An Exploration of Sedentary Behavior Patterns in Community-Dwelling People With Stroke: A Cluster-Based Analysis.

BACKGROUND AND PURPOSE: Long periods of daily sedentary time, particularly accumulated in long uninterrupted bouts, are a risk factor for cardiovascular disease. People with stroke are at high risk of recurrent events and prolonged sedentary time may increase this risk. We aimed to explore how people with stroke distribute their periods of sedentary behavior, which factors influence this distribution, and whether sedentary behavior clusters can be distinguished? METHODS: This was a secondary analysis of original accelerometry data from adults with stroke living in the community. We conducted data-driven clustering analyses to identify unique accumulation patterns of sedentary time across participants, followed by multinomial logistical regression to determine the association between the clusters, and the total amount of sedentary time, age, gender, body mass index (BMI), walking speed, and wake time. RESULTS: Participants in the highest quartile of total sedentary time accumulated a significantly higher proportion of their sedentary time in prolonged bouts (P < 0.001). Six unique accumulation patterns were identified, all of which were characterized by high sedentary time. Total sedentary time, age, gender, BMI, and walking speed were significantly associated with the probability of a person being in a specific accumulation pattern cluster, P < 0.001 - P = 0.002. DISCUSSION AND CONCLUSIONS: Although unique accumulation patterns were identified, there is not just one accumulation pattern for high sedentary time. This suggests that interventions to reduce sedentary time must be individually tailored.Video Abstract available for more insight from the authors (see the Video Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A343).

The Feasibility and Longitudinal Effects of a Home-Based Sedentary Behavior Change Intervention After Stroke.

OBJECTIVE: To evaluate the feasibility and preliminary effects of a sedentary behavior change intervention on sedentary behavior, physical activity, function, and quality of life following inpatient stroke rehabilitation. DESIGN: Single-group, longitudinal, intervention study with 1-week baseline, 8-week intervention, and 8-week follow-up. SETTING: Community. PARTICIPANTS: Individuals (N=34) with subacute stroke recruited within 1 month following discharge home from inpatient stroke rehabilitation. INTERVENTION: STand Up Frequently From Stroke (STUFFS) intervention that involved interrupting and replacing sedentary time with upright activities (standing and walking) at home and in the community. A motivational wrist-worn activity monitor was used throughout the intervention. MAIN OUTCOME MEASURES: Primary outcomes were reach (enrolled/eligible), retention (completed/enrolled), satisfaction, and compliance with the intervention. Secondary outcomes were sedentary behavior, physical activity, lower extremity impairment, self-efficacy, cognitive status, mobility, and quality of life outcomes. RESULTS: Forty-four participants were eligible to participate. Of the eligible, 34 (77.3%; time since stroke onset: 3.5±1.1 months) were enrolled at baseline and 32 (94.1%) of the enrolled had complete data at follow-up. Satisfaction with the program was 89%. Sedentary time decreased by 54.2±13.7 minutes per day (P<.01) at postintervention and 26.8±14.0 minutes per day (P=.07) at follow-up, relative to baseline. There were significant improvements in walking speed, cognition, impairment, and self-reported quality of life over time (P<.05). Self-efficacy was high across all time points. The number of steps and time spent stepping were not statistically different across both time periods. CONCLUSIONS: The program was feasible to deliver in the home environment with good retention and satisfaction. Further research is required to test the effectiveness of the STUFFS program compared with usual care.

Sleep Duration, Sedentary Behavior, Physical Activity, and Quality of Life after Inpatient Stroke Rehabilitation.

OBJECTIVE: The aim of this study was to describe accelerometer-derived sleep duration, sedentary behavior, physical activity, and quality of life and their association with demographic and clinical factors within the first month after inpatient stroke rehabilitation. MATERIALS AND METHODS: Thirty people with stroke (mean ± standard deviation, age: 63.8 ± 12.3 years, time since stroke: 3.6 ± 1.1 months) wore an activPAL3 Micro accelerometer (PAL Technologies, Glasgow, Scotland) continuously for 7 days to measure whole-day activity behavior. The Stroke Impact Scale and the Functional Independence Measure were used to assess quality of life and function, respectively. RESULTS: Sleep duration ranged from 6.6 to 11.6 hours/day. Fifteen participants engaged in long sleep greater than 9 hours/day. Participants spent 74.8% of waking hours in sedentary behavior, 17.9% standing, and 7.3% stepping. Of stepping time, only a median of 1.1 (interquartile range: .3-5.8) minutes were spent walking at a moderate-to-vigorous intensity (≥100 steps/minute). The time spent sedentary, the stepping time, and the number of steps differed significantly by the hemiparetic side (P < .05), but not by sex or the type of stroke. There were moderate to strong correlations between the stepping time and the number of steps with gait speed (Spearman r = .49 and .61 respectively, P < .01). Correlations between accelerometer-derived variables and age, time since stroke, and cognition were not significant. CONCLUSIONS: People with stroke sleep for longer than the normal duration, spend about three quarters of their waking hours in sedentary behaviors, and engage in minimal walking following stroke rehabilitation. Our findings provide a rationale for the development of behavior change strategies after stroke.

Compositional associations between movement-related behaviours and functional outcomes post-stroke.

PURPOSE: To examine the associations between the composition of movement-related behaviours (sedentary behaviour, sleep, standing, and stepping) and functional outcomes post-stroke. METHODS: This study included 34 adults with stroke (mean age: 64.6 ± 12.5 years; time since stroke: 3.5 ± 1.1 months) who underwent an 8-week sedentary behaviour intervention. Functional outcomes were assessed using the timed up and go (TUG) and gait speed tests. Compositional data analysis was used to investigate the relationships between movement-related behaviours and functional outcomes. RESULTS: The baseline composition of movement-related behaviours showed significant associations with changes in TUG (F = 4.28, p = 0.01) and gait speed (F = 4.63, p = 0.01) after the 8-week reducing sedentary behaviour intervention. Reallocating ≥ 30 min/day to stepping, while proportionally decreasing other movement-related behaviours, was associated with a significant change in TUG. Similarly, a relative reallocation of ≥ 40 min/day to stepping was associated with a clinically meaningful change in gait speed. CONCLUSIONS: This study highlights the importance of considering movement-related behaviours in relation to functional outcomes post-stroke. Reallocating at least 30 min per day to stepping, relative to a reduction in other movement-related behaviours, is associated with significant and meaningful change in functional outcomes.

Reallocating at least 30 minutes/day to stepping, relative to a decrease in other movement-related behaviours, is associated with a positive change in functional mobility after an 8-week post-stroke sedentary behaviour intervention.Relative to a decrease in other movement-behaviours, reallocating ≥ 40 minutes/day to stepping is associated with a meaningful change in gait speed.Reallocating time to standing or sleep at the expense of other movement behaviours is not associated with better functional mobility or gait speed.Finding the optimal balance in movement-related behaviours that favours more stepping may lead to improvements in both functional mobility and gait speed.

A systematic review of the associations between sedentary behavior, physical inactivity, and non-motor symptoms of Parkinson's disease.

BACKGROUND: Parkinson's disease (PD), known for motor symptoms, often presents early non-motor issues that significantly affect patients' quality of life. While effective treatments are limited, physical activity and exercise offer potential benefits. However, an overlooked aspect of the movement intensity continuum is prolonged sitting or sedentary behavior, and physical inactivity. Thus, this study aimed to conduct a systematic review investigating the associations between sedentary behavior, physical inactivity, and non-motor symptoms, specifically cognitive impairment, depression, and poor sleep in PD. METHODS: Conforming to PRISMA guidelines, a systematic search of the literature was conducted via electronic databases including MEDLINE, CINAHL, Scopus, PubMed and PsycINFO up to February 28, 2023. Studies were included if they investigated associations between sedentary behavior or physical inactivity and at least one non-motor symptom such as depression, poor sleep, and/or cognitive impairment, in adults aged 18 years or older with PD. Quality assessment of the studies was performed using the Newcastle-Ottawa scale for cross-sectional and cohort studies. RESULTS: Of the 463 publications found, 7 studies met the inclusion criteria (n = 980 unique participants). Sample sizes ranged from 17 to 487 participants, and all studies were observational, conducted in home or community settings. Collectively, these studies show that higher amounts of both objectively-measured and self-reported sedentary time are associated with worse scores on standardized measures of cognition and the Parkinson's Disease Questionnaire (PDQ) summary index and its subscales, such as cognition (memory and concentration). Additionally, longitudinal cohort studies suggest that physical inactivity and higher sedentary behavior are associated with depression and cognitive impairment in PD. Less sleep was associated with higher sedentary behavior. CONCLUSION: Associations observed between physical inactivity, sedentary behavior, and non-motor symptoms in PD underscore the need to address these factors for enhanced well-being. Further well-designed studies are essential to assess the impact of reducing sedentary behavior and physical inactivity on non-motor symptoms in PD. Prospero registration number: PROSPERO (ID: CRD42023405422) on April 11, 2023.

The whole day matters after stroke: Study protocol for a randomized controlled trial investigating the effect of a 'sit less, move more, sleep better' program early after stroke.

BACKGROUND: Movement-related behaviours, including prolonged sedentary behaviour, physical inactivity, and poor sleep, are associated with worse functional outcomes poststroke. Addressing these co-dependent behaviours early after stroke may help to optimize recovery and improve overall quality of life for individuals with stroke. OBJECTIVE: This study aims to determine the feasibility and effect of a 'sit less, move more, sleep better' program early after stroke on functional mobility and global disability outcomes, while also exploring imaging and behavioural markers that may influence walking recovery. METHODS: The study is an assessor-blinded, single-center, parallel-group, randomized controlled trial to be completed within 24 months from July 12, 2023 to June 30, 2025. We will enroll 50 patients with acute ischemic stroke within 7 days from symptom onset, aged 18 years or older, and with ongoing walking goals. Demographic and stroke characteristics, including stroke risk factors, neuroimaging, and acute stroke treatments, will be determined and documented. All participants will wear an accelerometer for one week at three different time-points (baseline, 6, and 12 weeks) to assess movement-related behaviours. Following randomization, participants in the intervention arm will receive a 'sit less, move more, sleep better' program for up to 1 hour/day, 5 days/week, for 6 weeks to enhance self-efficacy for change. Participants in the control arm will receive usual inpatient and early supported stroke discharge care. The feasibility outcomes will include reach (enrolled/eligible), retention (completed/enrolled), adverse events, and program adherence. Other outcomes at 6 and 12 weeks include the modified Rankin Scale, Timed-Up and Go, movement-related behaviours, walking endurance, gait speed, cognition, stroke severity and quality of life. Mixed-effects models will assess changes in outcomes over time. Compositional associations between movement-related behaviours and outcomes will consider covariates such as imaging markers. DISCUSSION: Adopting a whole-day approach to poststroke rehabilitation will provide valuable insights into the relationship between optimizing movement-related behaviours early after stroke and their impact on functional outcomes. Through exploring person-specific behavioural and imaging markers, this study may inform precision rehabilitation strategies, and guide clinical decision making for more tailored interventions. TRIAL REGISTRATION: Clinical Trial registration (ClinicalTrials.gov Identifier: NCT05753761, March 3, 2023).

Progressive Resistance Training Program Characteristics in Rehabilitation Programs Following Hip Fracture: A Meta-Analysis and Meta-Regression.

Introduction: Older adults often experience incomplete recovery after a hip fracture. Rehabilitation programs with progressive resistance training are associated with improved functional recovery. This systematic review and meta-analysis with meta-regression a) evaluated resistance training characteristics reported in hip fracture rehabilitation programs, b) performed meta-analysis of resistance training impact on strength (primary outcome), gait and physical activity (secondary outcomes), and c) explored resistance training program characteristics associated with improved outcomes using meta-regression. Materials and Methods: Medline, EMBASE, CINAHLPLUS, and Web of Science Core Collection databases were searched (January2000-February2021). Randomized controlled trials including progressive resistance training rehabilitation programs after hip fracture surgery in adults ≥50 years old were included. Meta-analyses and exploratory meta-regression were performed. Results: Meta-analysis showed significant increases in strength (10 trials-728 participants; Standardized Mean Difference (SMD) [95%CI]; .40 [.02, .78]) immediately following program completion in intervention relative to control participants. Meta-analysis on 5 trials (n = 384) with extended follow up found no significant group differences (SMD = .47 [-.28, 1.23]) in strength. Center-based relative to home-based programs were associated with significantly greater improvements in strength (P < .05) as were programs where resistance training intensity was prescribed using one-repetition maximum relative to other exercise prescription methods (P < .05). In gait meta-analysis (n = 10 trials-704 participants), gait speed in intervention participants immediately after the program was significantly higher than control (SMD = .42 [.08, .76]) but this finding was not maintained in extended follow-up (n = 5 trials-240 participants; SMD = .6 [-.26, .38]). Higher resistance training intensity was associated with significant improvements in gait speed (P < .05). No meta-analysis was performed for the 3 heterogeneous studies reporting physical activity. Discussion: Progressive resistance training improved muscle strength and gait speed after hip fracture surgery in adults ≥50years old immediately after the program ended, but the longer-term impact may be more limited. Conclusions: Higher resistance training intensity and center-based programs may be associated with more improvement, but require further research.

Development of a predictive algorithm to identify pre-school children at risk for behavior changes associated with sleep-related breathing disorders.

STUDY OBJECTIVES: Children with late-onset (2-5 years) or persistent (3 months-5 years) sleep-related breathing disorder (SRBD) have an increased risk of behavior problems compared to children with no or early-onset SRBD. We sought to determine whether a combination of urine metabolites and sleep questionnaires could identify children at risk for SRBD-associated behavior problems. METHODS: Urine and data were analyzed from the Edmonton site of the CHILD birth cohort study. We measured urine metabolites (random, mid-stream) at age three-years among a sub-cohort of participants (n = 165). Random Forest with a Boruta wrapper was used to identify important metabolites (creatinine-corrected, z-scores) for late/persistent SRBD versus no/early SRBD (reference). An algorithm was subsequently generated to predict late/persistent SRBD in children with a history of snoring using a metabolite composite score (z-scores < or ≥ 0) plus the SDBeasy score defined as [age (yrs.) of most recent positive SRBD]2 - [age (yrs.) first reported ever snoring]2. RESULTS: Of the 165 children with SRBD data, 40 participants had late/persistent SRBD. Seven urinary metabolites in addition to the SDBeasy score were confirmed as important for late/persistent SRBD (AUC = 0.87). Among children with an ever-snoring history and a metabolite composite score ≥0, those with SDBeasy score ≥3 were over 13-fold more likely to have late/persistent SRBD (OR 13.7; 95%CI: 3.0, 62.1; p = 0.001). This algorithm has a Sensitivity of 69.6%, Specificity of 85.7% and a positive likelihood ratio (+LR) of 4.9. CONCLUSIONS: We developed a predictive algorithm using a combination of questionnaires and urine metabolites at age three-years to identify children with late/persistent SRBD by five-years of age.

Influence of Neighborhood Characteristics and Weather on Movement Behaviors at Age 3 and 5 Years in a Longitudinal Birth Cohort.

BACKGROUND: Movement behaviors (physical activity, sedentary time, and sleep) established in early childhood track into adulthood and interact to influence health outcomes. This study examined the associations between neighborhood characteristics and weather with movement behaviors in preschoolers. METHODS: A subset of Canadian Healthy Infant Longitudinal Development birth cohort (n = 385, 50.6% boys) with valid movement behaviors data were enrolled at age 3 years and followed through to age 5 years. Objective measures of neighborhood characteristics were derived by ArcGIS software, and weather variables were derived from the Government of Canada weather website. Random forest and linear mixed models were used to examine predictors of movement behaviors. Cross-sectional analyses were stratified by age and season (winter and nonwinter). RESULTS: Neighborhood safety, temperature, green space, and roads were important neighborhood characteristics for movement behaviors in 3- and 5-year-olds. An increase in temperature was associated with greater light physical activity longitudinally from age 3 to 5 years and also in the winter at age 5 years in stratified analysis. A higher percentage of expressways was associated with less nonwinter moderate to vigorous physical activity at age 3 years. CONCLUSIONS: Future initiatives to promote healthy movement behaviors in the early years should consider age differences, neighborhood characteristics, and season.

Using Intervention Mapping to develop and implement a home-based sedentary behavior change intervention after stroke.

Prolonged sedentary behavior is a problem immediately following a stroke and it persists from the acute to chronic phases of recovery. Frequently interrupting sedentary time might help to mitigate the associated detrimental health consequences. The purpose of this article was to describe the process followed in the systematic development and implementation of a theory- and home-based sedentary behavior change intervention for people with stroke. The Intervention Mapping protocol was used to design, develop and implement a STand Up Frequently From Stroke (STUFFS) program aimed at reducing prolonged sedentary behavior after stroke. A qualitative inquiry with people with stroke (n = 13) informed the development of the intervention. The systematic approach followed in the development process including the theoretical basis, content development, and evaluation planning were described. Program reception was assessed using thematic content analysis of exit-interview data (n = 25). The 8-weeks STUFFS intervention is a home-based sedentary behavior change program that provides education about the risks of prolonged sedentary behavior and facilitates behavior change, including the use of motivational tools to empower people with stroke to reduce sedentary behavior. The program was well-received and acceptable to people with stroke (89% satisfaction). This article provides information that furthers knowledge about theory-based strategies to reduce sedentary behavior in the home environment after stroke and facilitates implementation of this type of intervention. Trial registration: This study is registered at www.clinicaltrials.gov (No. NCT02980744).

The relationship between machine-learning-derived sleep parameters and behavior problems in 3- and 5-year-old children: results from the CHILD Cohort study.

STUDY OBJECTIVES: Machine learning (ML) may provide insights into the underlying sleep stages of accelerometer-assessed sleep duration. We examined associations between ML-sleep patterns and behavior problems among preschool children. METHODS: Children from the CHILD Cohort Edmonton site with actigraphy and behavior data at 3-years (n = 330) and 5-years (n = 304) were included. Parent-reported behavior problems were assessed by the Child Behavior Checklist. The Hidden Markov Model (HMM) classification method was used for ML analysis of the accelerometer sleep period. The average time each participant spent in each HMM-derived sleep state was expressed in hours per day. We analyzed associations between sleep and behavior problems stratified by children with and without sleep-disordered breathing (SDB). RESULTS: Four hidden sleep states were identified at 3 years and six hidden sleep states at 5 years using HMM. The first sleep state identified for both ages (HMM-0) had zero counts (no movement). The remaining hidden states were merged together (HMM-mov). Children spent an average of 8.2 ± 1.2 h/day in HMM-0 and 2.6 ± 0.8 h/day in HMM-mov at 3 years. At age 5, children spent an average of 8.2 ± 0.9 h/day in HMM-0 and 1.9 ± 0.7 h/day in HMM-mov. Among SDB children, each hour in HMM-0 was associated with 0.79-point reduced externalizing behavior problems (95% CI -1.4, -0.12; p < 0.05), and a 1.27-point lower internalizing behavior problems (95% CI -2.02, -0.53; p < 0.01). CONCLUSIONS: ML-sleep states were not associated with behavior problems in the general population of children. Children with SDB who had greater sleep duration without movement had lower behavioral problems. The ML-sleep states require validation with polysomnography.

Sit less and move more: perspectives of adults with multiple sclerosis.

PURPOSE: Multiple sclerosis is a chronic neurological disease with the highest prevalence in Canada. Replacing sedentary behavior with light activities may be a feasible approach to manage multiple sclerosis symptoms. This study explored the perspectives of adults with multiple sclerosis about sedentary behavior, physical activity and ways to change behavior. METHODS: Fifteen adults with multiple sclerosis (age 43 ± 13 years; mean ± standard deviation), recruited through the multiple sclerosis Clinic at the University of Alberta, Edmonton, Canada, participated in semi-structured interviews. Interview audios were transcribed verbatim and coded. NVivo software was used to facilitate the inductive process of thematic analysis. RESULTS: Balancing competing priorities between sitting and moving was the primary theme. Participants were aware of the benefits of physical activity to their overall health, and in the management of fatigue and muscle stiffness. Due to fatigue, they often chose sitting to get their energy back. Further, some barriers included perceived fear of losing balance or embarrassment while walking. Activity monitoring, accountability, educational and individualized programs were suggested strategies to motivate more movement. CONCLUSIONS: Adults with multiple sclerosis were open to the idea of replacing sitting with light activities. Motivational and educational programs are required to help them to change sedentary behavior to moving more. IMPLICATIONS FOR REHABILITATION One of the most challenging and common difficulties of multiple sclerosis is walking impairment that worsens because of multiple sclerosis progression, and is a common goal in the rehabilitation of people with multiple sclerosis. The deterioration in walking abilities is related to lower levels of physical activity and more sedentary behavior, such that adults with multiple sclerosis spend 8 to 10.5 h per day sitting. Replacing prolonged sedentary behavior with light physical activities, and incorporating education, encouragement, and self-monitoring strategies are feasible approaches to manage the symptoms of multiple sclerosis.

Physical activity, sedentary behavior, and long-term cardiovascular risk in individuals with rheumatoid arthritis.

Objective: Individuals with rheumatoid arthritis (RA) have increased risk of cardiovascular disease (CVD). Lifestyle factors such as prolonged sedentary behavior (SB) and reduced physical activity (PA) may heighten the risk of CVD. The objective of the study was to investigate the role of SB and PA as predictors for long-term CVD risk in RA patients.Methods: A subsample of 273 people diagnosed with RA was extracted from the 2003-2006 National Health and Nutrition Examination Survey and included in this cross-sectional study. Valid accelerometry data were categorized into sedentary behavior, very light, light, and moderate-to-vigorous physical activity. Functional limitations were assessed using a physical function questionnaire. The Framingham risk score (FRS) was used to calculate 10-year CVD risk. Regression models were used to examine the relationships between SB, PA, and 10-year CVD risk while controlling for potential confounders.Results: Participants spent an average of 9 h/day sedentary, 4 h in very light PA, 1 h in light PA, and 0.4 h in moderate-to-vigorous PA. Greater sedentary time was associated with higher 10-year CVD risk (p= 0.019). Increased daily PA, at all intensities, was inversely associated with 10-year CVD risk (p< 0.01). In the fully adjusted regression model, associations between 10-year CVD risk and SB (ß = 0.31, R2 = 0.27, p< 0.01), very light PA (ß = -0.19, R2 = 0.26, p< 0.01), light PA (ß = -0.16, R2 = 0.25, p< 0.01), and moderate-to-vigorous PA (ß = -0.15, R2 = 0.25, p< 0.01) remained significant.Conclusions: Strategies for decreasing SB and increasing PA should be explored with individuals with RA in order to decrease long-term CVD risk.

Associations between meeting the Canadian 24-Hour Movement Guidelines for the Early Years and behavioral and emotional problems among 3-year-olds.

OBJECTIVES: Primary: examine associations between meeting the 24-Hour Movement Guidelines for the Early Years and behavioral and emotional problems in a large sample of 3-year-old children. Secondary: determine the proportion of children meeting the Canadian 24-Hour Movement Guidelines. DESIGN: Cross-sectional. METHODS: Participants were 3-year olds (n=539) from the Edmonton site of the Canadian Healthy Infant Longitudinal Development (CHILD) birth cohort. Physical activity and sleep duration were accelerometer-derived while screen time was parent-reported. Meeting the overall guidelines was defined as: (1) ≥180min/day of total physical activity, including 60min/day of moderate- to vigorous-intensity physical activity, (2) ≤1h/day of screen time, and (3) 10-13h of sleep per 24-hour period. Externalizing, internalizing, and total problem scores (lower scores representing fewer problems) were calculated from the parent-reported Child Behavior Checklist (CBCL). Descriptive statistics and linear regression models were completed. RESULTS: Only 5% of children met the overall guidelines (all three recommendations), with 19.3%, 50.5%, and 83.1% meeting the physical activity, screen time, and sleep recommendations, respectively. Meeting more recommendations was associated with lower scores for total (B=-1.78, 95%CI: -3.03, -0.54), externalizing (B=-1.51, 95%CI: -2.80, -0.22) and internalizing (B=-1.35, 95%CI: -2.60, -0.01) problems. Similar findings were also observed for the specific combinations of: (1) physical activity and screen time and (2) sleep duration and screen time. CONCLUSIONS: Meeting more recommendations within the 24-hour Movement Guidelines was associated with fewer behavioral and emotional problems at 3-years. Few 3-year-olds met the overall guidelines. Findings support an integrated approach for healthy growth and development.

Screen-time is associated with inattention problems in preschoolers: Results from the CHILD birth cohort study.

BACKGROUND: Pre-school children spend an average of two-hours daily using screens. We examined associations between screen-time on pre-school behavior using data from the Canadian Healthy Infant Longitudinal Development (CHILD) study. METHODS: CHILD participant parents completed the Child Behavior Checklist (CBCL) at five-years of age. Parents reported their child's total screen-time including gaming and mobile devices. Screen-time was categorized using the recommended threshold of two-hours/day for five-years or one-hour/day for three-years. Multiple linear regression examined associations between screen-time and externalizing behavior (e.g. inattention and aggression). Multiple logistic regression identified characteristics of children at risk for clinically significant externalizing problems (CBCL T-score≥65). RESULTS: Screen-time was available for over 95% of children (2,322/2,427) with CBCL data. Mean screen-time was 1·4 hours/day (95%CI 1·4, 1·5) at five-years and 1·5 hours/day (95%CI: 1·5, 1·6) at three-years. Compared to children with less than 30-minutes/day screen-time, those watching more than two-hours/day (13·7%) had a 2·2-point increase in externalizing T-score (95%CI: 0·9, 3·5, p≤0·001); a five-fold increased odd for reporting clinically significant externalizing problems (95%CI: 1·0, 25·0, p = 0·05); and were 5·9 times more likely to report clinically significant inattention problems (95%CI: 1·6, 21·5, p = 0·01). Children with a DSM-5 ADHD T-score above the 65 clinical cut-off were considered to have significant ADHD type symptoms (n = 24). Children with more than 2-hours of screen-time/day had a 7·7-fold increased risk of meeting criteria for ADHD (95%CI: 1·6, 38·1, p = 0·01). There was no significant association between screen-time and aggressive behaviors (p>0.05). CONCLUSION: Increased screen-time in pre-school is associated with worse inattention problems.

Identifying factors associated with sedentary time after stroke. Secondary analysis of pooled data from nine primary studies.

Background: High levels of sedentary time increases the risk of cardiovascular disease, including recurrent stroke. Objective: This study aimed to identify factors associated with high sedentary time in community-dwelling people with stroke. Methods: For this data pooling study, authors of published and ongoing trials that collected sedentary time data, using the activPAL monitor, in community-dwelling people with stroke were invited to contribute their raw data. The data was reprocessed, algorithms were created to identify sleep-wake time and determine the percentage of waking hours spent sedentary. We explored demographic and stroke-related factors associated with total sedentary time and time in uninterrupted sedentary bouts using unique, both univariable and multivariable, regression analyses. Results: The 274 included participants were from Australia, Canada, and the United Kingdom, and spent, on average, 69% (SD 12.4) of their waking hours sedentary. Of the demographic and stroke-related factors, slower walking speeds were significantly and independently associated with a higher percentage of waking hours spent sedentary (p = 0.001) and uninterrupted sedentary bouts of >30 and >60 min (p = 0.001 and p = 0.004, respectively). Regression models explained 11-19% of the variance in total sedentary time and time in prolonged sedentary bouts. Conclusion: We found that variability in sedentary time of people with stroke was largely unaccounted for by demographic and stroke-related variables. Behavioral and environmental factors are likely to play an important role in sedentary behavior after stroke. Further work is required to develop and test effective interventions to address sedentary behavior after stroke.

Relationships between sedentary behaviour, physical activity levels and red blood cell distribution width in children and adolescents.

Background: Red blood cell distribution width (RDW) is a biomarker for cardiovascular disease(CVD). RDW is associated with sedentary behavior (SB) and physical activity (PA) in adults.To date, no study has evaluated this association in children. The purpose of this study was to evaluate the association between RDW and SB and PA levels of children and adolescents. Methods: This observational study included data from participants aged 12-20 years in the 2003-2006 National Health and Nutrition Examination Survey (NHANES). SB and PA were measured using accelerometers. Activity levels were classified into intensity categories. Sex specific multivariable regression analyses (adjusted for covariates) were used to explore the associations between SB, PA and RDW. Results: The study included 2143 children and adolescents (1080 boys and 1063 girls). In the fully adjusted regression model for boys, SB was positively associated with RDW (ß =0.116,P=0.004) while moderate PA was negatively associated with RDW (ß =-0.082, P=0.048). In girls, there were no significant associations between activity levels and RDW. Conclusion: This study provides preliminary evidence of the association between SB, moderate intensity PA and RDW in boys, but not in girls. Further research to determine the mechanisms associated with this relationship and underlying sex differences is warranted.

Reducing sedentary behaviour after stroke: perspectives of ambulatory individuals with stroke.

PURPOSE: Understanding the determinants of sedentary behaviour (sitting or lying with low energy expenditure) in stroke survivors can enhance the development of successful behaviour change strategies. This qualitative study explored the perceptions of stroke survivors about sedentary behaviour and ways in which it can be changed. METHODS: An interpretative qualitative inquiry was used with thematic analysis of interview data. Interviews were conducted using a semi-structured guide with 13 stroke survivors. Interview transcripts were analysed using thematic analysis. Self-reported sedentary time was assessed during interviews. RESULTS: Four main themes emerged from the data: meaning of sedentary behaviour, reasons for sedentary behaviour, barriers and facilitators to reducing sedentary behaviour, and strategies to sit less and move more. Only 6 participants knew about sedentary behaviour, and 2 were aware of the associated health risks. Participants encountered barriers in their daily lives that affect engagement in activity including motor impairments, fatigue, cognitive problems, and lack of motivation. Using wearable technologies and action planning to reduce sedentary behaviour hold promise as behaviour change strategies. CONCLUSIONS: There is limited awareness of health risks of sedentary behaviour among stroke survivors. Strategies involving self-monitoring and movement throughout the day are potential ways to reduce sedentary behaviour. Implications for Rehabilitation Reducing sedentary behaviour in ambulatory stroke survivors is dependent on a number of modifiable determinants. Planning regular interruptions in sedentary time, such as standing or walking frequently throughout waking hours, during television commercial breaks or while using the phone are some potential strategies for reducing sedentary behaviour in stroke survivors. Availability of social and professional support and self-monitoring using wearable technologies that provide real-time feedback might result in increased motivation to sit less and move more. Using alarms and devices that provide cues to action by reminding participants to sit less and move more were perceived as important.

Mobility disability and the pattern of accelerometer-derived sedentary and physical activity behaviors in people with multiple sclerosis.

OBJECTIVE: Low physical activity and high sedentary behavior levels are major concerns in persons with multiple sclerosis (MS) and these differ depending on the level of mobility disability. However, the manner in which daily activity is accumulated is currently unknown in this population. METHODS: A secondary analysis was performed on a combined data set of persons with MS from two previous investigations of physical activity and symptomatic or quality of life outcomes in the United States over a two year period (2007-2009). Mobility disability status was determined using the Patient Determined Disease Steps (PDDS) while activity behavior was objectively monitored using an ActiGraph accelerometer for 7 days. RESULTS: Persons with MS who have mobility disability were involved in sedentary behavior, light and moderate intensity activity for 65%, 34% and 1% of the day, respectively compared to 60%, 37%, and 3%, respectively in those without mobility disability (p < 0.05). Breaks in sedentary time did not differ by mobility disability status. Compared to those without mobility disability, the average number of sedentary bouts longer than 30 min was greater in those with mobility disability (p = 0.016). CONCLUSION: Persons with MS with mobility disability are less active, engage in more sedentary behavior and accumulate prolonged sedentary bouts.

Accelerometer-Derived Pattern of Sedentary and Physical Activity Time in Persons with Mobility Disability: National Health and Nutrition Examination Survey 2003 to 2006.

OBJECTIVES: To describe objectively determined sedentary and activity outcomes (volume and pattern) and their associations with cardiometabolic risk biomarkers in individuals with and without mobility disability. DESIGN: Cross-sectional. SETTING: Population based. PARTICIPANTS: Community-dwelling older adults (≥60) living in the United States who were participants in the 2003 to 2004 or 2005 to 2006 National Health and Nutrition Examination Survey. Participants were classified as with or without mobility disability according to responses to self-reported questions about ability to walk, climb stairs, and/or use of ambulatory aids. MEASUREMENTS: Accelerometer-derived sedentary and activity variables for volume (time in sedentary (<100 counts per minute (cpm)), very light- (100-759 cpm), light- (760-1,951 cpm), and moderate- to vigorous- (≥1,952 cpm) intensity activity and pattern (number of breaks from sedentary time, duration of sedentary bouts, duration of activity bouts). Survey-weighted regression models, adjusted for age, sex, ethnicity, education, and smoking, were used to examine the associations between pattern of activity and cardiometabolic health risk factors (blood pressure, waist circumference, high-density lipoprotein cholesterol). RESULTS: Of the 2,017 participants, 547 were classified as having a mobility disability. Participants with mobility disability had more sedentary time and less active time than those without. Sedentary bouts were longer and active bouts shorter in those with disability. The total number of sedentary breaks (transitions from sedentary to nonsedentary) differed between groups after adjustment for total sedentary time. Fewer breaks, longer sedentary bouts, and shorter activity bouts were associated with higher average waist circumference regardless of disability status. CONCLUSION: This study provides rationale for the development and testing of interventions to change the pattern of activity (e.g., include more breaks and longer activity bout durations) in older adults with mobility disability.