Accelerometer Wear Time Research Articles

A prospective analysis of physical activity and mental health in children: the GECKO Drenthe cohort

BackgroundMental health problems in young people have become a global health burden. The positive effects of physical activity on mental health in adults are well known but still not clear in children. The aim of this study was to investigate to what extent physical activity in early childhood would affect mental health in middle childhood.MethodsFrom the Dutch GECKO Drenthe birth cohort, 850 children (51.5% boys) were enrolled in this analysis. Physical activity and sedentary time were measured at age 5–6 using ActiGraph GT3X. Mental health was assessed using the Strengths and Difficulties Questionnaire (SDQ) at age 5–6 and age 10–11. Multiple linear regression models were used to estimate the associations between physical activity, sedentary time and SDQ subscales, stratified by gender, adjusting for age, BMI, maternal education level, family size, accelerometer wear time and season, and additionally adjusting for SDQ scores at age 5–6 to take tracking of mental health over time into account.ResultsGreater physical activity volume at age 5–6 was associated with lower peer problems scores at age 10–11 in boys and girls. An increase in MVPA was associated with lower peer problems scores in boys (b = -0.445, -0.713 to -0.176) and girls (b = -0.354, -0.601 to -0.107), however, increased sedentary time was linked to higher peer problems scores in boys (b = 1.18, 0.455 to 1.906) and girls (b = 0.870, 0.191 to 1.550). For hyperactivity, higher levels of physical activity volume and MVPA were associated with higher hyperactivity scores in boys. Increased sedentary time was related to lower hyperactivity scores in boys. Further adjustment for SDQ scores at age 5–6 attenuated associations between physical activity and hyperactivity in boys but hardly changed the relationships with peer problems. No significant associations between physical activity and other SDQ subscales or total difficulties scores were observed, neither in boys nor in girls.ConclusionsChildren who are more physically active at age 5–6 have fewer peer problems at age 10–11, and for boys, greater activity levels at age 5–6 could be an indicator of hyperactivity at age 10–11.

Association of Physical Inactivity with MRI Markers of Brain Aging: Assessing Mediation by Cardiometabolic and Epigenetic Factors.

Cardiometabolic risk factors and epigenetic patterns, increased in physically inactive individuals, are associated with an accelerated brain aging process. To determine whether cardiometabolic risk factors and epigenetic patterns mediate the association of physical inactivity with unfavorable brain morphology. We included dementia and stroke free participants from the Framingham Heart Study Third Generation and Offspring cohorts who had accelerometery and brain MRI data (n = 2,507, 53.9% women, mean age 53.9 years). We examined mediation by the 2017-revised Framingham Stroke Risk Profile (FSRP, using weights for age, cardiovascular disease, atrial fibrillation, diabetes and smoking status, antihypertension medications, and systolic blood pressure) and the homeostatic model of insulin resistance (HOMA-IR) in models of the association of physical inactivity with brain aging, adjusting for age, age-squared, sex, accelerometer wear time, cohort, time from exam-to-MRI, and season. We similarly assessed mediation by an epigenetic age-prediction algorithm, GrimAge, in a smaller sample of participants who had DNA methylation data (n = 1,418). FSRP and HOMA-IR explained 8.3-20.5% of associations of higher moderate-to-vigorous physical activity (MVPA), higher steps, and lower sedentary time with higher brain volume. Additionally, FSRP and GrimAge explained 10.3-22.0% of associations of physical inactivity with lower white matter diffusivity and FSRP explained 19.7% of the association of MVPA with lower free water accumulation. Our results suggest that cardiometabolic risk factors and epigenetic patterns partially mediate the associations of physical inactivity with lower brain volume, higher white matter diffusivity, and aggregation of free water in the extracellular compartments of the brain.

The moderating impact of neighborhood walkability on mHealth interventions to increase moderate to vigorous physical activity for insufficiently active adults in a randomized trial

BackgroundEcological models suggest that interventions targeting specific behaviors are most effective when supported by the environment. This study prospectively examined the interactions between neighborhood walkability and an mHealth intervention in a large-scale, adequately powered trial to increase moderate-to-vigorous physical activity (MVPA).MethodsHealthy, insufficiently active adults (N = 512) were recruited purposefully from census block groups ranked on walkability (high/low) and socioeconomic status (SES, high/low). Participants were block-randomized in groups of four to WalkIT Arizona, a 12-month, 2 × 2 factorial trial evaluating adaptive versus static goal setting and immediate versus delayed financial reinforcement delivered via text messages. Participants wore ActiGraph GT9X accelerometers daily for one year. After recruitment, a walkability index was calculated uniquely for every participant using a 500-m street network buffer. Generalized linear mixed-effects hurdle models tested for interactions between walkability, intervention components, and phase (baseline vs. intervention) on: (1) likelihood of any (versus no) MVPA and (2) daily MVPA minutes, after adjusting for accelerometer wear time, neighborhood SES, and calendar month. Neighborhood walkability was probed at 5th, 25th, 50th, 75th, and 95th percentiles to explore the full range of effects.ResultsAdaptive goal setting was more effective in increasing the likelihood of any MVPA and daily MVPA minutes, especially in lower walkable neighborhoods, while the magnitude of intervention effect declined as walkability increased. Immediate reinforcement showed a greater increase in any and daily MVPA compared to delayed reinforcement, especially relatively greater in higher walkable neighborhoods.ConclusionsResults partially supported the synergy hypotheses between neighborhood walkability and PA interventions and suggest the potential of tailoring interventions to individuals’ neighborhood characteristics.Trial RegistrationPreregistered at clinicaltrials.gov (NCT02717663).

Associations Among Physical Activity, Adiposity, and Insulin Resistance in Children Exposed In Utero to Maternal Obesity With and Without Gestational Diabetes.

Investigate whether obesity risk and current weight status are independently associated with physical activity (PA) and whether PA is associated with adiposity and insulin resistance (homeostatic model assessment of insulin resistance) among children with high versus low obesity risk based on in utero exposure to maternal overweight/obesity with gestational diabetes mellitus (GDM; high risk) or without GDM (overweight/obesity; high risk) or maternal normal weight without GDM (low risk). Secondary analysis of data from children born to women with overweight/obesity and GDM, overweight/obesity without GDM, or normal weight without GDM. PA was assessed with accelerometry, percentage of body fat derived from anthropometrics, and homeostatic model assessment of insulin resistance calculated from glucose and insulin. Among 4- to 10-year-old children (N = 163), analyses of covariance showed that children with a current BMI ≥85th percentile had less vigorous PA than those with BMI <85th percentile, but in utero exposure was not an independent predictor of PA. In linear regression modeling, moderate to vigorous PA was inversely associated with percentage of body fat and homeostatic model assessment of insulin resistance independent of age, Tanner stage, and accelerometer wear time, with stronger associations in high-risk groups. Children's PA is related to current weight status but not underlying risk for obesity but may be especially important to reduce obesity and insulin resistance in high-risk children.

Association of Accelerometer-Measured Physical Activity and Sedentary Behavior With Incident Cardiovascular Disease, Myocardial Infarction, and Ischemic Stroke: The Women's Health Study.

Background Few studies have investigated associations of acclerometer-based assessments of physical activity (PA) and sedentary behavior (SB) with incidence of cardiovascular disease (CVD) and its components. This prospective cohort study assessed the associations of accelerometer-measured PA and SB with total CVD, myocardial infarction, and ischemic stroke (IS). Methods and Results The authors included 16 031 women aged 62 years and older, free of CVD, with adherent accelerometer wear (≥10 hours/day for ≥4 days) from the Women's Health Study (mean age, 71.4 years [SD, 5.6 years]). Hip-worn ActiGraph GT3X+ accelerometers measured total volume of PA (total average daily vector magnitude), minutes per day of high-light PA and moderate to vigorous PA (MVPA), and SB. Women reported diagnoses of CVD, which were adjudicated using medical records and death certificates. Hazard ratios (HRs) were estimated for each exposure, and 95% CIsusing Cox proportional hazards models were adjusted for accelerometer wear time, age, self-reported general health, postmenopausal hormone therapy, smoking status, and alcohol use. The hypothetical effect of replacing 10 minutes/day of SB or high-light PA with MVPA on CVD incidence was assessed using adjusted isotemporal substitution Cox models. Over a mean of 7.1 years (SD, 1.6 years) of follow-up, 482 total CVD cases, 107 myocardial infarction cases, and 181 IS cases were diagnosed. Compared with the lowest quartiles of total average daily vector magnitude and MVPA (≤60 minutes), women who were in the highest quartiles (>120 minutes of MVPA) had a 43% (95% CI, 24%-58%) and 38% (95% CI, 18%-54%) lower hazard of total CVD, respectively. Estimates were similar for total average daily vector magnitude and MVPA with IS, but PA was not associated with myocardial infarction overall. High-light PA was not associated with any CVD outcomes. Women who spent <7.4 hours sedentary per day had a 33% (95% CI,11%-49%) lower hazard of total CVD compared with those who spent ≥9.5 hours sedentary. Replacing 10 minutes of SB with MVPA was associated with a 4% lower incidence of total CVD (HR, 0.96 [95% CI, 0.93-0.99]). Conclusions Accelerometer-assessed total PA and MVPA were inversely associated with total CVD and IS incidence, and SB was directly associated with total CVD; high-light PA was not related to CVD.

The association of objectively measured sedentary time with asthma in US youth: A glimpse into the connection between obesity and asthma.

Evidence suggests that asthma and obesity may share a common pathway, possibly through an increase in inflammation. Sedentary time is thought to promote both inflammation and obesity and previous studies have found a relationship between self-reported sedentary and asthma.However, the relationship between objectively measured sedentary time and asthma is not well described. We hypothesized that the association between asthma and sedentary time would not be present when physical activity was measured objectively, nor would objectively-measured sedentary time play an important role in the relationship between asthma and obesity. To determine if there is an association between asthma and objectively measured sedentary time in a large, nationally representative sample of theUnited States youth. Using the National Health and Nutrition Examination Survey 2003-2006, we assessed the relationship between asthma and sedentary time using objectively measured and self-reported measures of sedentary time, in 6-19 years-old subjects with available accelerometry data. We used multivariate logistic regression analysis to determine associations between the risk of asthma and sedentary time controlling for accelerometer wear time, gender, age, race/ethnicity, body mass index percentile, and moderate-to-vigorous physical activity (MVPA). In this cohort, youth with asthma self-reported more time in sedentary behavior, specifically computer time, than those without asthma (p = 0.01). However, when sedentary time was measured objectively by accelerometry, sedentary time did not differ between youth with and without asthma (421 min [standard deviation 4.2] versus. 414 min [standard deviation 7.8] [p = 0.38]). Controlling for measures of activity, such as MVPA, or time spent in long versus short bouts of sedentary time did not modify our results. Differences in sedentary time by self-report between those with and without asthma were not born out by examining sedentary time using objective measures. Further work is necessary to examine the complex interaction among inactivity, obesity, and asthma over time, specifically focusing on whether the type of sedentary activity (e.g., computer vs. television time) is important.

Physical Activity and Sedentary Behavior in the Portuguese Population: What Has Changed from 2008 to 2018?

Assessment of trends in physical activity (PA) and sedentary time (ST) is important for evaluating the effectiveness of national policies and setting goals to improve population PA. This study describes changes in measured PA and ST through motion sensors of the Portuguese population from 2008 to 2018. PA and ST were measured with accelerometry from individuals (≥10 yr) participating in the 2008 ( n = 4 532) and 2018 ( n = 6 369) Portuguese PA Surveillance Systems. Changes were analyzed using generalized linear and logistic models adjusted for accelerometer wear time. A weight factor was applied to all analyses in order to achieve national representativeness of the present results. In 2018, 15.4%, 71.2%, and 30.6% of Portuguese youth, adults, and older adults met the PA recommendations. Compared with 2008, the percentage meeting the PA guidelines increased in youth females (4.7% vs 7.7%, P < 0.05) and adult males (72.2% vs 79.4%, P < 0.05). A decrease in ST was observed for adult males, whereas ST increased in all youth. Male youth decreased the number of breaks in ST (BST per hour), whereas a favorable increase was found for both adult and older adult males and females. PA has remained fairly stable between 2008 and 2018 for all groups, except for youth females and adult males. For ST, a favorable decrease was observed for adult males; however, an inverse trend was found in youth. These results are relevant for policy makers to develop health care policies aimed at promoting PA and reducing ST across all age-groups.

Abstract 34: A Quarter of a Mile More Steps Are Incrementally Associated With Lower Risk of Proximal CVD Events Among Older Adults: Atherosclerosis Risk in Communities (ARIC) Study

Introduction: Steps are an easily interpretable metric that could be used in patient-clinician communication regarding the health benefits of physical activity for cardiovascular disease (CVD). However, most studies are conducted in younger populations with daily steps goals (e.g., 10,000 steps) that may be unsuitable for older adults. Hypothesis: We tested the hypothesis that more daily steps are associated with lower risk of proximal CVD events (within 3.5 years) among older adults (≥70 years). Methods: We analyzed a subsample of participants from the ARIC study visit 6 (2016-17) who wore an accelerometer (ActiGraph GT3X) on the waist ≥3 days for ≥10 hr/day. Daily steps were analyzed continuously and by quartiles. Adjudicated outcomes, through December 2019, included fatal and non-fatal CVD events (coronary heart disease, stroke, and heart failure). Multivariable adjusted Cox proportional hazard models were used to estimate the hazard ratio of CVD events across step measures, adjusted for age, sex, race, education, body mass index (BMI), and accelerometer wear time. Results: Among the 452 adults with step data (mean age = 78.4; 59% women; 20% Black), 7.5% (34/452) had a CVD event over 1,269 person-years of follow-up. Mean (SD) step count was 3447 (1796) steps/day. CVD cumulative incidence was highest among those in the least active step quartile (Q1: &lt;2077 steps/day) (11.5%) compared to the most active quartile (Q4: ≥4453 steps/day) (3.5%). Every 500 steps/day (about 1/4 mile) was associated with a 14% reduced risk of a CVD event (HR = 0.86, 95% CI: 0.76, 0.98). Further, compared to participants in Q1, participants in Q4 had a 77% reduced risk of a proximal CVD event (HR = 0.23, 95% CI: 0.07, 0.83). Cubic spline HR are presented (figure). Conclusions: In this community-based cohort of older adults, every 500 steps (~1/4 of a mile) was associated with a 14% lower risk of a CVD event over 3.5 years of follow-up. Additional follow-up is needed to determine if higher steps prevent or delay CVD or if low steps serve as a biomarker of underlying disease.

Abstract P228: Accelerometer-Derived Daily Steps, Cognition, and Cognitive Impairment in U.S. Community-Dwelling Older Adults: The Atherosclerosis Risk in Communities Study

Introduction: Higher physical activity levels have been shown to preserve cognitive function and prevent cognitive impairment (CI). Whether daily steps, an easily interpretable physical activity metric, is associated with measures of brain health has not been widely studied. Hypothesis: Higher daily step count is associated with better cognitive function and lower odds of CI. Methods: Cross-sectional analysis of ARIC participants (mean age: 78 years, 41% male, 19% Black) who wore an accelerometer (ActiGraph GT3X) on the waist for ≥10 hours on ≥3 days between 2016-17. Daily steps were derived and examined continuously and by quartiles. Global and domain-specific (memory, language, executive function) factor scores were estimated from a battery of cognitive tests. Participants were classified as having CI if they had an adjudicated diagnosis of mild CI or dementia. Hypotheses were tested using linear and logistic regression models, adjusted for age, sex, race, education, and accelerometer wear time. Results: Among 454 participants, 88 (19.4%) had CI. The mean number of daily steps was 3,501 (SD=1,974). In adjusted models, a higher daily step count was associated with better global cognition and executive function factor scores (e.g., those in the 4 th daily-step quartile [≥4,499 steps] vs. 1 st [&lt;2074 steps] had a 0.43 [95% confidence interval: 0.24 to 0.61] higher executive function score). Associations of step count with memory or language scores were not supported. The odds of CI were lower for participants who had a higher daily steps count (e.g., those in the 4 th daily-step quartile vs. 1 st had 62% [odds ratio (OR)=0.38, 95% confidence interval: 0.16 to 0.90] lower odds of CI. The OR of CI for continuous daily steps shown in the Figure. Conclusions: Higher daily steps were associated with better cognitive function and may be a helpful marker in identifying participants with CI. Prospective studies of accelerometer-measured physical activity and cognitive outcomes are needed to understand the direction of these associations.

Greater accelerometer-measured physical activity is associated with better cognition and cerebrovascular health in older adults.

Physical activity (PA) may help maintain brain structure and function in aging. Since the intensity of PA needed to effect cognition and cerebrovascular health remains unknown, we examined associations between PA and cognition, regional white matter hyperintensities (WMH), and regional cerebral blood flow (CBF) in older adults. Forty-three older adults without cognitive impairment underwent magnetic resonance imaging (MRI) and comprehensive neuropsychological assessment. Waist-worn accelerometers objectively measured PA for approximately one week. Higher time spent in moderate to vigorous PA (MVPA) was uniquely associated with better memory and executive functioning after adjusting for all light PA. Higher MVPA was also uniquely associated with lower frontal WMH volume although the finding was no longer significant after additionally adjusting for age and accelerometer wear time. MVPA was not associated with CBF. Higher time spent in all light PA was uniquely associated with higher CBF but not with cognitive performance or WMH volume. Engaging in PA may be beneficial for cerebrovascular health, and MVPA in particular may help preserve memory and executive function in otherwise cognitively healthy older adults. There may be differential effects of engaging in lighter PA and MVPA on MRI markers of cerebrovascular health although this needs to be confirmed in future studies with larger samples. Future randomized controlled trials that increase PA are needed to elucidate cause-effect associations between PA and cerebrovascular health.

Accelerometer-Measured Physical Activity and Sedentary Time among Children in Japan before and during COVID-19: A Cross-Sectional and Longitudinal Analysis.

This study examined changes in physical activity (PA), sedentary behavior (SB), screen time, sleep, and executive function among Japanese preschoolers between COVID-19 pre-pandemic and pandemic periods, using cross-sectional and longitudinal data. Accelerometer data from 63 children aged 5-6 years were collected from three kindergartens in Tokyo, Japan, in late 2019 (pre-COVID-19). This was compared to the data of 49 children aged 5-6 years from the same kindergartens, collected in late 2020 (during COVID-19). Sixteen children in the pre-COVID-19 cohort also participated in the 2020 survey and provided data for the longitudinal analysis. The mean minutes of PA, SB, screen time, and sleep duration, as well as executive function, were compared between the pre- and during COVID-19 cohorts. After adjusting for school, sex, and accelerometer wear time, there were no significant differences in any of the measured outcomes between the two cohorts. However, the analysis of longitudinal data revealed significant increases in time spent in SB and on screens, and a decrease in light-intensity PA and sleep duration during the pandemic compared to the pre-pandemic period. Results suggest that, despite the COVID-19 pandemic, young children's activity levels and SB did not significantly differ from pre-pandemic levels. However, school-aged children's SB, light PA, and sleep time were affected, although this cannot be disentangled from the effects of the transition to school.

Associations of sedentary time, physical activity and fitness with muscle glucose uptake in adults with metabolic syndrome.

To investigate the associations of sedentary time, physical activity, and cardiorespiratory fitness with skeletal muscle glucose uptake (GU). Sedentary time and physical activity were measured with accelerometers, and VO2 max with cycle ergometry in 44 sedentary adults with metabolic syndrome. Thigh muscle GU was determined with [18 F]FDG-PET imaging. Sedentary time (β=-0.374), standing (β =0.376), steps (β =0.351), and VO2 max (β =0.598) were associated with muscle GU when adjusted for sex, age and accelerometer wear time. Adjustment for body fat-% turned all associations non-significant. Body composition is a more important determinant of muscle GU in this population than sedentary time, physical activity, or fitness.

Daily step volume and intensity moderate the association of sedentary time and cardiometabolic disease risk in community-dwelling older adults: A cross-sectional study

ObjectiveTo investigate the moderating effect of step count and peak cadence on the relationship of sedentary time and cardiometabolic disease risk in community-dwelling older adults. MethodsThis cross-sectional study included 248 older adults aged 60–80 years without cardiovascular disease (66.0 ± 4.6 years of age; 78 % females). Sedentary time, step count and peak cadence were measured by a hip-worn accelerometer for seven days. Peak cadence was defined as the average of 30 min of the day (but not necessarily consecutive) with the highest cadence (steps per minute) for all valid days. Cardiometabolic disease risk was defined using a sex-specific continuous metabolic syndrome score (cMetS). Sedentary time was used as an explanatory variable for cMetS and step count and peak cadence as moderators. The analyses were adjusted for known cardiometabolic disease risk factors and accelerometer wear time. The Johnson-Neyman technique was used to specify the value of moderator variables at which the significant relationship between sedentary time and cMetS disappears. ResultsBoth step count (β = −0.186, P = 0.032) and peak cadence (β = −0.003, P = 0.007) showed a moderating effect on the relationship of sedentary time and cMetS. The association of sedentary time and cMetS was not statistically significant (p > 0.05) when step count or peak cadence exceed 5715 steps per day and 57 steps per minute, respectively. ConclusionSteps per day and peak cadence moderate the association of sedentary time and cardiometabolic disease risk in older adults. Therefore, steps per day and peak cadence seem to offset the deleterious effects of sedentary time on cardiometabolic health in this population.

Association of Accelerometer-Measured Physical Activity and Sedentary Time with Epigenetic Markers of Aging.

Physical activity may influence chronic disease risk, in part, through epigenetic mechanisms. Previous studies have demonstrated that an acute bout of physical activity can influence DNA methylation status. Few studies have explored the relationship between habitual, accelerometer-measured physical activity or sedentary time with epigenetic markers of aging. We used linear regression to examine cross-sectional associations of accelerometer-measured physical activity and sedentary time with extrinsic and intrinsic epigenetic age acceleration (EEAA and IEAA) models and GrimAge measured from blood samples from Framingham Heart Study participants with accelerometry and DNA methylation data ( n = 2435; mean age, 54.9 ± 14.3; 46.0% men). Residuals of Hannum-, Horvath-, and GrimAge-predicted epigenetic age were calculated by regressing epigenetic age on chronological age. We took into account blood cell composition for EEAA, IEAA, and AdjGrimAge. Moderate to vigorous physical activity was log-transformed to normalize its distribution. Adjustment models accounted for family structure, age, sex, smoking status, cohort-laboratory indicator, and accelerometer wear time. We additionally explored adjustment for body mass index (BMI). Walking 1500 more steps per day or spending 3 fewer hours sedentary was associated with >10 months lower GrimAge biological age (or ~1 month lower AdjGrimAge, after adjusting for blood cells, P < 0.05). Every 5 min·d -1 more moderate to vigorous physical activity was associated with 19-79 d of lower GrimAge (4-23 d lower using EEAA or AdjGrimAge, P < 0.01). Adjusting for BMI attenuated these results, but all statistically significant associations with AdjGrimAge remained. Greater habitual physical activity and lower sedentary time were associated with lower epigenetic age, which was partially explained by BMI. Further research should explore whether changes in physical activity influence methylation status and whether those modifications influence chronic disease risk.

Associations Between Physical Activity, Fundamental Motor Skills, And Physical Fitness In Norwegian Preschooler`s

PURPOSE: The importance of moderate-to-vigorous physical activity (MVPA) for physical fitness (FIT) and motor development is well established in school-aged children and adolescents. As many children have suboptimal motor skills and FIT, early childhood has been highlighted as an important phase for optimizing MVPA levels, and such, possibly improve FIT and motor skills. However, the relationship between MVPA and FIT and motor skills have had limited testing in preschool populations. The aim of this study was to investigate cross-sectional associations between MVPA and a broad set of motor skill and FIT measures in a large sample of preschoolers. METHODS: A sample of 1047 children (mean age 4.3 yr, 52% boys) from the Active Learning Norwegian Preschool(er)s Study participated during 2020-2021. MVPA was measured by accelerometry (Actigraph GT3x+) for 7 days and data were analysed using 1-sec epoch. MVPA was defined as ≥2296 counts. FMS were evaluated by a process-oriented test battery (9 items) across the domains: total score, locomotor, object control, and balance skills. FIT was assessed through three tests including speed-agility, hand grip, and standing long jump. A linear mixed model adjusted for sex, age, BMI (kg/m2), accelerometer wear time, and test person, was applied. RESULTS: There were significant, positive associations between MVPA and total skill score (β (95 % CI): 18 (13.8, 22.2), p < 0.001), locomotor- (14 (10.6, 17.3), p < 0.001), object control- (11.8 (8.5, 15.1), p < 0.001), and balance skills (5.4 (2.5, 8.3), p < 0.001), long jump (0.2 (0.2, 0.3), p < 0.001), and hand grip (1,2 (0.7, 1.7), p < 0.001), and a negative association with speed-agility (-1.6 (-2, -1.2), p < 0.001). CONCLUSIONS: Our findings demonstrate that MVPA is favorably and strongly associated with many dimensions of motor skills and FIT in preschoolers. As physical activity is a modifiable behavior, our findings suggests that promotion of MVPA might improve children’s motor skills and FIT levels during early childhood.

S08-4 In terms of individual fitness, people with low cardiorespiratory fitness are physically the most active

Abstract Background Depending on cardiorespiratory fitness (CRF), people may perceive differently the exertion of incident physical activity (PA). It has been proposed to use thresholds relative to individual fitness in PA monitoring when it is feasible. Methods 1952 adults (803 men, 1149 women), aged 20-69 years participated in the FinFit2017 (EUPASMOS) -study. Their VO2max was predicted with 6 min walking test and they had accelerometer wear time at least four days with minimum of 24 h/day during seven consecutive days of measurement period. The participants were divided into CRF thirds by age groups and sex. Acceleration data was analyzed in 6s epochs and intensity in MET (metabolic equivalent) values was calculated for each epoch. MET values were smoothed with 1min exponential moving average. The epoch activity was classified into moderate-to-vigorous PA (MVPA) using both absolute (3.0MET) and individual (40% of the oxygen uptake reserve) thresholds. The accumulated MVPA time was calculated for bouts at least 0.1, 1.5, 3.0, 5.0, 10.0, 15.0, 20.0, 30.0 and 60.0 minutes. Population-weighted average of accumulated PA times in CRF-thirds and partial Spearman correlations controlled by age and sex between bout lengths and VO2max were calculated for both absolute and relative thresholds. Results Participants in the lowest CRF-third accumulated the most (p &amp;gt; 0.05) MVPA time with relative threshold (22min (low); 15min (middle); 12min (high)) and the highest third (40min (low); 50min (middle); 56min (high)) with absolute threshold. The correlations were negative with individual thresholds, if short bouts were counted into accumulated time, and significant positive correlation (r = 0.048) was achieved only with at least 60.0min bouts. The correlations were significantly positive for all bout lengths with absolute thresholds and the highest correlation was achieved with at least 0.1min bouts (r = 0.295). Conclusions The lowest fitness third was the most active when the PA intensity was analyzed using relative thresholds. Their PA was mostly accumulated from short, few minute bouts. Thus, they had to utilize more of their aerobic capacity on daily basis just to keep up with their daily routines and the peers.

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).

IMPACT: A Randomized Controlled Trial of an mHealth Physical Activity Intervention for Young Adult Cancer Survivors

Purpose: The IMPACT trial evaluated a theory-based mobile physical activity (PA) intervention on total PA (primary) and moderate-to-vigorous (MVPA) at 6 months in a nationwide sample of young adult cancer survivors (YACS). Methods: YACS (N=280) were randomized to either an intervention group or a self-help (control) group. All participants received digital tools (activity tracker, smart scale, Facebook group) and an individual videochat session. Intervention participants also received a 6-month mHealth program with components to promote increased PA (behavioral lessons, adaptive goal-setting, tailored feedback, tailored text messages, Facebook group prompts). PA was assessed via accelerometry and online questionnaire (Godin Leisure Time Exercise Questionnaire) at baseline and 6 months. Using linear mixed models and an intention-to-treat approach, we tested for group differences in changes from baseline to 6 months, adjusting for education, time since diagnosis, age, and accelerometer wear time. Results: Of 280 YACS (M=33.4 (SD 4.8) yrs, 81.8% women, 23.2% racial/ethnic minority individuals), 92.9% completed 6-month measures. Device-measured total PA min/wk (i.e., sum of light, moderate, and vigorous PA) increased from a mean of 1974.3 (SD=673.9) to 2024.3 (686.7) at 6 months in the intervention group (p=.26) and from 1814.9 (704.5) to 1877.7 (758.2) in the control group (p=.43), with no difference between groups (p=.84). Both groups increased MVPA min/wk over 6 months; increases were 24.7 min/wk (95% CI: 14.8, 34.6; p&amp;lt;.0001) in the intervention versus 11.4 min/wk (95% CI: 1.4, 21.4; p=.02) in the control (p=.07 between groups). Increases in MVPA were 99.7% and 41.6% over baseline in the intervention and control groups, respectively. Increases in self-reported total PA were significant; 123.3 min/wk (95 CI%: 94.5, 152.1; p&amp;lt;.0001) in the intervention versus 83.40 (95% CI: 49.30, 117.50; p&amp;lt;.0001) in the control (p=.08 between groups). Conclusions: While both groups increased total PA over 6 months, the intervention doubled the increase in MVPA min/wk relative to the control group, which is associated with important health benefits. Future research should examine moderators of effects to identify for whom, and under what conditions, the effectiveness varied.

Workers' Activity Profiles Associated With Predicted 10-Year Cardiovascular Disease Risk.

Background There is a need to explore common activity patterns undertaken by workers and the association between these activity profiles and cardiovascular disease (CVD). This study explored the number and type of distinct profiles of activity patterns among workers and the association between these profiles and predicted 10-year risk for a first atherosclerotic CVD event. Methods and Results Distinct activity patterns from a cross-section of workers' accelerometer data were sampled from Canadian Health Measures Survey participants (5 cycles, 2007-2017) and identified using hierarchical cluster analysis techniques. Covariates included accelerometer wear time, work factors, sociodemographic factors, clinical markers, and lifestyle variables. Associations between activity profiles and high atherosclerotic CVD risk >10% were estimated using robust Poisson regression models. Six distinct activity profiles were identified from 8909 workers. Compared with the "lowest activity" profile, individuals in the "highest activity" and "moderate evening activity" profiles were at 42% lower risk (relative risk [RR], 0.58; 95% CI, 0.47, 0.70) and 33% lower risk (RR, 0.67; 95% CI, 0.44, 0.87) of predicted 10-year atherosclerotic CVD risk of >10%, respectively. "Moderate activity" and "fluctuations of moderate activity" profiles were also associated with lower risk estimates, whereas the "high daytime activity" profile was not statistically different to the reference profile. Conclusions Workers accumulating physical activity throughout the day and during recreational hours were found to have optimal CVD risk profiles. Workers accumulating physical activity only during daytime work hours were not associated with reduced CVD risk. Findings can inform alternative strategies to conferring the cardiovascular benefits of physical activity among workers. Large prospective studies are needed to confirm these findings.

Use of the ORBIT model to refine and test a novel approach to exercise promotion for breast cancer survivors based on affect regulation.

TPS12153 Background: Physical inactivity is a modifiable risk factor for breast cancer recurrence, but estimates suggest at least 50% of breast cancer survivors are insufficiently active. Guidelines specify all cancer survivors should avoid inactivity, and 90-minutes of moderate-vigorous physical activity (MVPA) per week is associated with clinically meaningful benefits (e.g., reduced cancer-related fatigue). Among the general population, how people feel during exercise (i.e., “affective response to exercise”) predicts future exercise engagement. Past work shows prescribing affect-regulated exercise can increase MVPA among inactive adults; however, this strategy has yet to be tested with cancer survivors. The overarching goal of this trial-in-progress is to test the hypothesis that an affect-regulated exercise prescription (Affect-Rx) can promote clinically meaningful increases in MVPA among inactive breast cancer survivors. Methods: Design: The Obesity-Related Behavioral Intervention Trials (ORBIT) model was used to inform all choices about design and key research milestones for two sequential studies. Study 1 (Phase Ib) is a stakeholder-centered, single-arm pilot trial (NCT04903249). Study 2 (Phase IIa) is a randomized (2:1) proof-of-concept trial. In both studies, MVPA will be measured using waist-worn ActiGraph wGT3X-BT accelerometers for 10 days at baseline, 2-, 6- and 12-weeks follow-up. Participants also complete brief ecological momentary assessments (EMAs) of their feeling states (e.g., pain, fatigue) three times per day for the same 10-day data collection periods. Participants: &gt;18 years or older, physically inactive, stage 0-III breast cancer survivors, with primary cancer-treatment completed within the last 5-years. Intervention: Both studies deliver the Affect-Rx prescription: Exercise at the highest pace that still feels good. The Control condition in Study 2 is a heart-rate regulated exercise prescription. Endpoints and Planned Analyses: The goal of Study 1 is to refine the study protocol for acceptability via participant interviews and objective indicators of acceptability (e.g., accelerometer wear-time). The primary milestone for Study 1 is a fixed protocol ready for testing in Study 2. The goal of Study 2 is to quantify the effect of Affect-Rx on MVPA at 12-weeks relative to Control. The primary milestone for Study 2 is clinically meaningful impact on MVPA operationalized as &gt;50% participants completing 90-minutes of MVPA at the end of 12 weeks. The associations between daily variability in feeling states and MVPA will be analyzed using a mixed-effects, hierarchical regression modeling approach. Current Enrollment: Data collection for Study 1 are ongoing. To date, N = 37 women have enrolled in Study 1 and data collection is complete for N = 13 at week-12. We aim to collect complete data from at least N = 20 women in Study 1 and N = 60 women in Study 2. Clinical trial information: NCT04903249.