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Objectives: The aim included investigation of the associations between sedentary (SED), low-intensity physical activity (LIPA), moderate-to-vigorous intensity PA (MVPA) and the prevalence of subclinical atherosclerosis in both coronaries and carotids and the estimated difference in prevalence by theoretical reallocation of time in different PA behaviours.

Design: Cross-sectional.

Setting: Multisite study at university hospitals.

Participants: A total of 22 670 participants without cardiovascular disease (51% women, 57.4 years, SD 4.3) from the population-based Swedish CArdioPulmonary bioImage study were included. SED, LIPA and MVPA were assessed by hip-worn accelerometer.

Primary and secondary outcomes: Any and significant subclinical coronary atherosclerosis (CA), Coronary Artery Calcium Score (CACS) and carotid atherosclerosis (CarA) were derived from imaging data from coronary CT angiography and carotid ultrasound.

Results: High daily SED (>70% ≈10.5 hours/day) associated with a higher OR 1.44 (95% CI 1.09 to 1.91), for significant CA, and with lower OR 0.77 (95% CI 0.63 to 0.95), for significant CarA. High LIPA (>55% ≈8 hours/day) associated with lower OR for significant CA 0.70 (95% CI 0.51 to 0.96), and CACS, 0.71 (95% CI 0.51 to 0.97), but with higher OR for CarA 1.41 (95% CI 1.12 to 1.76). MVPA above reference level, >2% ≈20 min/day, associated with lower OR for significant CA (OR range 0.61-0.67), CACS (OR range 0.71-0.75) and CarA (OR range 0.72-0.79). Theoretical replacement of 30 min of SED into an equal amount of MVPA associated with lower OR for significant CA, especially in participants with high SED 0.84 (95% CI 0.76 to 0.96) or low MVPA 0.51 (0.36 to 0.73).

Conclusions: MVPA was associated with a lower risk for significant atherosclerosis in both coronaries and carotids, while the association varied in strength and direction for SED and LIPA, respectively. If causal, clinical implications include avoiding high levels of daily SED and low levels of MVPA to reduce the risk of developing significant subclinical atherosclerosis.

AIMS: Poor exercise capacity and muscle strength in early adulthood are risk factors for cardiovascular disease (CVD). However, it is unclear how these factors relate to subclinical atherosclerosis due to a lack of longitudinal studies. This study investigated whether early adulthood exercise capacity and muscle strength associated with later adulthood subclinical atherosclerosis.

METHODS AND RESULTS: This study included Swedish men (n = 797) who were eligible for military conscription (at ∼18-years of age) and who participated in the baseline assessment of the visualization of asymptomatic atherosclerotic disease for optimum cardiovascular prevention trial between 2013 and 2016 (at 60 years of age). At conscription, isometric muscle strength (dynamometer) and maximum exercise capacity (maximal load cycle ergometer test) were measured. During later adulthood (at 60 years old), the presence of carotid plaques and intima media thickness were measured by using high-resolution ultrasound. At follow-up, plaques were present in 62% (n = 493) of men. Exercise capacity in early adulthood associated with 19% lower odds of plaques [odds ratio (OR) 0.81, 95% confidence interval (CI) 0.68-0.96], independent of muscle strength. This association was not mediated by any single CVD risk factor. However, the total indirect effect of later, but not early, adulthood CVD risk factors was significant, while the direct effect was non-significant (OR 0.85, 95% CI 0.71-1.02). Associations between muscle strength and subclinical atherosclerosis were non-significant.

CONCLUSION: Higher exercise capacity during early adulthood, but not muscle strength, may protect against carotid plaque development during adulthood mediated by the combination rather than a single later adulthood CVD risk factors.

The present study aims to describe accelerometer-assessed physical activity (PA) patterns and fulfillment of PA recommendations in a large sample of middle-aged men and women, and to study differences between subgroups of socio-demographic, socio-economic, and lifestyle-related variables. A total of 27 890 (92.5% of total participants, 52% women, aged 50–64 years) middle-aged men and women with at least four days of valid hip-worn accelerometer data (Actigraph GT3X+, wGT3X+ and wGT3X-BT) from the Swedish CArdioPulmonary bioImage Study, SCAPIS, were included. In total, 54.5% of daily wear time was spent sedentary, 39.1% in low, 5.4% in moderate, and only 0.1% in vigorous PA. Male sex, higher education, low financial strain, born in Sweden, and sedentary/light working situation were related to higher sedentary time, but also higher levels of vigorous PA. High BMI and having multiple chronic diseases associated strongly with higher sedentary time and less time in all three PA intensities. All-year physically active commuters had an overall more active PA pattern. The proportion fulfilling current PA recommendations varied substantially (1.4% to 92.2%) depending on data handling procedures and definition used. Twenty-eight percent was defined as having an “at-risk” behavior, which included both high sedentary time and low vigorous PA. In this large population-based sample, a majority of time was spent sedentary and only a fraction in vigorous PA, with clinically important variations between subgroups. This study provides important reference material and emphasizes the importance of a comprehensive assessment of all aspects of the individual PA pattern in future research and clinical practice.

Time spent in sedentary behavior (SB) has increased during the last decades. Accurate assessments are of importance when studying health consequences of SB. This study aimed to assess concurrent validity between three different questions for self-reported sitting and thigh worn accelerometer data. In total, 86 participants wore the ActivPAL accelerometer during three separate weeks, assessing sitting time with different questions each week. The questions used were Katzmarzyk, GIH stationary single-item question (SED-GIH), and a modified version of the singleitem from IPAQ short form. In total 64, 57, and 55 participants provided valid accelerometer and questionnaire data at each time-point, respectively, and were included for analysis. Spearman and Pearson correlation was used to assess the validity. The three questions, Katzmarzyk, SED-GIH, and a modified question from IPAQ all showed a weak non-significant correlation to ActivPAL with r-values of 0.26, 0.25, and 0.19 respectively. For Katzmarzyk and SED-GIH, 50% and 37% reported correctly, respectively. For the modified IPAQ, 53% over-reported and 47% under-reported their sitting time. In line with previous research, our study shows poor validity for self-reported sitting-time. For future research, the use of sensor-based data on SB are of high importance.

One way to increase physical activity in offices is to install treadmill workstations, whereoffice workers can walk on a treadmill while performing their normal tasks. However, theexperiences of people using these treadmill workstations over a long period of time is notknown. In this 13-month study, we explored the experiences of office workers with treadmillworkstations available in their offices. After completing a larger randomized controlled trialwith 80 office workers ages 40 to 67 years with overweight or obesity, we interviewed 20 participantsfrom the intervention group, using a semi-structured interview guide. Data wereanalyzed using a grounded theory approach with constant comparison of emerging codes,subcategories, and categories, followed by connecting the categories to create a core category.The core category is described as the “Ability to benefit.” Although all participants hada rather high motivational level and pre-existing knowledge about the health benefits ofincreasing physical activity at work, they had different capacities for benefiting from the intervention.The categories are described as ideal types: the Convinced, the Competitive, theResponsible, and the Vacillating. These ideal types do not represent any single participantbut suggest generalized abstractions of experiences and strategies emerging from the codingof the interviews. One participant could easily have more than one ideal type. Becauseof differences in ideal type strategies and paths used throughout the course of the study,participants had different abilities to benefit from the intervention. Knowledge regarding theideal types may be applied to facilitate the use of the treadmill workstations. Because differentideal types might require different prompts for behavior change, tailored interventionstrategies directed towards specific ideal types could be necessary.

Objectives: To investigate the long-term effects on cognition and brain function after installing treadmill workstations in offices for 13 months.

Methods: Eighty healthy overweight or obese office workers aged 40–67 years were individually randomized to an intervention group, receiving a treadmill workstation and encouraging emails, or to a control group, continuing to work as usual. Effects on cognitive function, hippocampal volume, prefrontal cortex (PFC) thickness, and circulating brain-derived neurotrophic factor (BDNF) were analyzed. Further, mediation analyses between changes in walking time and light-intensity physical activity (LPA) on changes in BDNF and hippocampal volume between baseline and 13 months, and multivariate analyses of the baseline data with percentage sitting time as the response variable, were performed.

Results: No group by time interactions were observed for any of the outcomes. In the mediation analyses, positive associations between changes in walking time and LPA on changes in hippocampal volume were observed, although not mediated by changes in BDNF levels. In the multivariate analyses, a negative association between percentage sitting time and hippocampal volume was observed, however only among those older than 51 years of age.

Conclusion: Although no group by time interactions were observed, our analyses suggest that increased walking and LPA may have positive effects on hippocampal volume and that sedentary behavior is associated with brain structures of importance for memory functions.

Trial Registration: www.ClinicalTrials.gov as NCT01997970.

Objectives: The aim of this study was to investigate effects of a multicomponent program promoting physical activity on sedentary behavior, physical activity, and body measures, when relocating from cell offices to either a flex or cell office.

Methods: The Active Office Design (AOD) study is a longitudinal non-randomized controlled study performed in a municipality in northern Sweden. A subsample of 86 participants were randomly recruited from the AOD study to objectively measure sedentary behavior and physical activity, using ActivPAL and ActiGraph, before and after relocation to the two different office types. The multicomponent program promoting physical activity was performed in both offices. Data were analyzed using linear mixed models.

Results: Eighteen months after relocation, the total number of steps per work day increased by 21% in the flex office and 3% in the cell office group, compared to baseline. Moderate and vigorous physical activity (MVPA) during work hours increased by 42% in the flex office group and 19% in the cell office group. No changes were seen regarding sitting time at work. Small additive effects for walking and MVPA were seen for both groups during non-work time. Weight increased in the flex office group.

Conclusions: This long-term study shows that a multicomponent workplace intervention can lead to increased walking time, steps, and MVPA in a flex compared to a cell office. Small additive increases of physical activity were seen during non-work time in both groups. More long-term controlled studies are needed to confirm these results.

Background: Modern society is triggering sedentary behaviours in different domains. Different strategies can be used to reduce the time spent sitting and increase physical activity in the office environment, which is one domain where sedentary time is often high. One such strategy could be to install treadmill workstations. With these, the office workers can walk on a treadmill while performing their usual work tasks at the computer. However, the long-term effects of these workstations are not known. 

Aim: The overall aim of this thesis was to investigate the long-term effects on sedentary behaviour, physical activity and associated health factors of installing treadmill workstations in offices compared to regular office work.

Method: In this randomized controlled trial, 80 sedentary, middle-aged, healthy office workers with overweight or obesity were individually randomized into either an intervention or a control group. Those in the intervention group had a treadmill workstation installed at their sit-stand desk, to use for at least one hour per day for 13 months. They further received boosting e-mails at four time-points during the study. Participants in the control group continued to work as normal at their sit-stand office desk. All participants also received a health consultation at the beginning of the study, where they got to discuss physical activity and diet recommendations. Measurements reported include physical activity and sedentary behaviour, anthropometric measurements, body composition, metabolic outcomes, stress, depression and anxiety, cognitive function, structural brain images and interview data. Linear mixed models were used for the main statistical analyses of the quantitative data. An exploratory approach was also undertaken, using orthogonal partial least squares regression on the baseline data. Finally, interview data from participants in the intervention group were analysed using a modified Grounded Theory approach.

Results: The intervention group increased their daily walking time and their number of steps at all follow-ups compared to the control group. Concomitantly, a decrease in moderate-to-vigorous intensity physical activity (MVPA) was observed within both groups, mainly during weekends. No intervention effects were observed on any of the body, cognitive or brain volume measurements. Our exploratory analyses revealed a significant association between smaller hippocampal volume and percentage sitting time among participants over 51 years of age. From the interview data, we discovered a core category, “The Capacity to Benefit”. The categories were described as the ideal types the Convinced, the Competitive, the Responsible and the Vacillating, based on the principal characteristics of the participants representing their different motivational status and strategies to reach the goal of benefitting from the intervention.  

Conclusion: It is possible to increase daily physical activity in office environments by introducing treadmill workstations. Future interventions should adapt strategies for the individuals based on their motivational level, but should also workwith the social and physical environment and with factors within the organization to gain the best effects of these interventions.

PURPOSE: Our primary hypothesis was that an intervention with treadmill workstations would increase time spent walking. Secondary hypotheses were a decrease in time spent sitting with a concomitant increase in time spent standing and in light intensity physical activity (LPA) leading to positive effects on body measurements and body composition.

METHODS: The intervention group received a treadmill workstation at their office desk during 13 months. Daily time spent sitting, standing and walking and number of steps was measured with activPAL^®. Daily time in LPA and MVPA was measured with Actigraph^®. Body weight, BMI and waist circumference were measured according to standardized protocols. Dual X-ray Absorptiometry was used to estimate body composition. Mixed models was used for the statistical analysis, with group, day of week (weekday/ weekend), time point and gender as fixed effects and age as a covariate. p<0.05 was considered significant.

RESULTS: Eighty participants were included. The intervention group significantly increased their time spent walking at all follow-ups, with a difference at 13 months of 22 minutes (p<0.01) and 1645 steps per day (p<0.05), respectively, versus controls. Concomitantly, they decreased their MVPA with 13 minutes per day (p<0.001) at weekdays at 13 months versus baseline. We also found a decrease in LPA with 19 minutes per day (p<0.05), and of 17 minutes per day for MVPA (p<0.001) at 13 months versus baseline at weekends. The control group increased their time spent sitting with 25 minutes per day (p<0.05) and decreased the time spent standing with 35 minutes per day at weekdays (p<0.001) compared to baseline. There was also a decrease in LPA with 14 minutes per day (p<0.01) and in MVPA with 6 minutes per day (p<0.01) versus baseline during weekdays, with a decrease in sitting time with 36 minutes (p<0.05) at weekends. There were no significant changes in body measurements or body composition.

CONCLUSION: It is possible to increase daily walking time by introducing treadmill workstations at offices. A decreased MVPA within the intervention group may contribute to lack of effects on body measurements and body composition. It is therefore important that future interventions aim at both reducing sedentary time as well as increasing, or at least remaining, MVPA levels.