Cardiorespiratory fitness in midlife and subsequent incident depression, long-term sickness absence, and disability pension due to depression in 330,247 men and women.

OBJECTIVE: Specific information for whom and when cardiorespiratory fitness (CRF) is associated with depression risk is lacking. We aimed to study the association between adulthood CRF and incident depression, long-term sickness absence, and disability pension due to depression, as well as examine moderation of sex, age, education, and occupation on associations. METHODS: A large prospective cohort study follows participants over time with Swedish occupational health screenings data. The study includes 330,247 individuals (aged 16-79 years, 46% women) without a depression diagnosis at baseline. CRF was estimated from a submaximal cycle test. RESULTS: CRF was associated beneficially from low to higher levels with incident depression and long-term sickness absence due to depression. Further, CRF at high levels (≥46 ml/min/kg) was associated with a decreased risk of receiving disability pension due to depression. The associations remained after adjustment for age and sex, but not lifestyle-related factors and co-morbidity. Participants with moderate and high CRF had 16% and 21%, respectively, lower risk for incident depression, and participants with high CRF had 11% lower risk for long-term sickness absence due to depression. Associations between higher CRF and the outcomes were mainly evident in men, younger participants, and individuals with low education. CONCLUSION: In a large sample of adults without a depression diagnosis at baseline, higher CRF was shown to be beneficially related to the risk of incident depression and, to some extent, long-term sickness absence due to depression. If causal, targeted interventions focusing on increasing CRF in these sub-groups should be prioritized.

Associations between physical activity and ankle-brachial index: the Swedish CArdioPulmonary bioImage Study (SCAPIS).

BACKGROUND: The ankle-brachial index (ABI) is the ratio of the ankle and brachial systolic blood pressures. In the clinical setting, low ABI (< 0.9) is an indicator of peripheral atherosclerosis, while high ABI (> 1.4) is a sign of arterial stiffness and calcification. The purpose of the current study was to investigate the association between ABI and physical activity levels, measured by accelerometer. METHODS: The Swedish CArdioPulmonary bioImage Study (SCAPIS) is a Swedish nationwide population-based cross-sectional cohort for the study of cardiovascular and pulmonary diseases, in which individuals aged 50-64 years were randomly invited from the general population. The study population with data on ABI, physical activity, and sedentary time based on accelerometry was 27,737. Differences between ABI categories and associations to sedentary behavior, moderate to vigorous physical activity (MVPA), and other metabolic characteristics were compared. ABI was categorized as low, ABI ≤ 0.9, borderline, ABI 0.91-0.99, normal, ABI 1.0-1.39, and high, ABI ≥ 1.4. RESULTS: Prevalence of low ABI was higher in the most sedentary quartiles compared to the least sedentary (0.6% vs. 0.1%, p < 0.001). The most sedentary individuals also exhibited higher BMI, higher prevalence of diabetes and hypertension. The proportion of wake time spent in MVPA was lowest in those with low ABI (0.033 ± 0.004; p < 0.001) and highest in those with ABI > 1.4 (0.069 ± 0.001; p < 0.001) compared to those with normal ABI. Compared to normal ABI, the proportion of sedentary time was highest in those with low ABI (0.597 ± 0.012; p < 0.001) and lowest in those with ABI > 1.4 (0.534 ± 0.002; p = 0.004). CONCLUSION: This population-based study shows that middle-aged individuals with ABI > 1.4 have the highest level of physical activity, while individuals with a lower ABI, especially those with ABI < 0.9, are less active and spend more time sedentary. Future studies are needed to understand the relationships between ABI, physical activity, and the risk of peripheral arterial and cardiovascular disease in the general population.

Decrease in accelerometer assessed physical activity during the first-year post-myocardial infarction: a prospective cohort study.

OBJECTIVES: To elucidate physical activity in the first year after myocardial infarction (MI), and to explore differences in various subgroups, delineated by age, participation in exercise-based cardiac rehabilitation (exCR), or restrictions due to the covid-19 pandemic. Secondly, to explore associations between changes in physical activity variables with blood pressure and lipid levels. METHODS: A longitudinal study in 2017-2023. Physical activity variables were assessed via accelerometers at two- and twelve months post-MI. The intensity was divided into, sedentary, light, moderate, and vigorous-intensity physical activity, according to established cut-offs. Blood pressure and lipids were measured by standardized procedures at the same time points. RESULTS: There were 178 patients included at baseline, 81% male, mean age of 64 (9 SD) years. Patients spent 72% of their time sedentary, followed by light (19%), moderate (8%), and vigorous physical activity (1%). Patients included during covid-19 restrictions and younger patients had a higher level of moderate-intensity physical activity compared to patients included during non-pandemic restrictions and older patients. At 12-month follow-up, patients overall increased time (1%) in sedentary behavior (p = 0.03) and decreased time (0.6%) in moderate-intensity physical activity (p = 0.04), regardless of participation in exCR or age. There was a positive association between the change in mean physical activity intensity and HDL-cholesterol (p = 0.047). CONCLUSIONS: Participants had a low fraction of time in moderate-to-vigorous-intensity physical activity two months post-MI, which deteriorated during the first year. This emphasizes the need for improved implementation of evidence-based interventions to support and motivate patients to perform regular physical activity.

Reliability in Novel Field-Based Fitness Measurements and Postexercise Scores from a Physical Fitness Test Battery in Older Adults.

INTRODUCTION: Physical fitness is strongly associated with daily physical function, health, and longevity in older adults. Field-based tests may provide a reasonable alternative compared to advanced laboratory testing. Separating postexercise test scores from reactivity measurements requires sufficient test-retest reliability. Postexercise test scores with reliability analyses of field-based fitness tests in older adults are lacking. The present study aimed to examine the test-retest reliability of some novel easily accommodated fitness test measurements and compare pretest scores with postexercise results in these tests along with other field-based fitness tests in older adults. METHODS: Totally 1,407 community-dwelling older adults (69% female), x̄ = 71.5 ± 5.0 (65-84 years), performed twelve field-based fitness tests at pretest 1, pretest 2 and a posttest after an 8-week exercise period (twice weekly 1 h of combined strength and aerobic training). T tests, intra-class correlation, limits of agreement, standard error of measurement, and coefficient of variance were performed between pre-1 and pre-2 tests, and repeated measures ANOVA and partial eta squared effect size for postexercise differences for men and women in 5-year age groups ranging from 65 to 84 years. RESULTS: Between pre-1 and pre-2 tests a significant difference was noted in some of the novel fitness test measurements but generally not, e.g., in isometric trunk flexion and step-up height on either leg among all sex and age groups. In most of these novel fitness test measurements, no significant differences occurred between the two pretests. Examples of results from the pre-2 test to the posttest were isometric trunk flexion 45° endurance and isometric trunk extension endurance improved significantly for both sexes in age groups 65-74 years. Women, but not men, improved the maximal step-up height for both legs in most age groups. The speed in the 50 sit-to-stand improved significantly for most age groups in both sexes. Six-min walk distance improved significantly for most age groups in women but among men only in 65-69 years. In the timed-up-and-go test, significant improvements were seen for all age groups in women and in men 70-79 years. No postexercise improvements were generally observed for grip strength or balance. CONCLUSIONS: In most of the novel fitness test measures, no significant difference was noted between the two pretests in the assessed sex and age groups. Results after the 8-week exercise period varied between sex and age groups, with significant improvements in several of the twelve studied fitness tests. These findings may be valuable for future projects utilizing easily accommodated physical fitness tests in older adults.

Improving movement behavior in office workers: effects of two multi-level cluster-RCT interventions on mental health.

BACKGROUND: We have previously reported on the design and efficacy of two cluster-randomized multi-level workplace interventions, attempting to decrease sedentary behavior (SED) or increase moderate to vigorous physical activity (MVPA) among office workers to improve mental health outcomes. The aim of this study was to investigate intervention effects on mental health outcomes, i.e., mental wellbeing, depression or anxiety symptoms, and stress immediately after the 6-month intervention period. METHODS: Teams of 263 office workers were cluster-randomized to one of two interventions or a waitlist control group. The PA intervention (iPA) focused on increasing MVPA and the SED intervention (iSED) on reducing SED. Both multi-level interventions targeted individual office workers and their social, physical, and organizational work environment, incorporating counseling based on cognitive behavioral therapy and motivational interviewing. Mental health outcomes were assessed using validated questionnaires before and immediately after the intervention. Intervention effects were analyzed using linear mixed effects models. RESULTS: Participants were mostly female and highly educated, with a mean age of 42 years and had favorable levels of mental health at baseline. Mental wellbeing improved for the iSED group (ß = 8, 95% CI 1 to 15, p = 0.030) but not for the iPA group (ß = 6, 95% CI -1 to 12, p = 0.072) compared to the control group. No effects were found for depression or anxiety symptoms or stress. CONCLUSIONS: The multi-level interventions improved mental wellbeing among this population of office workers, reaching statistical significance in the iSED group. The size of the effect can be regarded meaningful, considering favorable mental health and high PA level at baseline. Thus, workplace interventions that provide support on multiple levels appear to have potential for improving mental wellbeing, but not reducing ill-health variables, among healthy office workers. More research is needed to understand the mechanisms through which such improvements can be achieved and to identify the most effective intervention components. TRIAL REGISTRATION: ISRCTN92968402 (27 February 2018).

Fitness-related physical activity intensity explains most of the association between accelerometer data and cardiometabolic health in persons 50-64 years old.

OBJECTIVES: To investigate the physical activity (PA) intensity associated with cardiometabolic health when considering the mediating role of cardiorespiratory fitness (CRF). METHODS: A subsample of males and females aged 50-64 years from the cross-sectional Swedish CArdioPulmonary bioImage Study was investigated. PA was measured by accelerometry and CRF by a submaximal cycle test. Cardiometabolic risk factors, including waist circumference, systolic blood pressure, high-density lipoprotein, triglycerides and glycated haemoglobin, were combined to a composite score. A mediation model by partial least squares structural equation modelling was used to analyse the role of CRF in the association between PA and the composite score. RESULTS: The cohort included 4185 persons (51.9% female) with a mean age of 57.2 years. CRF mediated 82% of the association between PA and the composite score. The analysis of PA patterns revealed that moderate intensity PA explained most of the variation in the composite score, while vigorous intensity PA explained most of the variation in CRF. When including both PA and CRF as predictors of the composite score, the importance of vigorous intensity increased. CONCLUSION: The highly interconnected role of CRF in the association between PA and cardiometabolic health suggests limited direct effects of PA on cardiometabolic health beyond its impact on CRF. The findings highlight the importance of sufficient PA intensity for the association with CRF, which in turn is linked to better cardiometabolic health.

Associations between physical activity and autonomic function during deep breathing test: the Swedish CArdioPulmonary bioImage Study (SCAPIS).

PURPOSE: The deep breathing test (DBT) is a sensitive test of cardiovagal function. The aim of this study was to explore associations between physical activity and sedentary time, measured by accelerometer, and autonomic function, using DBT. METHODS: In the Swedish Cardio-Pulmonary bioImage Study, men and women aged 50-64 were randomly invited from the general population. A total of 4325 subjects who underwent DBT and assessment of physical activity and sedentary time by accelerometery were included. ECG files from 1-min DBT were used to calculate measures of respiratory sinus arrhythmia [RSA; expiration-inspiration (E-I) difference and E/I ratio], heart rate variability [HRV; root mean square of successive differences (RMSSD), standard deviation of heart rates and mean circular resultant]. Low RSA and HRV was defined as the lowest 10% in the population. RESULTS: For accelerometer-assessed physical activity, there were significant associations between high percentage of sedentary time and low E/I (p < 0.01), and low RMSSD (p < 0.01) in an age- and sex-adjusted model, and between percentage of sedentary time and low RMSSD (p = 0.04) in a risk factor-adjusted model. Low RMSSD was less common in those with a high percentage of moderate to vigorous physical activity (p = 0.04, after risk-factor adjustment). These associations became non-significant when further adjusting for heart rate. CONCLUSION: We report associations between degree of physical activity and indices of autonomic dysfunction in a large population. The relationships were no longer significant after adjustments for heart rate, indicating that the relationship between physical activity and cardiovagal function partly is accounted for by reduced heart rate.

COVID-19 induced changes in physical activity patterns, screen time and sleep among Swedish adolescents - a cohort study.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic had a huge impact on daily life, even in countries such as Sweden where the restrictions were relatively mild. This paper assesses the effects of the COVID-19 pandemic restrictions on physical activity (PA) patterns, screen time, and sleep among Swedish adolescents. The exposures explored include gender, parental education, anthropometrics, and cardiovascular fitness (CVF). METHODS: Cohort data were collected from September 26th to December 6th, 2019, and from April 12th to June 9th, 2021. Participants were 13-14 years-old (7th graders) at baseline with 585 participating at both baseline and follow-up. At both baseline and follow-up PA and sedentary time were measured with accelerometers, and sleep and screen time with questionnaires. The exposure variables (gender, parental education, anthropometrics and CVF) were collected at baseline. Multilevel linear regression analyses were performed. RESULTS: Moderate-to-vigorous-physical activity (MVPA) remained unchanged while light physical activity (LiPA) decreased and sedentary time increased. Sleep duration decreased and screen time increased. Girls, adolescents with overweight/obesity (BMI and percent body fat), and those with lower CVF at baseline had less favourable changes in PA patterns, sleep and screen time. CONCLUSIONS: Although no significant (α = 0.05) changes were seen in MVPA, both LiPA and sedentary time as well as sleep and screen time changed in unfavourable ways. More intense activities are often organised and seem to have withstood the pandemic, while less intense activities decreased. Some groups were more vulnerable and will need directed intervention in the post-pandemic period as well as when future pandemics hit.

Accelerometer-measured absolute versus relative physical activity intensity: cross-sectional associations with cardiometabolic health in midlife.

BACKGROUND: Observational studies investigating the association between accelerometer-measured physical activity and health all use absolute measures of physical activity intensity. However, intervention studies suggest that the physical activity intensity required to improve health is relative to individual fitness. The aim of this study was to investigate the associations between accelerometer-measured absolute and relative physical activity intensity and cardiometabolic health, and what implications these associations may have on the interpretation of health-associated physical activity. METHODS: A sample of the cross-sectional Swedish CArdioPulmonary bioImage Study (SCAPIS) consisting of 4,234 men and women aged 55-64 years was studied. Physical activity intensity was measured by accelerometry and expressed as absolute (e.g., metabolic equivalents of task) or relative (percentage of maximal oxygen consumption). Fitness was estimated by the submaximal Ekblom-Bak test. A composite ('metabolic syndrome') score combined measures of waist circumference, systolic blood pressure, high-density lipoprotein, triglycerides, and glycated hemoglobin. Associations of absolute and relative physical activity intensity with the health indicators (i.e., fitness and metabolic syndrome score) were studied by partial least squares regression. Analyses were stratified by fitness level. RESULTS: Both absolute and relative physical activity intensity associated with the health indicators. However, the strongest associations for absolute intensity varied depending on fitness levels, whereas the associations for relative intensity were more synchronized across fitness groups. The dose-response relationship between moderate-to-vigorous intensity and the health indicators was stronger for relative than for absolute intensity. The absolute and relative moderate-to-vigorous intensity cut-offs intersected at the 5th fitness percentile, indicating that the absolute intensity cut-off is too low for 95% of individuals in this sample. While 99% of individuals fulfilled the general physical activity recommendations based on absolute intensity measures, only 21% fulfilled the recommendations based on relative intensity measures. In relation to a "sufficient" fitness level, 9% fulfilled the recommendations. CONCLUSIONS: Accelerometer-measured relative physical activity intensity represents the intensity related to health benefits regardless of fitness level. Traditional absolute moderate intensity accelerometer cut-offs are too low for most individuals and should be adapted to the fitness level in the sample studied. Absolute and relative physical activity intensity cannot be used interchangeably.

Effects of prolonged sitting and physical activity breaks on measures of arterial stiffness and cortisol in adolescents.

AIM: In adults, prolonged periods of sitting have been linked to acute negative effects on vascular structure and function. The aim of this study was to evaluate the acute effects of physical activity (PA) breaks during prolonged sitting on arterial stiffness, cortisol and psychological factors in adolescents. METHODS: Adolescents underwent different short (3-min) breaks starting every 20 min, during 80 min of sitting on three separate days. Breaks were (A) social seated breaks (SOC), (B) low-intensity simple resistance activity PA breaks (SRA) and (C) moderate-intensity step-up PA breaks (STEP). The arterial stiffness measures were augmentation index (AIx), AIx@75 and pulse wave velocity (PWV). Cortisol was measured from saliva. Psychological factors were self-reported. RESULTS: Eleven girls and six boys (average age 13.6 ± 0.7 years) participated, with average baseline heart rates of 72 ± 11 bpm, systolic/diastolic blood pressure 111 ± 7/64 ± 6 mmHg and cortisol 10.9 ± 5.8 nmoL/L. PWV, cortisol and psychological factors did not change after any of the conditions. AIx@75 increased significantly (4.9 ± 8.7-9.2 ± 13.2) after the STEP intervention compared with SOC and SRA (time × condition p < 0.05). CONCLUSION: Arterial stiffness increased after prolonged sitting with frequent, short step-up activity breaks. The results indicate potential important intensity-dependent effects of physical activity on vascular regulation in youth.

Prevalence of Subclinical Coronary Artery Atherosclerosis in the General Population.

BACKGROUND: Early detection of coronary atherosclerosis using coronary computed tomography angiography (CCTA), in addition to coronary artery calcification (CAC) scoring, may help inform prevention strategies. We used CCTA to determine the prevalence, severity, and characteristics of coronary atherosclerosis and its association with CAC scores in a general population. METHODS: We recruited 30 154 randomly invited individuals age 50 to 64 years to SCAPIS (the Swedish Cardiopulmonary Bioimage Study). The study includes individuals without known coronary heart disease (ie, no previous myocardial infarctions or cardiac procedures) and with high-quality results from CCTA and CAC imaging performed using dedicated dual-source CT scanners. Noncontrast images were scored for CAC. CCTA images were visually read and scored for coronary atherosclerosis per segment (defined as no atherosclerosis, 1% to 49% stenosis, or ≥50% stenosis). External validity of prevalence estimates was evaluated using inverse probability for participation weighting and Swedish register data. RESULTS: In total, 25 182 individuals without known coronary heart disease were included (50.6% women). Any CCTA-detected atherosclerosis was found in 42.1%; any significant stenosis (≥50%) in 5.2%; left main, proximal left anterior descending artery, or 3-vessel disease in 1.9%; and any noncalcified plaques in 8.3% of this population. Onset of atherosclerosis was delayed on average by 10 years in women. Atherosclerosis was more prevalent in older individuals and predominantly found in the proximal left anterior descending artery. Prevalence of CCTA-detected atherosclerosis increased with increasing CAC scores. Among those with a CAC score >400, all had atherosclerosis and 45.7% had significant stenosis. In those with 0 CAC, 5.5% had atherosclerosis and 0.4% had significant stenosis. In participants with 0 CAC and intermediate 10-year risk of atherosclerotic cardiovascular disease according to the pooled cohort equation, 9.2% had CCTA-verified atherosclerosis. Prevalence estimates had excellent external validity and changed marginally when adjusted to the age-matched Swedish background population. CONCLUSIONS: Using CCTA in a large, random sample of the general population without established disease, we showed that silent coronary atherosclerosis is common in this population. High CAC scores convey a significant probability of substantial stenosis, and 0 CAC does not exclude atherosclerosis, particularly in those at higher baseline risk.

Accelerometer derived physical activity patterns in 27.890 middle-aged adults: The SCAPIS cohort study.

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.

Prevalence and time trends of overweight, obesity and severe obesity in 447,925 Swedish adults, 1995-2017.

Aims: The purpose of this research was to describe the current prevalence and historic trends in overweight, obesity and severe obesity in Sweden. Methods: Data on BMI, age, gender, education and geographic region were obtained in n=447,925 Swedish adults through a nationwide screening test (1995-2017). To account for sampling variations, we quantified prevalence estimates and time trends using standardized values (direct method) to all 18-74-year-old Swedes, using nationwide databases. Rates of overweight (BMI ⩾25 kg/m2), obesity (BMI ⩾30 kg/m2) and severe obesity (BMI ⩾35 kg/m2) were calculated across gender, age, education and geographic categories. Years were grouped into two-year sampling periods (except the first period where we used three years) for increased power. We used multivariable logistic regression to quantify independent associations between age, gender, education and region with obesity development and current prevalence rates. Results: In 2016/17 the unstandardized prevalence of overweight, obesity and severe obesity were 55.1%, 16.6% and 4.2%, respectively. Factors associated with a higher obesity prevalence were male gender, older age, lower education and residing in a rural region (all P<0.001). Between 1995 and 2017 the prevalence of severe obesity increased by 153%, compared to obesity (+86%) and overweight (+23%). While there were similar increases in obesity across gender and age groups, people with low education (vs high) and rural areas (vs urban) had a higher prevalence increase (both P<0.001). Conclusions: Rates of overweight, obesity and severe obesity have increased markedly in Swedish adults since 1995. Priority groups for prevention efforts include individuals with low education and those living in rural areas.

The use of coping strategies "shift-persist" mediates associations between physical activity and mental health problems in adolescents: a cross-sectional study.

BACKGROUND: Self-perceived mental health problems among adolescents has had an upward trend. Concurrently, adolescents' physical activity (PA) has been falling whilst sedentary time (SED) has increased. There is a lack of research using accelerometer measured PA and SED to study their relationships to perceived stress and psychosomatic symptoms, both frequently observed mental health problems among adolescents. Whether coping strategies is one of the mechanisms underlying such relationship is less clear. METHODS: A total of 2283 13-year olds were enrolled in the baseline examination of the STARS (STudy of Adolescence Resilience and Stress) study in Western Sweden. Light-, moderate-, vigorous-intensity PA (LPA, MPA and VPA) and SED were measured using hip-worn ActiGraph GT3X+ accelerometer. A total of 1284 adolescents provided valid accelerometer data (at least 4 days with ≥10 h per day). PA and SED during school-time and leisure-time were analysed separately. Surveys were utilized to monitor perceived stress, psychosomatic symptoms and the use of coping strategies "shift-persist". Logistic regression and mediation analyses were performed adjusting for gender, ethnicity, socioeconomic status and puberty development. RESULTS: We observed that more time spent in PA was associated with less stress in adolescents. The associations were observed for LPA (Odds ratio for LPA per 60 min: 0.557 (95% CI 0.399-0.776), VPA (Odds ratio for VPA per 15 min: 0.688 (95% CI 0.588-0.806) and MVPA (Odds ratio for MVPA per 15 min: 0.795 (95%CI 0.718-0.879) during leisure time, but not during school time. Similar associations were observed between leisure time PA and psychosomatic symptoms. The associations remained statistically significant even after adjusting for the confounders. Further, our data showed that adolescents who engaged more time in PA during leisure time were more likely to adopt the coping strategies of "shift-persist". Mediation analysis showed that the use of "shift-persist" mediated the associations between leisure time PA and stress/psychosomatic symptoms. CONCLUSIONS: Leisure time physical activity, irrespective of intensity, may facilitate successful coping with stress and stress-related mental health problems in adolescents.

Detecting prolonged sitting bouts with the ActiGraph GT3X.

The ActiGraph has a high ability to measure physical activity; however, it lacks an accurate posture classification to measure sedentary behavior. The aim of the present study was to develop an ActiGraph (waist-worn, 30 Hz) posture classification to detect prolonged sitting bouts, and to compare the classification to proprietary ActiGraph data. The activPAL, a highly valid posture classification device, served as reference criterion. Both sensors were worn by 38 office workers over a median duration of 9 days. An automated feature selection extracted the relevant signal information for a minute-based posture classification. The machine learning algorithm with optimal feature number to predict the time in prolonged sitting bouts (≥5 and ≥10 minutes) was searched and compared to the activPAL using Bland-Altman statistics. The comparison included optimized and frequently used cut-points (100 and 150 counts per minute (cpm), with and without low-frequency-extension (LFE) filtering). The new algorithm predicted the time in prolonged sitting bouts most accurate (bias ≤ 7 minutes/d). Of all proprietary ActiGraph methods, only 150 cpm without LFE predicted the time in prolonged sitting bouts non-significantly different from the activPAL (bias ≤ 18 minutes/d). However, the frequently used 100 cpm with LFE accurately predicted total sitting time (bias ≤ 7 minutes/d). To study the health effects of ActiGraph measured prolonged sitting, we recommend using the new algorithm. In case a cut-point is used, we recommend 150 cpm without LFE to measure prolonged sitting and 100 cpm with LFE to measure total sitting time. However, both cpm cut-points are not recommended for a detailed bout analysis.

Active commuting in Swedish workers between 1998 and 2015-Trends, characteristics, and cardiovascular disease risk.

BACKGROUND: Trend analyses of active commuting and potential variations in trends and association with cardiovascular disease (CVD) risk within subgroups are unknown. OBJECTIVES: To (a) describe trends in active commuting between 1998 and 2015 and (b) to study the association between different amounts of active commuting and the incidence risk of CVD in a large sample of Swedish workers, and analyses of potential variations across subgroups of socio-demographics, physical activity, and BMI. METHODS: A total of 318 309 participants (47% women, 18-74 years) who participated in a nationwide occupational health service screening between 1998 and 2015 were included. Commuting habits were self-reported, and data on first-time CVD events were derived from national registers. RESULTS: Self-reported passive commuters decreased between 1998 and 2015 (64% to 56%), transferring to an increase in mainly moderate/high-dose active commuters (12% to 19%). Changes were seen in all subgroups. The characteristics and lifestyle habits of the typical passive and active commuter changed little over the study period. Low- and moderate/high-dose active commuters had significantly decreased risks for a first time CVD during follow-up. This was accentuated in men, middle-aged, and in participants with light physical work situations, irregular exercise habits, being overweight/obese, and with low fitness. CONCLUSION: Increases in active commuting were observed between 1998 and 2015, however still leaving a majority who do not actively commute. As active commuting, regardless dose, is associated with a lower CVD risk, encouraging more people to actively commute may provide an easily accessible and time-efficient possibility to increase physical activity and health in the general population.

The effectiveness of multi-component interventions targeting physical activity or sedentary behaviour amongst office workers: a three-arm cluster randomised controlled trial.

BACKGROUND: Interventions to increase physical activity or reduce sedentary behaviour within the workplace setting have shown mixed effects. This cluster randomised controlled trial assessed whether multi-component interventions, focusing on changes at the individual, environmental, and organisational levels, either increased physical activity or reduced sedentary behaviour, compared to a passive control group. METHODS: Teams of office-workers from two companies participated in one of two interventions (iPA: targeting physical activity; or iSED: targeting sedentary behaviour), or wait-list control group (C). Exclusion criterion was very high physical activity level (MVPA ≥30 min/day in ≥10 min bouts every day). Randomisation occurred at the level of workplace cluster, and groups were randomly allocated (1:1) with stratification for company and cluster size. Personnel involved in data collection and processing were blinded to group allocation. Both interventions included five sessions of cognitive behavioural therapy counselling for 6 months. iPA included counselling focused on physical activity, access to a gym, and encouragement to exercise, and go for lunch walks. iSED included counselling on sedentary behaviour and encouragement to reduce sitting and increase engagement in standing- and walking-meetings. At baseline and the 6-month mark accelerometers were worn on the hip and thigh for 7 days. The primary outcomes were group differences in time spent in moderate-to-vigorous intensity physical activity (%MVPA) and in sedentary behaviour (%), analysed using Bayesian multilevel modelling for those with complete data. RESULTS: Two-hundred and sixty three office workers (73% women, mean age 42 ± 9 years, education 15 ± 2 years) were randomised into 23 cluster teams (iPA n = 84, 8 clusters; iSED n = 87, 7 clusters; C n = 92, 7 clusters). No significant group differences (posterior mean ratios: 95% credible interval) were found after the intervention for %MVPA or for %Sedentary. %MVPA: iPA vs C (0·04: - 0·80-0·82); iSED vs C (0·47: - 0·41-1·32); iPA vs iSED (0·43: - 0·42-1·27). %Sedentary: iPA vs C (1·16: - 1·66-4·02); iSED vs C (- 0·44: - 3·50-2·64); iPA vs iSED (- 1·60: - 4·72-1·47). CONCLUSIONS: The multi-component interventions focusing on either physical activity or sedentary behaviour were unsuccessful at increasing device-measured physical activity or reducing sedentary behaviour compared to a control group. TRIAL REGISTRATION: ISRCTN, ISRCTN92968402 . Registered 27/2/2018, recruitment started 15/03/2018.

Criterion validity of the Ekblom-Bak and the Åstrand submaximal test in an elderly population.

PURPOSE: The aim of this study was to validate the submaximal Ekblom-Bak test (EB-test) and the Åstrand test (Å-test) for an elderly population. METHODS: Participants (n = 104), aged 65-75 years, completed a submaximal aerobic test on a cycle ergometer followed by an individually adjusted indirect calorimetry VO2max test on a treadmill. The HR from the submaximal test was used to estimate VO2max using both the EB-test and Å-test equations. RESULTS: The correlation between measured and estimated VO2max using the EB method and Å method in women was r = 0.64 and r = 0.58, respectively and in men r = 0.44 and r = 0.44, respectively. In women, the mean difference between estimated and measured VO2max was - 0.02 L min-1 (95% CI - 0.08 to 0.04) for the EB method and - 0.12 L min-1 (95% CI - 0.22 to - 0.02) for the Å method. Corresponding values for men were 0.05 L min-1 (95% CI - 0.04 to 0.14) and - 0.28 L min-1 (95% CI - 0.42 to - 0.14), respectively. However, the EB method was found to overestimate VO2max in men with low fitness and the Å method was found to underestimate VO2max in both women and men. For women, the coefficient of variance was 11.1%, when using the EB method and 19.8% when using the Å method. Corresponding values for men were 11.6% and 18.9%, respectively. CONCLUSION: The submaximal EB-test is valid for estimating VO2max in elderly women, but not in all elderly men. The Å-test is not valid for estimating VO2max in the elderly.

Organised physical activity during leisure time is associated with more objectively measured physical activity among Swedish adolescents.

AIM: The aim of this study was to investigate associations between participation in organised physical activity (PA), such as sport and exercise during leisure time, and objectively measured PA and sedentary time in a large representative sample of Swedish adolescents. METHODS: This study was part of the school-based cross-sectional Swedish national dietary survey Riksmaten Adolescents 2016-17. Data from 3477 adolescents aged 11-12, 14-15 and 17-18 years were used in the analyses. Participation in organised PA and parental education were reported in questionnaires. PA and sedentary time were objectively measured through accelerometry during seven consecutive days. RESULTS: Adolescents who participated in organised PA had significantly higher total PA (14%, P < .001), more time spent on moderate-to-vigorous PA (MVPA) (8 minutes, P < .001) and had less sedentary time (15 minutes, P < .001). Those who participated in organised PA were more likely to reach recommended PA levels. Total PA and MVPA did not differ by parental education among those who participated in organised PA. CONCLUSION: Adolescents who participated in organised PA were more physically active, less sedentary and more likely to reach PA recommendations than those who did not.

Stronger Association between High Intensity Physical Activity and Cardiometabolic Health with Improved Assessment of the Full Intensity Range Using Accelerometry.

An improved method of physical activity accelerometer data processing, involving a wider frequency filter than the most commonly used ActiGraph filter, has been shown to better capture variations in physical activity intensity in a lab setting. The aim of the study was to investigate how this improved measure of physical activity affected the relationship with markers of cardiometabolic health. Accelerometer data and markers of cardiometabolic health from 725 adults from two samples, LIV 2013 and SCAPIS pilot, were analyzed. The accelerometer data was processed using both the original ActiGraph method with a low-pass cut-off at 1.6 Hz and the improved method with a low-pass cut-off at 10 Hz. The relationship between the physical activity intensity spectrum and a cardiometabolic health composite score was investigated using partial least squares regression. The strongest association between physical activity and cardiometabolic health was shifted towards higher intensities with the 10 Hz output compared to the ActiGraph method. In addition, the total explained variance was higher with the improved method. The 10 Hz output enables correctly measuring and interpreting high intensity physical activity and shows that physical activity at this intensity is stronger related to cardiometabolic health compared to the most commonly used ActiGraph method.