Sitting and chronic disease: where do we go from here?

KW is supported by a British Heart Foundation Intermediate Basic Science Research Fellowship (grant number FS/12/58/29709) and the UK Medical Research Council (grant number MC_UU_12015/3). GNH is supported by an Australian National Health and Medical Research Council Career Development Fellowship (grant number 108029).This is the author accepted manuscript. The final version is available from Springer via http://dx.doi.org/10.1007/s00125-016-3886-

Physical Activity Surveillance Through Smartphone Apps and Wearable Trackers: Examining the UK Potential for Nationally Representative Sampling.

BACKGROUND: Smartphones and wearable activity trackers present opportunities for large-scale physical activity (PA) surveillance that overcome some limitations of questionnaires or researcher-administered devices. However, it remains unknown whether current users of such technologies are representative of the UK population. OBJECTIVE: The objective of this study was to investigate potential sociodemographic biases in individuals using, or with the potential to use, smartphone apps or wearable activity trackers for PA surveillance in the United Kingdom. METHODS: We used data of adults (aged ≥16 years) from two nationally representative surveys. Using the UK-wide 2018 Ofcom Technology Tracker (unweighted N=3688), we derived mutually adjusted odds ratios (ORs; 95% CI) of personal use or household ownership of a smartwatch or fitness tracker and personal use of a smartphone by age, sex, social grade, activity- or work-limiting disability, urban or rural, and home nation. Using the 2016 Health Survey for England (unweighted N=4539), we derived mutually adjusted ORs of the use of wearable trackers or websites or smartphone apps for weight management. The explanatory variables were age, sex, PA, deprivation, and body mass index (BMI). Furthermore, we stratified these analyses by BMI, as these questions were asked in the context of weight management. RESULTS: Smartphone use was the most prevalent of all technology outcomes, with 79.01% (weighted 2085/2639) of the Technology Tracker sample responding affirmatively. All other outcomes were <30% prevalent. Age ≥65 years was the strongest inverse correlate of all outcomes (eg, OR 0.03, 95% CI 0.02-0.05 for smartphone use compared with those aged 16-44 years). In addition, lower social grade and activity- or work-limiting disability were inversely associated with all Technology Tracker outcomes. Physical inactivity and male sex were inversely associated with both outcomes assessed in the Health Survey for England; higher levels of deprivation were only inversely associated with websites or phone apps used for weight management. The conclusions did not differ meaningfully in the BMI-stratified analyses, except for deprivation that showed stronger inverse associations with website or phone app use in the obese. CONCLUSIONS: The sole use of PA data from wearable trackers or smartphone apps for UK national surveillance is premature, as those using these technologies are more active, younger, and more affluent than those who do not

Dietary factors associated with obesity indicators and level of sports participation in Flemish adults : a cross-sectional study

BACKGROUND: Obesity develops when energy intake continuously exceeds energy expenditure, causing a fundamental chronic energy imbalance. Societal and behavioural changes over the last decades are held responsible for the considerable increase in sedentary lifestyles and inappropriate dietary patterns. The role of dietary fat and other dietary factors in the aetiology and maintenance of excess weight is controversial. The purposes of the present study were to investigate the dietary factors associated with body mass index (BMI) and waist circumference (WC), and to analyse whether dietary intake varies between subjects with different levels of sports participation. METHODS: Data for this cross-sectional study, including anthropometric measurements, 3-day diet diary and physical activity questionnaire, were collected by the Flemish Policy Research Centre Sport, Physical Activity and Health (SPAH) between October 2002 and April 2004. Results of 485 adult men and 362 women with plausible dietary records were analysed. Analyses of covariance were performed to determine the differences in dietary intake between normal weight, overweight and obese subjects, and between subjects with different levels of sports participation. RESULTS: Total energy intake, protein and fat intake (kcal/day) were significantly higher in obese subjects compared to their lean counterparts in both genders. Percentage of energy intake from fat was significantly higher in obese men compared to men with normal weight or WC. Energy percentages from carbohydrates and fibres were negatively related to BMI and WC in men, whereas in women a higher carbohydrate and fibre intake was positively associated with obesity. Alcohol intake was positively associated with WC in men. Subjects participating in health related sports reported higher intake of carbohydrates, but lower intake of fat compared to subjects not participating in sports. CONCLUSION: This study supports the evidence that carbohydrate, fat, protein and fibre intake are closely related to BMI and WC. The sex differences for dietary intake between obese men and women might reflect the generally higher health consciousness of women. Alcohol intake was only associated with WC, emphasizing the importance of WC as an additional indicator in epidemiological studies. Besides enhancing sports and physical activity, it is necessary to improve the knowledge about nutrition and to promote the well-balanced consumption of wholesome food

Reliability and validity of a domain-specific last 7-d sedentary time questionnaire

Purpose: The objective of this study is to examine test-retest reliability, criterion validity, and absolute agreement of a self-report, last 7-d sedentary behavior questionnaire (SIT-Q-7d), which assesses total daily sedentary time as an aggregate of sitting/lying down in five domains (meals, transportation, occupation, nonoccupational screen time, and other sedentary time). Dutch (DQ) and English (EQ) versions of the questionnaire were examined. Methods: Fifty-one Flemish adults (ages 39.4 +/- 11.1 yr) wore a thigh accelerometer (activPAL3 (TM)) and simultaneously kept a domain log for 7 d. The DQ was subsequently completed twice (median test-retest interval: 3.3 wk). Thigh-acceleration sedentary time was log annotated to create comparable domain-specific and total sedentary time variables. Four hundred two English adults (ages 49.6 +/- 7.3 yr) wore a combined accelerometer and HR monitor (Actiheart (R)) for 6 d to objectively measure total sedentary time. The EQ was subsequently completed twice (median test-retest interval: 3.4 wk). In both samples, the questionnaire reference frame overlapped with the criterion measure administration period. All participants had five or more valid days of criterion data, including one or more weekend day. Results: Test-retest reliability (intraclass correlation coefficient (95% CI)) was fair to good for total sedentary time (DQ: 0.68 (0.50-0.81); EQ: 0.53 (0.44-0.62)) and poor to excellent for domain-specific sedentary time (DQ: from 0.36 (0.10-0.57) (meals) to 0.66 (0.46-0.79) (occupation); EQ: from 0.45 (0.35-0.54) (other sedentary time) to 0.76 (0.71-0.81) (meals)). For criterion validity (Spearman rho), significant correlations were found for total sedentary time (DQ: 0.52; EQ: 0.22; all P <0.001). Compared with domain-specific criterion variables (DQ), modest-to-strong correlations were found for domain-specific sedentary time (from 0.21 (meals) to 0.76 (P < 0.001) (screen time)). The questionnaire generally overestimated sedentary time compared with criterion measures. Conclusion: The SIT-Q-7d appears to be a useful tool for ranking individuals in large-scale observational studies examining total and domain-specific sitting

Metabolic syndrome risk and mental health: Relationship with physical activity and physical fitness in Flemish adults

Het metabool syndroom vertoont wereldwijd een hoge, stijgende prevalentie, en gaat gepaard met een verhoogd risico op cardiovasculaire aandoeningen, type II diabetes en vroegtijdige dood. Psychologische stress vormt eveneens een belangrijke publieke gezondheidsbedreiging omwille van de hoge prevalentie en de geassocieerde gezondheidsrisico’s, waaronder depressie, angststoornissen, en het metabool syndroom. Op basis van bepaalde biologische processen, zouden, naast stress, ook fysieke activiteit en fysieke fitheid, een causale rol kunnen hebben in de ontwikkeling van het metabool syndroom. Bovendien ondersteunen bepaalde theorieën mogelijke positieve effecten van fysieke activiteit op stress. De studie van de onderlinge relaties tussen fysieke activiteit, fysieke fitheid, stress en het metabool syndroom is dus een belangrijke bron van informatie voor de ontwikkeling van effectieve preventiestrategieën tegen stress en het metabool syndroom. Het voornaamste doel van deze thesis bestond eruit deze onderlinge relaties te onderzoeken in een populatie van Vlaamse volwassenen tussen 18 en 75 jaar. Voorafgaand werden echter een aantal computergestuurde psychologische vragenlijsten en een nieuw geconstrueerde continue risicoscore voor het metabool syndroom onderzocht op respectievelijk betrouwbaarheid en validiteit. De eerste studie toonde aan dat de computergestuurde versie van vijf verschillende psychologische gezondheidsvragenlijsten als een betrouwbaar alternatief voor de originele versie mag gebruikt worden in een algemene volwassen populatie. Vervolgens werd aangetoond dat een continue risicoscore van het metabool syndroom, geconstrueerd om een aantal beperkingen van reeds bestaande binaire definities op te vangen, een valide instrument is voor epidemiologisch onderzoek. In de vier relatiestudies konden we, evenwel hun cross-sectioneel karakter in het achterhoofd houdend, vooreerst besluiten dat sportparticipatie door middel van positieve effecten op sociale steun en coping, een vermindering van stress, angst en depressie kan veroorzaken. Verder kan een vermindering van sedentair gedrag resulteren in een risicoverlaging voor het metabool syndroom, supplementair op een risicoverlaging door een toename in matige tot intense fysieke activiteit. Wat betreft fysieke fitheid kan een hogere spierkracht bij vrouwen eveneens beschermend zijn tegen het metabool syndroom, bovenop een beschermend effect van een goede aerobe fitheid, terwijl bij mannen enkel een mogelijk beschermend effect van aerobe fitheid tegen het metabool syndroom werd gevonden. Tenslotte toonde een causaal model aan dat het beschermend effect van matige tot intense fysieke activiteit tegen het metabool syndroom voornamelijk zou veroorzaakt worden door een toename in fysieke fitheid

Standing up against office sitting: A study protocol.

BACKGROUND: Sedentary behaviour is associated with cardiometabolic diseases amongst office-bound workers, mostly through extended sitting and engaging in low-energy-demanding activities during work hours. The aim of this study is to assess the effectiveness of standing desks and healthy messages on cardiovascular parameters in a cohort of office-based workers and to explore the perceptions of these workers about the suitability of this intervention to lower occupation-related sedentariness. METHODS/DESIGN: The protocol will use a mixed-methods study design. Phase 1 of this study is a 12-month, single blinded, randomised controlled trial, which will include baseline, 3-month, 6-month and 12-month post-intervention assessments of plausible cardiometabolic risk biomarkers in office-bound workers at a South African credit and information management company. These biomarkers include anthropometry, sedentary behaviour and physical activity, sleep duration, blood pressure, glucose, glycated haemoglobin (HbA1c), lipid profile and cardiorespiratory fitness. Participants will be randomised into an intervention or control group. The intervention group will be provided with an adjustable sit-stand desk and receive weekly health-promoting messages for the intervention period. Phase 2 will use focus group discussions conducted post-intervention to explore the study participants' perceptions of the effectiveness of the intervention. Cardiometabolic risk biomarkers and changes in these variables will be compared between the intervention group and the control group at the four time points using descriptive and inferential statistics. DISCUSSION: Regression analysis will be undertaken to determine the association of cardiometabolic risk biomarkers with cardiometabolic diseases. A thematic content analysis approach will be used to explore emerging themes from focus group discussions. PROTOCOL IDENTIFICATION: Pan African Clinical Trial Registry, PACTR201911656014962

Impact of sit-stand desks at work on energy expenditure and sedentary time: protocol for a feasibility study.

BACKGROUND: Prolonged sitting, an independent risk factor for disease development and premature mortality, is increasing in prevalence in high- and middle-income countries, with no signs of abating. Adults in such countries spend the largest proportion of their day in sedentary behaviour, most of which is accumulated at work. One promising method for reducing workplace sitting is the use of sit-stand desks. However, key uncertainties remain about this intervention, related to the quality of existing studies and a lack of focus on key outcomes, including energy expenditure. We are planning a randomised controlled trial to assess the impact of sit-stand desks at work on energy expenditure and sitting time in the short and longer term. To reduce the uncertainties related to the design of this trial, we propose a preliminary study to assess the feasibility and acceptability of the recruitment, allocation, measurement, retention and intervention procedures. METHODS: Five hundred office-based employees from two companies in Cambridge, UK, will complete a survey to assess their interest in participating in a trial on the use of sit-stand desks at work. The workspaces of 100 of those interested in participating will be assessed for sit-stand desk installation suitability, and 20 participants will be randomised to either the use of sit-stand desks at work for 3 months or a waiting list control group. Energy expenditure and sitting time, measured via Actiheart and activPAL monitors, respectively, as well as cardio-metabolic and anthropometric outcomes and other outcomes relating to health and work performance, will be assessed in 10 randomly selected participants. All participants will also be interviewed about their experience of using the desks and participating in the study. DISCUSSION: The findings are expected to inform the design of a trial assessing the impact of sit-stand desks at work on short and longer term workplace sitting, taking into account their impact on energy expenditure and the extent to which their use has compensation effects outside the workplace. The findings from such a trial are expected to inform discussions regarding the potential of sit-stand desks at work to alleviate the harm to cardio-metabolic health arising from prolonged sitting. TRIAL REGISTRATION: ISRCTN44827407.This work was supported by a grant from the Department of Health Policy Research Program (Policy Research Unit in Behaviour and Health [PR-UN-0409-10109]), the Medical Research Council (Unit Programme number MC_UU_12015/3) and the British Heart Foundation (Intermediate Basic Science Research Fellowship grant FS/12/58/29709 to KW)

Ten-year change in sedentary behaviour, moderate-to-vigorous physical activity, cardiorespiratory fitness and cardiometabolic risk: independent associations and mediation analysis.

BACKGROUND: We aimed to study the independent associations of 10-year change in sedentary behaviour (SB), moderate-to-vigorous physical activity (MVPA) and objectively measured cardiorespiratory fitness (CRF), with concurrent change in clustered cardiometabolic risk and its individual components (waist circumference, fasting glucose, high-density lipoprotein (HDL) cholesterol, triglycerides and blood pressure). We also determined whether associations were mediated by change in CRF (for SB and MVPA), waist circumference (for SB, MVPA and CRF) and dietary intake (for SB). METHODS: A population-based sample of 425 adults (age (mean±SD) 55.83±9.40; 65% men) was followed prospectively for 9.62±0.52 years. Participants self-reported SB and MVPA and performed a maximal cycle ergometer test to estimate peak oxygen uptake at baseline (2002-2004) and follow-up (2012-2014). Multiple linear regression and the product of coefficients method were used to examine independent associations and mediation effects, respectively. RESULTS: Greater increase in SB was associated with more detrimental change in clustered cardiometabolic risk, waist circumference, HDL cholesterol and triglycerides, independently of change in MVPA. Greater decrease in MVPA was associated with greater decrease in HDL cholesterol and increase in clustered cardiometabolic risk, waist circumference and fasting glucose, independent of change in SB. Greater decrease in CRF was associated with more detrimental change in clustered cardiometabolic risk and all individual components. Change in CRF mediated the associations of change in SB and MVPA with change in clustered cardiometabolic risk, waist circumference and, only for MVPA, HDL cholesterol. Change in waist circumference mediated the associations between change in CRF and change in clustered cardiometabolic risk, fasting glucose, HDL cholesterol and triglycerides. CONCLUSIONS: A combination of decreasing SB and increasing MVPA, resulting in positive change in CRF, is likely to be most beneficial towards cardiometabolic health.This work was supported by a British Heart Foundation Intermediate Basic Science Research Fellowship to KW (grant number FS/12/58/29709), the UK Medical Research Council (grant number MC_UU_12015/3) to KW, the Research Foundation Flanders (grant number G.0194.11N) and the Flemish Policy Research Centre Sport