitting/reclining posture. Without validated automated methods, diaries-burdensome to participants and researchers-are commonly used to ensure measures of sedentary behaviour exclude sleep and monitor non-wear. We developed, for use with 24 h wear protocols in adults, an automated approach to classify activity bouts recorded in activPAL 'Events' files as 'sleep'/non-wear (or not) and on a valid day (or not). The approach excludes long periods without posture change/movement, adjacent low-active periods, and days with minimal movement and wear based on a simple algorithm. The algorithm was developed in one population (STAND study; overweight/obese adults 18-40 years) then evaluated in AusDiab 2011/12 participants (n  =  741, 44% men, aged  >35 years, mean  ±  SD 58.5  ±  10.4 years) who wore the activPAL3^™ (7 d, 24 h d^-1 protocol). Algorithm agreement with a monitor-corrected diary method (usual practice) was tested in terms of the classification of each second as waking wear (Kappa; κ) and the average daily waking wear time, on valid days. The algorithm showed 'almost perfect' agreement (κ  >  0.8) for 88% of participants, with a median kappa of 0.94. Agreement varied significantly (p  <  0.05, two-tailed) by age (worsens with age) but not by gender. On average, estimated wear time was approximately 0.5 h d^-1 higher than by the diary method, with 95% limits of agreement of approximately this amount  ±2 h d^-1. In free-living data from Australian adults, a simple algorithm developed in a different population showed 'almost perfect' agreement with the diary method for most individuals (88%). For several purposes (e.g. with wear standardisation), adopting a low burden, automated approach would be expected to have little impact on data quality. The accuracy for total waking wear time was less and algorithm thresholds may require adjustments for older populations.

Moderate to vigorous physical activity, not sedentary time, is associated with total and regional adiposity in a sample of UK adults at risk of type 2 diabetes

How sedentary time (ST) relates to total and regional adiposity and whether these associations are independent of moderate- to vigorous-intensity physical activity (MVPA) are of clinical and public health interest. We assessed the relationship between objectively measured MVPA, ST and ST breaks in adults at risk of type 2 diabetes. The sample consisted of 163 adults (37-75 years) recruited from primary care. Dual energy x-ray absorptiometry (iDXA, GE Corp) was used to estimate total and regional (appendages and trunk) fat mass as well as fat mass in the abdominal (android) and hip/thigh (gynoid) regions. The Actigraph GT3X was worn for 7 days (participants with  ⩾4 valid days included herein) and published cut-points were applied to 15 s epoch data to estimate mean MVPA, ST and breaks in ST. Multiple regression investigated associations between both ST and MVPA with total and regional adiposity without and with adjustment for known and potential confounders (including total lean mass) and for each other. MVPA was negatively and significantly associated with total (b  =  -62; p  =  0.002), and regional (p  <  0.05) adiposity before and after adjusting for confounders including ST. Although ST was positively and significantly associated with total (b  =  46.4; p  =  0.002) and regional adiposity (all p  ⩽  0.007), these relationships disappeared after adjustment for MVPA (p  >  0.05). Sedentary breaks were not significantly related to adiposity before or after adjustment. An age-by-MVPA interaction for total, android, gynoid and trunk fat revealed that MVPA did not remain significant when controlling for ST and other covariates in the adults over 65 years old. In this sample of adults at risk of type 2 diabetes, MVPA, and not ST, was associated with total and regional adiposity after adjustment for each other. However, in older adults at risk of T2D weight related benefits may be gained from reducing daily ST and increasing MVPA.

Novel technology to help understand the context of physical activity and sedentary behaviour

When used in large, national surveillance programmes, objective measurement tools provide prevalence estimates of low physical activity guideline compliance and high amounts of sedentary time. There are undoubtedly a plethora of reasons for this but one possible contributing factor is the current lack of behavioural context offered by accelerometers and posture sensors. Context includes information such as where the behaviour occurs, the type of activity being performed and is vital in allowing greater refinement of intervention strategies. Novel technologies are emerging with the potential to provide this information. Example data from three ongoing studies is used to illustrate the utility of these technologies. Study one assesses the concurrent validity of electrical energy monitoring and wearable cameras as measures of television viewing. This study found that on average the television is switched on for 202 min d^-1 but is visible in just 90 min of wearable camera images with a further 52 min where the participant is in their living room but the television is not visible in the image. Study two utilises indoor location monitoring to assess where older adult care home residents accumulate their sedentary time. This study found that residents were highly sedentary (sitting for an average of 720 min d^-1) and spent the majority of their time in their own rooms with more time spent in communal areas in the morning than in the afternoon. Lastly, study three discusses the use of proximity sensors to quantify exposure to a height adjustable desk. These studies are example applications of this technology, with many other technologies available and applications possible. The adoption of these technologies will provide researchers with a more complete understanding of the behaviour than has previously been available.

Associations of sitting time and occupation with metabolic syndrome in South Korean adults: a cross-sectional study

BACKGROUND

Previous evidence suggests that there is a correlation between prolonged sitting time and cardio-metabolic disease, such as metabolic syndrome (MS). Cardiovascular disease is the second-leading cause of mortality in South Korea, a country with the longest working hours among all member states of the Organization for Economic Co-operation and Development. However, no previous study has investigated the relationships of overall sitting-time and occupation with MS in South Korea. Accordingly, the present study examined these relationships in a South Korean population.

METHODS

Data from the sixth Korean National Health and Nutrition Examination Survey (KNHANES), a nationally representative survey with a cross-sectional design, were used in the present study. MS diagnoses were evaluated using the International Diabetes Foundation (IDF) criteria. Participants self-reported their overall sitting times, and occupations were classified using the Korean version of the Standard Classification of Occupations (KSCO). A multiple logistic regression analysis was conducted to evaluate the associations of sitting time and occupation with MS.

RESULTS

The risk of MS was 1.21-fold higher among participants who sat for >7 h/day than among those who sat for ≤7 h/day (odds ratio [OR]: 1.21, 95 % confidence interval [CI]: 1.00-1.46). Regarding occupation, office workers had a two-fold higher risk of MS than did agriculture, forestry, and fishery (AFF) workers (OR: 2.01, 95 % CI: 1.26-3.22). In a combined analysis of sitting time and occupation, male participants who sat for >7 h/day and reported an occupation that involves office work (OW) or machine fitting (MF) were significantly more likely to have MS when compared to those who sat for ≤7 h/day and were employed as AFF workers (>7 h/day × OW, OR: 2.41, 95 % CI: 1.05-5.51; >7 h/day × MF, OR: 2.92, 95 % CI: 1.43-5.93).

CONCLUSIONS

Excessive sitting time and a sedentary occupation correlated positively with MS in South Korean adults. Accordingly, a reduction in the overall sitting time or inclusion of energy-expending activities in the workplace might improve the rate of MS.

Do Running and Strength Exercises Reduce Daily Muscle Inactivity Time?

Understanding how a specific exercise changes daily activity patterns is important when designing physical activity interventions. We examined the effects of strength and interval running exercise sessions on daily activity patterns using recordings of quadriceps and hamstring muscle electromyographic (EMG) activity and inactivity. Five male and five female subjects taking part in a 10-week training programme containing both strength and interval running training sessions were measured for daily muscle EMG activities during three days: on a strength day, an interval running day, and a day without exercise. EMG was measured using textile electrodes embedded into sport shorts that were worn 9.1 ± 1.4 hours/day and results are given as % of recording time. During the total measurement time the muscles were inactive 55 ± 26%, 53 ± 30% and 71 ± 12% during strength training day, interval running day, and day without exercise (n.s.). When compared to the day without exercise, the change in muscle inactivity correlated negatively with change in light muscle activity in strength (r = -0.971, p < 0.001) and interval running days (r = -0.965, p < 0.001). While interval running exercise bout induced a more systematic decrease in muscle inactivity time (from 62 ± 15% to 6 ± 6%, p < 0.001), reductions in muscle inactivity in response to strength exercise were highly individual (range 5–70 pp) despite the same training programme. Strength, but not running exercise bout, increased muscle activity levels occurring above 50% MVC (p < 0.05) when compared to a similar period without exercise. The effect of strength exercise bout on total daily recording time increased the EMG amplitudes across the entire intensity spectrum. While strength and interval running exercise are effective in increasing muscle moderate-to-vigorous activity when compared to a similar period without exercise, it comprises only a small part of the day and does not seem to have a systematic effect neither to reduce nor induce compensatory increase in the daily muscle inactivity that is highly heterogeneous between individuals.

Feasibility and acceptability of reducing workplace sitting time: a qualitative study with Australian office workers

Background

Office workers spend a large proportion of their working hours sitting. This may contribute to an increased risk of chronic disease and premature mortality. While there is growing interest in workplace interventions targeting prolonged sitting, few qualitative studies have explored workers’ perceptions of reducing occupational sitting outside of an intervention context. This study explored barriers to reducing office workplace sitting, and the feasibility and acceptability of strategies targeting prolonged sitting in this context.

Methods

Semi-structured interviews were conducted with a convenience sample of 20 office workers (50 % women), including employees and managers, in Melbourne, Australia. The three organisations (two large, and one small organisation) were from retail, health and IT industries and had not implemented any formalised approaches to sitting reduction. Questions covered barriers to reducing sitting, the feasibility of potential strategies aimed at reducing sitting, and perceived effects on productivity. Interviews were audiotaped and transcribed verbatim. Data were analysed using thematic analysis.

Results

Participants reported spending most (median: 7.2 h) of their working hours sitting. The nature of computer-based work and exposure to furniture designed for a seated posture were considered to be the main factors influencing sitting time. Low cost strategies, such as standing meetings and in-person communication, were identified as feasible ways to reduce sitting time and were also perceived to have potential productivity benefits. However, social norms around appropriate workplace behaviour and workload pressures were perceived to be barriers to uptake of these strategies. The cost implications of height-adjustable workstations influenced perceptions of feasibility. Managers noted the need for an evidence-based business case supporting action on prolonged sitting, particularly in the context of limited resources and competing workplace health priorities.

Conclusions

While a number of low-cost approaches to reduce workplace sitting are perceived to be feasible and acceptable in the office workplace, factors such as work demands and the organisational social context may still act as barriers to greater uptake. Building a supportive organisational culture and raising awareness of the adverse health effects of prolonged sitting may be important for improving individual-level and organisational-level motivation for change.

All-cause mortality risk as a function of sedentary behavior, moderate-to-vigorous physical activity and cardiorespiratory fitness

OBJECTIVE

Emerging work demonstrates individual associations of sedentary behavior, moderate-to-vigorous physical activity (MVPA) and cardiorespiratory fitness (CRF) on mortality risk. Limited research has evaluated all three of these parameters in a model when considering mortality risk, and their potential additive association on mortality risk has not been fully evaluated, which was the purpose of this study.

METHODS

Data from the 2003-2006 National Health and Nutrition Examination Survey were used (N = 2,295 adults 20-85 yrs), with follow-up through 2011. Sedentary behavior and MVPA were objectively assessed (accelerometry) with cardiorespiratory estimated from a prediction equation taking into consideration participant demographic, anthropometric and behavioral characteristics. Using the median values, a PACS (Physical Activity Cardiorespiratory Sedentary) score was created that ranged from 0-3, indicating the number of these three positive characteristics.

RESULTS

Those with below median sedentary behavior did not have a reduced all-cause mortality risk (HR = 0.59; 95% CI: 0.34-1.04; P = 0.07), but those with above median MVPA (HR = 0.35; 95% CI: 0.15-0.82; P = 0.02) and above median CRF did (HR = 0.20; 95% CI: 0.09-0.43; P < 0.001). Compared to those with a PACS score of 0, those with a PACS score of 1, 2, and 3, respectively, had a 67% (HR = 0.33; 95% CI: 0.17-0.63, P = 0.002), 82% (HR = 0.12; 95% CI: 0.05-0.30; P < 0.001) and 96% (HR = 0.04; 95% CI: 0.02-0.11; P < 0.001) reduced risk of all-cause mortality.

CONCLUSION

Cardiorespiratory fitness and MVPA, but not sedentary behavior, were independently associated with reduced mortality risk. Adults with all three characteristics (below median sedentary and above median MVPA and CRF), however, had the lowest mortality risk.

Joint effects of objectively-measured sedentary time and physical activity on all-cause mortality

OBJECTIVE

Examine the joint effects of objectively-measured sedentary time and moderate-to-vigorous physical activity (MVPA) on all-cause mortality.

METHODS

The present study included data from the 2003-2006 National Health & Nutrition Examination Survey, with mortality follow-up data (via National Death Index) through 2011 (N=5575U.S. adults). Sedentary time (activity counts/min between 0 and 99) and MVPA (activity counts/min ≥2020) were objectively measured using the ActiGraph 7164 accelerometer.

RESULTS

The median age of the participants was 50yrs; proportion of men was 50.2%; proportion of whites was 53.8%, 18.7% for blacks; median follow-up was 81months; and 511 deaths occurred over the follow-up period. After adjusting for age, gender, race-ethnicity, cotinine, weight status, poverty level, C-reactive protein and comorbid illness (summed score of 0-8 chronic diseases), and for a 1min increase in MVPA and sedentary time, both MVPA (HRadjusted=0.98; 95% CI: 0.96-0.99; P=0.04) and sedentary time (HRadjusted=1.001; 95% CI: 1.0003-1.002; P=0.008) were independently associated with all-cause mortality. Further, MVPA was associated with all-cause mortality among those with greater (above median) sedentary time (HRadjusted=0.95; 95% CI: 0.93-0.97; P<.001). Sedentary time was not associated with all-cause mortality among those engaging in above median levels of MVPA (HRadjusted=0.998; 95% CI: 0.996-1.001; P=.32), but sedentary time was associated with increased mortality risk among those below median levels of MVPA (HR=1.002; 95% CI: 1.001-1.003; P<0.001).

CONCLUSIONS

Sedentary time and MVPA are independently associated with all-cause mortality. Above median sedentary time levels did not negate the beneficial effects of MVPA on all-cause mortality risk.

Objectively measured sedentary behavior and physical activity in a sample of Finnish adults: a cross-sectional study

Background

Regular physical activity (PA) confers many positive effects on health and well-being. Sedentary behavior (SB), in turn, is a risk factor for health, regardless of the level of moderate to vigorous PA. The present study describes the levels of objectively measured SB, breaks in SB, standing still and PA among Finnish adults.

Methods

This cross-sectional analysis is based on the sub-sample of the population-based Health 2011 Study of Finnish adults. The study population consisted of 18-to-85-year old men and women who wore a waist-worn triaxial accelerometer (Hookie AM 20) for at least 4 days, for at least 10 h per day (n = 1587) during a week. PA and SB were objectively assessed from the raw accelerometric data using novel processing and analysis algorithms with mean amplitude deviation as the processing method. The data was statistically analyzed using cross-tabulations, analysis of variance and analysis of covariance.

Results

The participants were on average 52 years old, 57 % being women. Participants were sedentary 59 % of their waking wear time, mainly sitting. They spent 17 % of the time standing still, 15 % in light intensity PA, 9 % in moderate PA and less than 1 % in vigorous PA. Participants aged 30–39 years had the highest number of breaks in SB per day. Younger participants (<30 years of age) had more moderate and vigorous PA than older ones (≥60 years of age), and 30–60-year-olds had the greatest amount of light PA.

Conclusions

Participants spent nearly 60 % of their waking time sedentary, and the majority of their daily PA was light. From a public health perspective it is important to find effective ways to decrease SB as well as to increase the level of PA. Our analysis method of raw accelerometer data may allow more precise assessment of dose-response relationships between objectively measured PA and SB and various indicators of health and well-being.

Physical activity and sedentary behavior in people with bipolar disorder: A systematic review and meta-analysis

BACKGROUND

Mortality rates are approximately two to three times higher in people with bipolar disorder (BD) than in general population. Lack of physical activity (PA) and sedentary behavior (SB) are independent risk factors for cardiovascular disease and premature mortality.

AIMS

We conducted a meta-analysis to investigate PA and SB levels and its predictors in BD.

METHODS

Major electronic databases were searched from inception till 02/2016 for articles measuring PA and SB with a self-report questionnaire (SRQ) or objective measure (e.g. accelerometer) in BD. A random effects meta-analysis and meta-regression analysis were conducted.

RESULTS

Six studies were eligible including 279 (129♂) people with BD (mean age=43.9 years; range: 32.0-51.5 years). The trim and fill analysis demonstrated people with BD spent in total 210.1min (95%CI=146.3-273.9min) per day being physically active and 613.3min (95%CI=389.9-836.6min) during waking hours being sedentary. No significant difference in total PA per day was observed between people with BD and controls (g=-0.62, 95% CI=-1.55 to 0.31, I(2)=88.5%, n BD =82, n controls =86). Objective measures of PA recorded significantly lower levels (P=0.03) compared to self-report PA. Meta-regression demonstrated that older age and a higher body mass index predicted lower PA levels.

LIMITATIONS

Only a limited number of studies were identified assessing SB in people with BD.

CONCLUSIONS

Adults with BD engage in high levels of sedentary behavior during waking hours. Given that sedentary behavior is an independent predictor of cardiovascular disease, future lifestyle interventions specifically targeting the prevention of sedentary behavior are warranted.