7-day Accelerometer Research Articles

Physical Activity Levels, Cardiorespiratory Fitness, and Physical Literacy in Children With a Chronic Medical Condition.

This study investigated differences in cardiorespiratory fitness (CRF) and other physical literacy domains between children with a chronic medical condition (CMC) who adhered to with the physical activity guideline and those who did not. Forty children with a CMC (7-12years) wore an accelerometer for 7days to measure moderate-to-vigorous physical activity. CRF and muscle power were assessed with a maximal cardiopulmonary exercise test, and motor performance was measured with an exercise course. Motivation, confidence, knowledge, and understanding were assessed with a questionnaire. Children who adhered to the PA guideline (n =13) scored significantly higher for CRF, muscle power, motivation and confidence than children who did not adhere to the PA guideline (n =27). No significant differences were found for motor performance, knowledge and understanding. Future research should investigate the effect of paying specific attention to motivation and confidence in children with a CMC to stimulate their adherence to the PA guideline.

Impact of motivational feedback on levels of physical activity and quality of life by activity monitoring following knee arthroplasty surgery—protocol for a randomized controlled trial nested in a prospective cohort (Knee-Activity)

BackgroundEvidence on how to improve daily physical activity (PA) levels following total knee arthroplasty (TKA) or medial uni-compartmental knee arthroplasty (mUKA) by motivational feedback is lacking. Moreover, it is unknown whether a focus on increased PA after discharge from the hospital improves rehabilitation, physical function, and quality of life. The aim of this randomized controlled trial (RCT) nested in a prospective cohort is (a) to investigate whether PA, physical function, and quality of life following knee replacement can be increased using an activity monitoring device including motivational feedback via a patient app in comparison with activity monitoring without feedback (care-as-usual), and (b) to investigate the potential predictive value of PA level prior to knee replacement for the length of stay, return to work, and quality of life.MethodsThe study is designed as a multicenter, parallel-group, superiority RCT with balanced randomization (1:1) and blinded outcome assessments. One hundred and fifty patients scheduled for knee replacement (TKA or mUKA) will be recruited through Odense University Hospital, Denmark, Vejle Hospital, Denmark and Herlev/Gentofte Sygehus, Denmark. Patients will be randomized to either 12 weeks of activity monitoring and motivational feedback via a patient app by gamification or 'care-as-usual,' including activity monitoring without motivational feedback. The primary outcome is the between-group change score from baseline to 12-week follow-up of cumulative daily accelerometer counts, which is a valid proxy for average objectively assessed daily PA.DiscussionImproving PA through motivational feedback following knee replacement surgery might improve post-surgical function, health-related quality of life, and participation in everyday life.Trial registrationClinicalTrials.gov, ID: NCT06005623. Registered on 2023–08-22.Trial statusRecruiting.

Association of Recess Provision With Accelerometer-Measured Physical Activity and Sedentary Time in a Representative Sample of 6- to 11-Year-Old Children in the United States.

To assess the association between the amount of recess provision and children's accelerometer-measured physical activity (PA) levels. Parents/guardians of 6- to 11-year-olds (n = 451) in the 2012 National Youth Fitness Survey reported recess provision, categorized as low (10-15min; 31.9%), medium (16-30min; 48.0%), or high (>30min; 20.1%). Children wore a wrist-worn accelerometer for 7days to estimate time spent sedentary, in light PA, and in moderate to vigorous PA using 2 different cut points for either activity counts or raw acceleration. Outcomes were compared between levels of recess provision while adjusting for covariates and the survey's multistage, probability sampling design. Children with high recess provision spent less time sedentary, irrespective of type of day (week vs weekend) and engaged in more light or moderate to vigorous PA on weekdays than those with low recess provision. The magnitude and statistical significance of effects differed based on the cut points used to classify PA (eg,4.7 vs 11.9 additional min·d-1 of moderate to vigorous PA). Providing children with >30minutes of daily recess, which exceeds current recommendations of ≥20minutes, is associated with more favorable PA levels and not just on school days. Identifying the optimal method for analyzing wrist-worn accelerometer data could clarify the magnitude of this effect.

Free-living ambulatory physical activity and cognitive function in multiple sclerosis: the significance of step rate vs. step volume.

Physical activity (PA) represents a promising behavioral approach for managing cognitive dysfunction in multiple sclerosis (MS). However, there is a lack of information on the pattern of free-living PA intensity (e.g., step rate) and its unique association with cognition. Such information is essential for informing clinical trials in MS. We examined associations among PA volume and intensity with cognitive function in persons with MS, and intensity was derived from steps-based metrics (peak 30-min cadence [Peak-30CAD], and time spent in incremental cadence bands). We included data from 147 persons with MS who underwent assessments of cognitive function (via Brief International Cognitive Assessment in MS) and wore an ActiGraph GT3X + accelerometer for 7days. We performed bivariate and partial correlations and regression analyses examining associations among PA metrics and cognitive outcomes. Higher Peak-30CAD was significantly associated with better performance in cognitive processing speed and verbal learning and memory (rs = 0.19-0.38), and the associations remained significant when controlling for daily steps, age, sex, and years of education (p < 0.05). By comparison, daily steps was only correlated with cognitive processing speed (rs = 0.26), and the association was non-significant when controlling for Peak-30CAD and covariates. There were stronger correlations among time spent in higher intensity cadence bands with cognitive performance (rs = 0.18-0.38). Our results highlight the important role of PA intensity for cognition in MS, and may inform future development of focal PA interventions that focusing on step rate patterns for improving cognition in persons with MS.

Exploring Associations Between Device-Based Occupational Sedentary Behavior and Need for Recovery in White Collar Workers: A Compositional Data-Analysis.

White collar workers spend an increasing amount of time in occupational sedentary behavior (OSB) and are thereby at risk for adverse health outcomes. Nevertheless, the association between OSB and the need for recovery (NFR), an important indicator of wellbeing, is unknown and therefore examined. Baseline data from a cluster randomized controlled trial was used. A subgroup of 89 white collar workers wore a triaxial accelerometer for 7days. NFR was measured using the Questionnaire on the Experience and Evaluation of Work. Compositional data analysis was applied to determine the composition of different OSB bouts (short, medium and long) and occupational physical activity (OPA) (light, moderate and vigorous and standing). Linear regression analyses were performed to explore the associations between occupational compositions and NFR. Relatively more time spent in long OSB bouts was associated with a lower NFR (β: -11.30, 95% CI: -20.2 to -2.4). Short and medium OSB bouts and OPA were not associated with NFR. Associations between OSB bouts, OPA and NFR hinted at contrasting trends, suggesting the need to consider different bout lengths of OSB in future studies.

Movement Patterns in Older Adults Recovering From Hip Fracture.

The aim of this study was to quantify physical activity and sedentary behavior in older adults recovering from hip fracture and to identify groups based on movement patterns. In this cross-sectional cohort study, older adults (≥70years) were included 3 months after surgery for proximal femoral fracture. Patients received an accelerometer for 7days. Demographics and outcomes related to physical function, mobility, cognitive functions, quality of life, and hip fracture were assessed. In total, 43 patients with sufficient accelerometer wear time were included. Across all groups, participants engaged in very low levels of physical activity, spending an average of 11hr/day in prolonged sedentary behavior. Based on the extracted components from a principal component analysis, three groups with substantial differences in levels of physical activity and sedentary behavior could be distinguished.

Associations between actigraphy-measured sleep duration, continuity, and timing with mortality in the UK Biobank.

To examine the associations between sleep duration, continuity, timing, and mortality using actigraphy among adults. Data were from a cohort of 88 282 adults (40-69 years) in UK Biobank that wore a wrist-worn triaxial accelerometer for 7 days. Actigraphy data were processed to generate estimates of sleep duration and other sleep characteristics including wake after sleep onset (WASO), number of 5-minute awakenings, and midpoint for sleep onset/wake-up and the least active 5 hours (L5). Data were linked to mortality outcomes with follow-up to October 31, 2021. We implemented Cox models (hazard ratio, confidence intervals [HR, 95% CI]) to quantify sleep associations with mortality. Models were adjusted for demographics, lifestyle factors, and medical conditions. Over an average of 6.8 years 2973 deaths occurred (1700 cancer, 586 CVD deaths). Overall sleep duration was significantly associated with risk for all-cause (p < 0.01), cancer (p < 0.01), and CVD (p = 0.03) mortality. For example, when compared to sleep durations of 7.0 hrs/d, durations of 5 hrs/d were associated with a 29% higher risk for all-cause mortality (HR: 1.29 [1.09, 1.52]). WASO and number of awakenings were not associated with mortality. Individuals with L5 early or late midpoints (<2:30 or ≥ 3:30) had a ~20% higher risk for all-cause mortality, compared to those with intermediate L5 midpoints (3:00-3:29; p ≤ 0.01; e.g. HR ≥ 3:30: 1.19 [1.07, 1.32]). Shorter sleep duration and both early and late sleep timing were associated with a higher mortality risk. These findings reinforce the importance of public health efforts to promote healthy sleep patterns in adults.

Using Accelerometer Data to Identify Physical Activity Profiles in the Osteoarthritis Initiative

Introduction: Osteoarthritis is a chronic joint disease with no current cure, affecting around 500 million people worldwide. Evidence suggests that physical activity has beneficial effects, but the ideal “prescription” of exercise remains unknown. The Osteoarthritis Initiative is a longitudinal, prospective, observational study with over 10 years of follow-up with accelerometer data from 2712 subjects. In this project, we used a data-driven approach to identify physical activity patterns based on daily accelerometer information. Using these patterns, we established profiles and determined if associations exist between the created profiles and known correlates and symptomatic outcomes of osteoarthritis such as pain.&#x0D; Methods: Physical activity curves for subjects with accelerometer data from the Osteoarthritis Initiative were aligned using curve registration methods. Once curves were aligned, subjects were grouped into profiles using k-medoid clustering. The outcome of pain was measured by the total Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score. A linear regression model was used to determine if an association exists between the defined profiles and the total WOMAC score.&#x0D; Results: K-medoid clustering of physical activity curves resulted in two profiles. However, there was no association between the defined profiles and the total WOMAC score at the alpha level of 0.05.&#x0D; Discussion: The developed profiles are not associated with the total WOMAC score. While the created profiles are not associated with symptomatic outcomes, it is of interest to explore if they provide prediction abilities for structural outcomes such as joint space width and radiographic classification of osteoarthritis such as the Kellgren-Lawrence score.

Associations between patterns of physical activity, pain intensity, and interference among older adults with chronic pain: a secondary analysis of two randomized controlled trials.

Background: Clinical management of chronic pain often includes recommendations to engage in physical activity (PA), though there are little data on the interplay between pain symptoms and key aspects of PA participation (e.g., intensity and bout duration) among older adults. Herein we investigate the longitudinal relationships between changes in PA behavior and changes in pain intensity and interference among low-active older adults with obesity and chronic pain. Methods: Participants (N = 41) were enrolled in two randomized pilot trials wherein they were assigned to an intervention focused on participation in frequent PA across the day, or to a low-contact control. Participants completed the 3-item PROMIS pain intensity scale and 8-item PROMIS pain interference scale before and after the interventions. Participants also wore an ActivPAL accelerometer for 7days before and during the final week of the interventions. Results: A series of linear regression analyses demonstrated that increased time spent stepping at a high-light intensity in very short bouts was associated with increased pain intensity scores. By contrast, increased time spent stepping at a high-light intensity in bouts of 5-20min was associated with reductions in pain intensity and interference scores. Increased time spent stepping at a moderate intensity overall was associated with reduced pain intensity scores, and time spent stepping at a moderate intensity for 10-20min associated with reduced pain interference. Conclusion: These findings suggest older adults with chronic pain may benefit by moving at high-light or moderate intensities in brief bouts of at least 5min in duration.

Associations Between Changes in Activity and Dietary Behaviors after Metabolic and Bariatric Surgery.

Patients who undergo metabolic and bariatric surgery (MBS) are advised to make healthy activity and dietary changes. While previous research has examined post-surgical changes in activity and dietary behaviors separately, no study has assessed whether changes in these behaviors are beneficially associated with each other. We evaluated whether post-surgical improvements in activity behaviors related to favorable changes in dietary behaviors overall and by surgery type (Roux-en-Y gastric bypass [RYGB], sleeve gastrectomy [SG]). At pre-surgery and 6- and 12-months post-surgery, participants (N = 97; 67 RYGB/30 SG) wore an accelerometer for 7days and completed 24-h dietary assessments on 3days. General linear models assessed associations between pre- to post-surgical changes in activity (moderate-to-vigorous physical intensity activity [MVPA], sedentary time [ST]) and dietary (total energy intake [EI; kcal/day], dietary quality [healthy eating index/HEI scores]) behaviors, with surgery type as a moderator. Participants on average: demonstrated small, non-significant post-surgical changes in MVPA and ST minutes/day (ps > .05); and reported significant post-surgical decreases in EI (p < .001), but no changes in HEI scores (ps > .25). Greater 12-month post-surgical increases in MVPA were significantly associated with greater decreases in EI, but only for RYGB participants (p < .001). Participants reported large decreases in EI, but made minimal changes in other behaviors after MBS. Results suggest greater increases in MVPA could assist with achieving greater decreases in EI, although this benefit appears to be limited to RYGB patients. Additional research is needed to confirm these findings and determine whether activity-dietary behavior associations differ beyond the immediate post-surgical year.

Leave the screen: The influence of everyday behaviors on self-reported interoception

The influence of physical activity on interoception is apparent, however little is known about within-person variability following physical activity and sedentary behavior in daily life. To test this, 70 healthy adults (Mage 21.67 ± 2.50) wore thigh-mounted accelerometers for 7-days, with self-reported interoception recorded on movement-triggered smartphones. Participants additionally reported the predominant activity type performed across the last 15 min. Investigating this timeframe, multi-level analyses revealed that each one-unit increase in physical activity was associated with an increase in self-reported interoception (B = 0.0025, p = .013), whereas contrastingly, each one-minute increase in sedentary behavior was associated with a decrease (B = −0.06. p = .009). Investigating the influence of different activity types in comparison to screen time behavior, both partaking in exercise (B = 4.48, p < .001) and daily-life physical activity (B = 1.21, p < .001) were associated with an increase in self-reported interoception. Regarding other behavior categories, non-screen time behavior both with (B = 1.13, p < .001) and without (B = 0.67, p = .004) social interaction were also associated with an increase in self-reported interoception compared to screen-time behavior. Extending from previous laboratory-based studies, these findings indicate that physical activity influences interoceptive processes in real-life, further supplemented by the novel and contrasting findings regarding sedentary behavior. Furthermore, associations with activity type reveal important mechanistic information, highlighting the importance of reducing screen-time behavior to preserve and support interoceptive perceptions. Findings can be used to inform health recommendations for reducing screen-time behavior and guiding evidence-based physical activity interventions to promote interoceptive processes.

Analysis of the 24-h activity cycle: An illustration examining the association with cognitive function in the Adult Changes in Thought study.

The 24-h activity cycle (24HAC) is a new paradigm for studying activity behaviors in relation to health outcomes. This approach inherently captures the interrelatedness of the daily time spent in physical activity (PA), sedentary behavior (SB), and sleep. We describe three popular approaches for modeling outcome associations with the 24HAC exposure. We apply these approaches to assess an association with a cognitive outcome in a cohort of older adults, discuss statistical challenges, and provide guidance on interpretation and selecting an appropriate approach. We compare the use of the isotemporal substitution model (ISM), compositional data analysis (CoDA), and latent profile analysis (LPA) to analyze 24HAC. We illustrate each method by exploring cross-sectional associations with cognition in 1,034 older adults (Mean age = 77; Age range = 65-100; 55.8% female; 90% White) who were part of the Adult Changes in Thought (ACT) Activity Monitoring (ACT-AM) sub-study. PA and SB were assessed with thigh-worn activPAL accelerometers for 7-days. For each method, we fit a multivariable regression model to examine the cross-sectional association between the 24HAC and Cognitive Abilities Screening Instrument item response theory (CASI-IRT) score, adjusting for baseline characteristics. We highlight differences in assumptions and the scientific questions addressable by each approach. ISM is easiest to apply and interpret; however, the typical ISM assumes a linear association. CoDA uses an isometric log-ratio transformation to directly model the compositional exposure but can be more challenging to apply and interpret. LPA can serve as an exploratory analysis tool to classify individuals into groups with similar time-use patterns. Inference on associations of latent profiles with health outcomes need to account for the uncertainty of the LPA classifications, which is often ignored. Analyses using the three methods did not suggest that less time spent on SB and more in PA was associated with better cognitive function. The three standard analytical approaches for 24HAC each have advantages and limitations, and selection of the most appropriate method should be guided by the scientific questions of interest and applicability of each model's assumptions. Further research is needed into the health implications of the distinct 24HAC patterns identified in this cohort.

Association Between Frailty and Free-Living Walking Performance in People With Multiple Sclerosis.

The purpose of this study was to examine the association between frailty and the quantity and quality of free-living walking and the mediating effect of frailty on the relationship between disability and walking performance in people with multiple sclerosis (MS). Ninety-nine people with relapsing-remitting MS (mean age = 49.3 [SD = 9.8] years; 73.7% women; Expanded Disability Status Scale [EDSS] score range = 2.0-6.0) wore a triaxial accelerometer for 7days. Recorded measures reflected the quantity (daily step counts, number of 30-second walking bouts, and signal vector magnitude [SVM]) and quality (gait speed, step cadence, step and stride regularity, and sample entropy) of walking. For each walking quality measure, the typical (median), best (90th percentile), and worst (10th percentile) values were calculated. Frailty was evaluated through a 38-item frailty index. Participants were classified as not frail (n = 31), moderately frail (n = 34), and severely frail (n = 34) on the basis of established procedures. Patients who were moderately and severely frail exhibited poorer performance in all measures of walking quantity and quality, except for sample entropy, than individuals who were not frail. No differences in free-living walking performance were observed between the moderately and severely frail groups. Frailty did not mediate the relationship between disability (EDSS) and measures of walking quality. Conversely, frailty had a significant mediating effect on the relationship between disability and measures of walking quantity, such as daily step counts (indirect effect: b = -220.42, 95% CI = -452.03 to -19.65) and SVM (indirect effect: b = -1.00, 95% CI = -1.86 to -0.30). Frailty is associated with poorer free-living walking performance in people with MS. The study findings suggest that frailty, rather than disability, may be primarily responsible for the lower amount of physical activity performed by people with MS in the real world. The observation that frailty and disability are differently related to measures of walking quality and quantity underscores the importance of a targeted approach to rehabilitation in people with MS.

Self-reported walking pace: A simple screening tool with lowest risk of all-cause mortality in those that ‘walk the talk’

ABSTRACT To determine whether the association between self-reported walking pace and all-cause mortality (ACM) persists across categories of accelerometer-assessed physical activity status. Data from 93,709 UK Biobank participants were included. Physical activity was assessed using wrist-worn accelerometers for 7-days. Participants accumulating <150 min/week moderate-to-vigorous- activity were classed as “inactive”, ≥150 min/week moderate (≥3 METs) activity as “somewhat active” excluding those with ≥150 min/week upper-moderate-to-vigorous activity (≥4.3 METs), who were classed as “high-active”. Over a 6.3 y (median) follow-up, 2,173 deaths occurred. More than half of slow walkers were “inactive”, but only 26% of steady and 12% of brisk walkers. Associations between walking pace and ACM were consistent with those for activity. “High active” brisk walkers had the lowest risk of ACM (Hazard Ratio (HR) 0.22; 95% CI: 0.17,0.28), relative to “inactive” slow walkers. Within those classed as “inactive”, steady (HR 0.54; 0.46,0.64) and brisk walkers (HR 0.42; 0.34,0.52) had lower risk than slow walkers. In conclusion, self-reported walking pace was associated with accelerometer-assessed physical activity with both exposures having similar associations with ACM. “inactive”, steady, and brisk walkers had lower ACM risk than slow walkers. The pattern was similar for “High active” participants. Overall, “High active” brisk walkers had lowest risk.

Risk and Protective Factors for Frailty in Pre-Frail and Frail Older Adults.

This study aims to evaluate the differences in body composition, physical function, and physical activity between pre-frail/frail older adults and to detect risk and protective factors against frailty and physical frailty. Fried's criteria for frailty and physical frailty using the short-performance physical battery (SPPB) were measured in 179 older participants (75.3 ± 6.4 years old). Body weight, height, and waist, arm, and leg circumferences were obtained as body composition variables. Daily accelerometer outcomes (physical activity and inactivity) were obtained. Pre-frail participants showed overall better physical function and spent more time in physical activity and less time in long inactivity periods than frail participants (p < 0.05). Risk frailty factors were higher waist perimeter (Odds Ratio [OR]: 1.032, 95%CI: 1.003-1.062), low leg performance (OR: 1.025, 95%CI: 1.008-1.043), and inactivity periods longer than 30 min (OR:1.002, 95%CI: 1.000-1.005). Protective factors were standing balance (OR:0.908, 95%CI: 0.831-0.992) and SPPB score (OR: 0.908, 95%CI: 0.831-0.992) for frailty, handgrip strength (OR: 0.902, 95%CI: 0.844-0.964) for physical frailty, and light (OR: 0.986, 95%CI: 0.976-0.996) and moderate-to-vigorous (OR: 0.983, 95%CI: 0.972-0.996) physical activity for both. Our findings suggest that handgrip strength, balance, and physical activity are protective frailty factors and can be monitored in pre-frail older adults. Moreover, poor lower body performance and long inactivity periods are frailty risk factors, which highlights their importance in frailty assessment.

Physical activity changes during an automated online weight loss program.

Evidence-based online behavioral weight loss (BWL) treatment targets a combination of diet, physical activity, and behavioral skills training. While weight loss outcomes are well documented, little is known about changes in physical activity. This study examined changes in objectively measured physical activity across the energy expenditure spectrum during a fully automated, online BWL program. Adults with overweight or obesity (n = 63) completed a 12-week, online BWL program. Participants wore an accelerometer for 7days and body weight was measured in-clinic at pre- and post-treatment. At post-treatment, mean daily moderate-to-vigorous physical activity increased by about 4min (SE = 1.59, p = 0.01). There were no statistically significant changes in light physical activity or time spent sedentary (p's > 0.05). Despite only minimal changes in moderate-to-vigorous physical activity overall, larger increases correlated with greater weight loss (r = - 0.28, p = 0.02), which averaged 6.1% of baseline weight at post-treatment. Though achieving important weight loss outcomes, online programs may fail to produce clinically relevant improvements in physical activity, which can put weight loss maintenance at risk.

Abstract 12390: Accelerometer-Based Digital Measurement of Functional Capacity in Heart Failure Patients

Introduction: Repeated 6MWT in clinic are inconvenient for patients and disruptive to usual clinic throughput. Digital measures may be a means to overcome these challenges and reliably measure functional capacity. Methods: As part of an observational clinical trial (NCT04191356), during an 8-week observation period, patients with heart failure (HF) utilize arm-band biosensors (Biofourmis Everion®) for at least 15 hours daily while carrying out daily activities and complete an in-clinic investigator-guided 6MWT on the first and last days of participation. Interim data (N=30, age 56.17 ± 11.26; 24 males; 3 NYHA I, 25 NYHA II, 2 NYHA III) are used for validation, where the distance of baseline 6MWT is used as reference standard. Results: Passive 6MWT, which is the maximum 6-minute step count derived from daily accelerometer data (Fig 1), is strongly correlated with the reference standard (R=0.7501, P&lt;0.0001, N=30) (Fig 2). Further analysis (Fig 2) reveals that regardless of the duration of the step count, the digital measures consistently have strong correlations with the reference standard, with the highest correlation obtained by Passive 10MWT (R=0.7746, P&lt;0.0001, N=30). Conclusions: Early data highlights that accelerometer data collected during daily activities appears to indicate functional capacity of HF patients. Continued data will validate digital measures against various patient outcomes. Fig 1 Aggregation of Passive 6MWT from step count recorded during daily activities Fig 2 Correlation between accelerometer-derived passive step count digital measures and distance manually measured during baseline investigator-guided 6MWT as reference standard (N=30)

P09-04 Sedentary time measured by GT3X+ accelerometry and its variation with grade level and gender among children and adolescents in Morocco

BackgroundSedentary behavior (SB) in children is related to different health outcomes such as overweight and cardio-metabolic diseases. These negative effects have been widely supported by evidence. However, no data on sedentary time (ST) among Moroccan children has been available, yet. Therefore, the present study examined gender and grade differences in objectively measured sedentary behavior in a sample of Moroccan primary school children and adolescents.MethodsIn total, 172 Moroccan children/adolescents aged between 8 to 14 years old (mean age = 10.92 ± 1.55 years; 49.4% were boys) completed the survey. School grade, gender, height, and weight were collected by questionnaires and ST objectively measured using a tri-axial accelerometer (GTX3+). Study required at least 3 valid weekdays and 1 weekend day with? 600 min/day total wear time. Two-way analysis of covariance and logistic regression analyses, adjusted for BMI z-score and accelerometer wear time, were used to examine gender and grade differences in ST.ResultsMean time spent in SB was 535.93 ± 87.15 min/day or ∼ 62.94% of the average daily accelerometer wear time of 851.45 ±51.35.min/day with statistical differences between weekend and week days (471.357 ± 127.73 minutes/day vs. 559.7661± 90.75 minutes/day; p > 0.001). Adolescents (11-14y) were more involved in sitting tasks when compared to the early grades (8-10y). 550.011±88.827 vs. 521.845±83.602 respectively; p > 0.001.ConclusionST increases between ages 11 and 14 years. On week days children and adolescents spent sitting longer than at weekends. Girls and adolescents were identified as potential risk groups. This report on ST presents valuable information for designing and implementing interventions to decrease time spent in SB among children during class time. Acknowledgements This study was performed with the support of the International Atomic Energy Agency (CRP E4.30.24; RAF 6042).

Physical activity in non-disabled people with early multiple sclerosis: A multicenter cross-sectional study

BackgroundPeople with Multiple Sclerosis (PwMS) show low levels of physical activity (PA), however there has been limited research on PA in early diagnosed and no/minimally impaired (<5 years, EDSS≤ 2.5) PwMS. The aims of the study were to objectively quantify PA levels in non-disabled PwMS, to compare the time spent daily at different PA levels (No activity (NPA), Light PA (LPA), Moderate PA (MPA), and Vigorous PA (VPA)) with healthy subjects (HS), and to examine the association of PA with disability, and clinical measures in PwMS. MethodsWe assessed 58 PwMS (mean age±standard deviation, SD 39.1 ± 10.6years) and 20 HS (mean age±SD 39.3 ± 8.9 years). Demographic and clinical data were recorded at the hospital during the baseline assessment. Subjects wore the wrist GENEActiv accelerometer for 7-days. Data were collected at 100 Hz and summarized into a motor activity (MA) index using 60 s epochs with the following thresholds: MANPA-LPA: 10mG, MALPA-MPA: 100mG, MAMPA-VPA: 350mG. ResultsPwMS show higher NPA and lower VPA compared to matched healthy subjects (NPA: Mean±SD, HS: 7.2 ± 0.9 h/day; PwMS: 8.1 ± 1.2 h/day, p<0.01; VPA: HS: 0.78± 0.42 h/day; PwMS: 0.50± 0.40 h/day, p = 0.01), while no between group differences were observed for LPA and MPA (p>0.05). Bivariate analysis showed that higher NPA was associated with fatigue (Fatigue Severity Scale, FSS score) in PwMS with EDSS 0–1.5 (r = 0.34, p = 0.05). In PwMS with EDSS 2–2.5, NPA was correlated with Six Minute Walk Test (6MWT, r=-0.45, p = 0.02) and CIQ (r=-0.41, p = 0.04), while VPA was more associated with FSS (R= -0.38, p = 0.06). ConclusionThe PA level of PwMS differs from that of healthy subjects even in early diagnosed subjects. In PwMS with EDSS 0–1.5 only, fatigue is associated to prolonged inactive behavior. Conversely, in PwMS with EDSS 2–2.5 both inactivity and vigorous activities are modulated by fatigue, endurance and associated with different level of social participation.

Life satisfaction, health-related quality of life and physical activity after treatment for valvular aortic stenosis.

To investigate health-related quality of life and life satisfaction in children and adolescents treated for isolated congenital valvular aortic stenosis compared to healthy peers. Our second aim was to investigate the relationship between objectively measured physical activity, health-related quality of life and life satisfaction in the same group. Forty-eight patients, 8-18 years of age, were recruited, as well as 43 healthy peers matched for age, gender and residential area. Health-related quality of life was assessed by the KIDSCREEN-52 self-report and parent proxy report, and life satisfaction was evaluated with the Satisfaction With Life Scale. Physical activity was measured with an accelerometer for 7days. Sports participation was self-reported. No differences in the health-related quality of life domains were found between patients and controls in the self-reports. In the proxy reports, parents of the adolescents rated their child's autonomy lower than did the parents of the healthy controls. A negative relationship was found between moderate to vigorous physical activity, sports participation, life satisfaction and the psychological well-being domain in adolescent patients. In children there was a positive relationship between moderate physical activity and the physical and psychological well-being domains. Overall, children and adolescents treated for valvular aortic stenosis reported similar life satisfaction and health-related quality of life as their healthy peers. The negative relationships between intense physical activity and sports participation with health-related quality of life and life satisfaction in adolescent patients might be explained by both physical and psychological factors in these teenagers with complex, lifelong heart disease.