Minutes Of Moderate-to-vigorous Physical Activity Research Articles

A Pedometer-Based Physically Active Learning Intervention: The Importance of Using Preintervention Physical Activity Categories to Assess Effectiveness.

To assess physical activity outcomes of a pedometer-based physically active learning (PAL) intervention in primary school children. Six paired schools were randomly allocated to either a 6-week teacher-led pedometer-based physically active learning intervention or a control (n = 154, female = 60%, age = 9.9 [0.3]y). Accelerometers assessed total daily sedentary time, light physical activity (LPA), and moderate-to-vigorous physical activity (MVPA). Preintervention mean daily MVPA minutes grouped participants as Low Active (<45min/d) and High Active (≥45min/d). From the final sample size, the intervention (n = 52) significantly improved LPA versus control (n = 31, P = .04), by reducing sedentary time. More intervention (+10%) than control (+3%) pupils met the 60 minutes per day guidelines. In both intervention subgroups, pupils spent less time in LPA (P < .05) versus control. The greatest nonsignificant increase was found in the Low Active pupils MVPA levels. Improvements in LPA were statistically significant in the intervention versus control group. In subgroup analysis, Low Active pupils in the intervention showed the greatest beneficial effects and the Most Active pupils may have replaced MVPA and sedentary time with LPA. The intervention group housed clusters of pupils showing variable responsiveness, justifying routine examination of subgroup variability in future studies.

Are school-based physical activity interventions effective and equitable? A meta-analysis of cluster randomized controlled trials with accelerometer-assessed activity.

SummaryThe prevalence of childhood obesity is increasing at epidemic rates globally, with widening inequalities between advantaged and disadvantaged groups. Despite the promise of schools as a universal context to access and influence all children, the potential of school‐based interventions to positively impact children's physical activity behaviour, and obesity risk, remains uncertain. We searched six electronic databases to February 2017 for cluster randomized trials of school‐based physical activity interventions. Following data extraction, authors were sent re‐analysis requests. For each trial, a mean change score from baseline to follow‐up was calculated for daily minutes of accelerometer‐assessed moderate‐to‐vigorous physical activity (MVPA), for the main effect, by gender, and by socio‐economic position (SEP). Twenty‐five trials met the inclusion criteria; 17 trials provided relevant data for inclusion in the meta‐analyses. The pooled main effect for daily minutes of MVPA was nonexistent and nonsignificant. There was no evidence of differential effectiveness by gender or SEP. This review provides the strongest evidence to date that current school‐based efforts do not positively impact young people's physical activity across the full day, with no difference in effect across gender and SEP. Further assessment and maximization of implementation fidelity is required before it can be concluded that these interventions have no contribution to make.

Predicting accelerometer-based physical activity in physical education and total physical activity: The Self-determination Theory approach

The present study tested the motivational model of physical education (PE) including needs for competence, autonomy, social relatedness, intrinsic and extrinsic motivation, in-class moderate to vigorous physical activity (MVPA), and total MVPA. Participants were 490 (264 girls, 226 boys) Finnish elementary school students. The data were collected using accelerometers and questionnaires for a seven-day period during the fall semester 2017. The key findings were that 1) social relatedness associated with total MVPA via in-class MVPA in girls, whereas competence was linked to in-class MVPA through extrinsic motivation in boys, 2) competence was positively linked to extrinsic motivation in a similar way in both girls and boys, 3) social relatedness and in-class MVPA were positively associated with total MVPA in both girls and boys, 4) competence, autonomy, and relatedness were positively linked to intrinsic motivation in girls when only competence and autonomy were related to intrinsic motivation in boys, and 5) in-class MVPA contributed 36% of total weekly MVPA minutes in the present sample. Although the indirect relationships between study variables did not fully support the existing PE motivational model, the direct associations showed that needs of competence, autonomy, relatedness could be promoted in PE classes to support intrinsic motivation, and total MVPA.

Minimal Important Difference for Physical Activity and Validity of the International Physical Activity Questionnaire in Interstitial Lung Disease.

The optimal method of physical activity measurement has not been determined in patients with fibrotic interstitial lung disease (ILD). To assess the validity, internal consistency, and responsiveness of the International Physical Activity Questionnaire long form (IPAQ-LF) and to estimate the minimal important difference (MID) for moderate to vigorous physical activity (MVPA) in patients with fibrotic ILD. This two-center prospective cohort study included a convenience sample of 111 outpatients with fibrotic ILD who wore waist and wrist ActiGraph accelerometers for 7 consecutive days, followed by self-administration of the IPAQ-LF. Both measurements were performed at baseline and 6-month follow-up. Spearman rank correlations were used to evaluate the IPAQ-LF validity in comparison to activity monitor data, lung function, step count, and quality of life. The internal consistency of the IPAQ-LF was determined using Cronbach's α. Self-reported changes in IPAQ-LF parameters were compared among tertiles of change measured by the waist activity monitor to assess the responsiveness of the IPAQ-LF after 6 months. Anchor- and distribution-based methods were used to estimate the MID for MVPA. Self-reported MVPA minutes, activity-related energy expenditure, sedentary time, and inactive time of the IPAQ-LF generally showed moderate to strong correlations with corresponding waist activity monitor data, step count, lung function, and quality of life. The Cronbach's α of the IPAQ-LF was 0.78. The IPAQ-LF was responsive at detecting increases in weekly MVPA and energy expenditure. The MIDs for MVPA were 8 to 26 and 13 to 58 min/wk using the anchor-based method for waist activity monitor and IPAQ-LF data, respectively. The distribution-based MID estimate for MVPA was 104 to 242 min/wk. The IPAQ-LF has acceptable validity and internal consistency for measuring daily physical activity in patients with fibrotic ILD. The IPAQ-LF was responsive at detecting increases in physical activity but limited in its ability to detect declines or changes in inactivity. Using an anchor-based approach, the MID for MVPA measured by a waist activity monitor is approximately 26 min/wk.

Fourth Graders’ Objectively Measured Week Long Physical Activity

We explored 10–11 year-old children’s moderate to vigorous physical activity (MVPA) to describe how it is distributed within weekdays, weekend days, the segments of a schoolday and how it meets the global recommendation of ≥ 60 min daily MVPA. Participants were from two fourth classes (N = 33; 20 boys, 13 girls) in the city of Vantaa, capitol area of Finland. PA was measured using a Polar Active® (PAC) wrist-worn accelerometer. A diary supported the accelerometer data. Raw metabolic equivalent (MET) data from accelerometers were transmitted to computer, organized and uploaded to SPSS. We used MET-thresholds moderate PA (MPA) ≥ 3 6, vigorous (VPA) ≥ 6 and consequently moderate to vigorous PA (MVPA) ≥ 3. Average daily MVPA was 92 minutes. Differences between weekdays and weekend days existed, but they were at least partly caused by the weather. Global recommendation was met by 21%, more often by girls than boys. However, almost everyone met the recommendation ≥ 4 a week. In segments of the schoolday (lessons, long recesses, short recesses and lunch breaks) the children were physically quite active at 5, 12, 4 and 8 minutes, respectively. Hypothetically summed up, a schoolday accumulated 50 minutes MVPA. Boys accumulated quite systematically slightly more MVPA during schooldays and leisure time. Schooldays play an important role in children’s total MVPA and the current situation is decent. However, teacher educators, decision makers, school administration, principals, teachers and school staff should still aim at finding new ways of making schooldays even more physically active.

Within and between-day differences in adolescents’ objectively-measured physical activity and sedentary behavior

A decline in adolescents’ moderate-to-vigorous physical activity (MVPA) and the increase in their sedentary behavior (SB) have been registered all over the world. In order to increase the MVPA and reduce the SB of adolescents, their day has been analyzed by segments of time, verifying the contribution of each to the daily recommendation of 60 minutes/day. Previous studies have been centered only in physical activity markers, but the SB variables were not compared nor the segments of the school-recess with the out-of-school period or with the weekend. This study aimed to examine the intra- and inter-days differences in the objectively measured levels of PA and SB in adolescents. A sample of 156 Chilean school students (87 boys and 69 girls; M age=13.41; SD=.67 years) participated in the present study. Participants’ PA and SB were objectively measured by a GT3X accelerometer. Overall results showed that only 14% and 9% of Chilean adolescents achieved the daily recommendation of 60 minutes of MVPA on weekdays and the weekend, respectively. School recess was found the best moment for developing MVPA, followed by out-of-school time, and ending with weekend days presenting the worst scenario. Regarding the SB, Chilean adolescents were involved in SB 69.39% of the time on weekdays, and over 70% during the weekend. Different strategies are discussed in order to increase the MVPA and to decrease SB in each segment of a day.

Are school-based physical activity interventions effective and equitable? A systematic review and meta-analysis of cluster randomised controlled trials

BackgroundChildhood obesity is increasing globally, with widening inequalities by socioeconomic status and sex. The aim of this study was to assess the efficacy of school-based physical activity interventions on children's daily moderate-to-vigorous physical activity (MVPA), and variations in efficacy by sex and socioeconomic status. MethodsWe systematically searched six electronic databases (ERIC, EMBASE, OVID Medline, PsycINFO, Scopus, SPORTDiscus) from inception to Feb 24, 2017. Search terms included “children”, “physical activity”, “cluster-randomized controlled trial”, and “accelerometer”. Inclusion was restricted to trials published in English of school-based physical activity interventions with accelerometer-assessed MVPA across the full day. After duplicate data extraction and quality assessment, lead authors were sent re-analysis requests. For each trial a mean change score from baseline to follow-up was calculated for daily minutes of accelerometer-assessed MVPA, for the main effect, by sex, and by socioeconomic status. Effects were pooled in random effects meta-analyses. Heterogeneity was explored with meta-regressions and subgroup meta-analyses. This study is registered with PROSPERO, CRD42017062565. Findings25 trials met the inclusion criteria; 17 trials (9044 participants) of predominantly multicomponent (88%), multisetting interventions (77%) provided relevant data and were included in meta-analyses. There was no effect of activity interventions on MVPA (standardised mean difference [SMD] 0·02, 95% CI −0·07 to 0·11). There was no evidence of differential efficacy by sex (SMD girls 0·07, 95% CI −0·07 to 0·21; boys 0·05, −0·09 to 0·19) or socioeconomic status (low −0·01, −0·12 to 0·11; middle −0·06, −0·17 to 0·05; high −0·01, −0·13 to 0·11). InterpretationThis review provides strong evidence that current school-based efforts do not increase young people's daily physical activity, with no difference in effect across sex and socioeconomic status. This is the first meta-analysis, to our knowledge, of children's physical activity interventions to pool accelerometer data with comparable outcome metrics. Our findings conflict with most previous syntheses, which have included substantial self-report data and reported positive effects. Further assessment, maximisation of implementation fidelity, and consideration of wider (including health) benefits is needed before these interventions can be concluded to have no contribution to make to children's health promotion. Until then we recommend that interventions are limited to research contexts. FundingMedical Research Council, British Heart Foundation, Cancer Research UK, Economic and Research Council, National Institute for Health Research, Wellcome Trust, Gates Cambridge.

Self-Reported Physical Activity Level in Student Athletes at Preparticipation Physical Evaluations.

Quantify physical activity in healthy student athletes. Cross-sectional survey. Five Central Ohio schools during mass preparticipation physicals. Three hundred sixty-five children between the ages 10 and 18 years. Days per week of moderate to vigorous physical activity (MVPA), minutes per day of MVPA, and number of activities. Minutes per week of MVPA. One hundred eighty high school and 177 middle school subjects responded to the survey. There were 198 male and 162 female respondents. Mean age recorded 14.2 ± 1.7 years. There were no differences in activity volume based on sex. Mean minutes per week of MVPA reported 316.0 ± 231.0. High school subjects reported fewer activities than middle school cohort 2.7 ± 1.2 versus 3.2 ± 1.5 (P < 0.05). Only 7% of respondents reported exercising 60 minutes daily. Twenty-seven percent of respondents met minutes per week (420 minutes of MVPA) by training in large volumes on fewer days. Surprisingly, this physically active population did not meet the national standards of daily MVPA. In addition, middle school athletes reported more variety of activities compared with high school athletes surveyed which reached statistical significance. Screening for daily physical activity is important in the athletic population because young athletes may not meet daily MVPA recommendations.

Descriptive epidemiology of accelerometer-measured moderate to vigorous physical activity in Japanese older adults

Most physical activity (PA) guidelines for health promotion recommend moderate to vigorous PA (MVPA) lasting at least 10 minutes (long-bout MVPA). However, recent studies have shown the beneficial effects of short-bout MVPA (intermittent and lasting <10 minutes). Therefore, we aimed to clarify the detailed patterns of MVPA of community-dwelling older adults using accelerometers. This is a cross-sectional descriptive study. Community-dwelling older Japanese adults (total: 1,210; 70-80 years of age) randomly selected from residential registries of 3 municipalities (Bunkyo, Fuchu, and Oyama) were asked to wear an accelerometer (HJA-350 IT; Omron Healthcare, Japan). MVPA was classified by bout length (1-4, 5-9, 10-19, 20-29, and > 30 minutes). The mean frequency and duration of MVPA by each bout length and the proportion of long-bout MVPA were described. Valid data were obtained from 450 participants (men: 56.7%; mean age: 74 years). The mean±standard deviation of the frequency and duration of MVPA bouts were 21.8±14.6 times/day and 2.1±0.9 min, respectively. The total duration of MVPA was 46.5±33.0 min/day. Long-bout MVPA accounted for 26.9%±23.5% of daily MVPA, whereas MVPA of 1-4 minutes accounted for 43.4%. Older adults performed about 45 minutes of MVPA a day, but most of this was short-bout MVPA, which is overlooked by current WHO PA guidelines. In particular, short-bout MVPA was frequent among older women and those living in rural areas.

Are We Overestimating Physical Activity Prevalence in Children?

Physical activity guidelines state that children should achieve at least 60 minutes of moderate to vigorous physical activity (MVPA) on each day of the week. Accurate assessment of adherence to these guidelines should, ideally, include measurement over 7 days. When less than 7 days of data are available, researchers often report the average minutes of MVPA per day as a proxy for 7-day measurement. The aim of this study was to compare prevalence estimates generated by average MVPA per day versus MVPA assessed over 7 days. Data were collected as part of the Healthy Lifestyles Programme. One class from each school was randomized to wear a GENEActiv accelerometer for 8 days. The percentages of children achieving an average of ≥60 minutes of MVPA per day and those achieving ≥60 minutes of MVPA on each of 7 days were calculated. A total of 807 children provided 7 days of data. When the average MVPA per day was calculated, 30.6% (n = 247) of children accumulated ≥60 minutes of MVPA per day. Only 3.2% (n = 26) accumulated ≥60 minutes of MVPA on every day of the week. Previous studies utilizing average MVPA per day are likely to have overestimated the percentage of children meeting recommendations.

Moderate to vigorous physical activity and impact loading independently predict variance in bone strength at the tibia but not at the radius in children.

The objectives of this study were (i) to assess whether daily minutes of moderate to vigorous physical activity (MVPA) or vigorous physical activity (VPA) and impact counts (acceleration peaks ≥3.9g) independently predict variance in bone strength in children and youth and (ii) to estimate bone strength gain associated with increases in daily MVPA, VPA, or impact counts. We recorded 7-day activity of 49 participants (mean age 11.0 years, SD 1.7) using accelerometers and estimated radius and tibia bone strength using peripheral quantitative computed tomography. We used linear regression models adjusted for sex, body mass, and muscle area to address our objectives. Daily MVPA (mean 50 min, SD 23) and VPA (mean 17 min, SD 11) or impacts (mean 71 counts, SD 59) did not predict variance in radius strength. Daily VPA (β = 0.24) predicted variance in tibia strength at the distal and shaft sites, and shaft strength was also predicted by MVPA (β = 0.20) and impact counts (β = 0.21). Our models estimated a 3%-6%, 4%, or 4%-11% gain in tibia strength after increasing daily MVPA by 10-20 min, VPA by 5 min, or impacts by 30-100 counts, respectively. In conclusion, daily minutes of MVPA or VPA and impact counts are independent predictors of tibia but not radius strength. Objective recording of activities associated with forearm bone strength and trials testing the efficacy of increasing daily MVPA, VPA, and related impacts on bone strength development in children and youth are warranted.

Physical activity and dentate gyrus volume in pediatric acquired demyelinating syndromes.

ObjectiveTo assess the association between daily moderate-to-vigorous physical activity (MVPA) and dentate gyrus volume (DGv) in pediatric patients with acquired demyelinating syndromes (ADSs) of the CNS.MethodsCross-sectional analysis of accelerometry (7 days) and research protocol MRI data from 12 pediatric MS and 18 children with monophasic ADS (monoADS). Total brain and DGv were quantified using standardized methods. The association of daily minutes of MVPA with normalized DGv (nDGv) was assessed using multivariable generalized linear models.ResultsMedian (interquartile range) MVPA was lower in MS patients [9.5 (14)] and exhibited less variation than in monoADS patients [24.5 (47)]. nDGv did not differ significantly between groups [mean nDGv (SD) [cm3]: MS 0.34 (0.1); monoADS 0.4 (0.1); p = 0.100]. In the monoADS group, every 1-minute increase in MVPA was associated with a 2.4-mm3 increase in nDGv (p = 0.0017), an association that was independent of age at incident demyelination, time from incident demyelination, sex, and brain white matter T2 lesion volume. No significant association was found between MVPA and nDGv (−2.6 mm3/min, p = 0.16) in the MS group.ConclusionsHigher MVPA associates with greater nDGv in children who have recovered from monophasic demyelination. Larger studies are required to determine whether MVPA can promote regional brain development, or limit tissue damage, in youth with MS.

Methods for Activity Monitor Validation Studies: An Example With the Fitbit Charge

Purpose: To advance research practices with consumer monitors, standard validation methods are needed. This study provides an example of best practices through systematically evaluating the validity of the Fitbit Charge (FBC) under free-living conditions using a strong reference measure and robust measurement agreement methods. Methods: 94 healthy participants (Mage 41.8 ±9.3 yrs) wore a FBC and two research grade accelerometers (Actigraph GT3X and activPAL) as they went about normal activities for a week. Estimated daily minutes of moderate to vigorous physical activity (MVPA) from the FBC were compared against reference estimates obtained from the Sojourns Including Posture (SIP) methodology, while daily step counts were compared against the activPAL. Results: Correlations with reference indicators were high for average daily MVPA (r = 0.8; p &lt; .0001) and steps (r = 0.76; p &lt; .0001), but the FBC overestimated time spent in MVPA by 56% and steps by 15%. The mean absolute percent errors of MVPA and steps estimated by FBC were 71.5% and 30.0%, respectively. Neither of the MVPA and step estimates from the FBC fell into the ±10% equivalence zone set by the criterion. The Kappa statistics of the classification agreement between the two MVPA assessment methods was 0.32 with a low sensitivity of 30.1% but a high specificity of 96.7%. Conclusion: The FBC overestimated minutes of MVPA and steps when compared to both reference assessments in free-living conditions. Standardized reporting in future studies will facilitate comparisons with other monitors and with future versions of the FBC.

Web-Based Intervention Using Behavioral Activation and Physical Activity for Adults With Depression (The eMotion Study): Pilot Randomized Controlled Trial.

BackgroundPhysical activity is a potentially effective treatment for depression and depressive relapse. However, promoting physical activity in people with depression is challenging. Interventions informed by theory and evidence are therefore needed to support people with depression to become more physically active. eMotion is a Web-based intervention combining behavioral activation and physical activity promotion for people in the community with symptoms of depression.ObjectiveThe objectives were to assess the feasibility and acceptability of delivering eMotion to people in the community with symptoms of depression and to explore outcomes.MethodsParticipants with elevated depressive symptoms were recruited from the community through various methods (eg, social media) and randomized to eMotion or a waiting list control group for 8 weeks. eMotion is an administratively supported weekly modular program that helps people use key behavior change techniques (eg, graded tasks, action planning, and self-monitoring) to re-engage in routine, pleasurable, and necessary activities, with a focus on physical activities. Feasibility data were collected that included the following: recruitment and trial retention rates; fidelity of intervention delivery, receipt, and enactment; and acceptability of the intervention and data collection procedures. Data were collected for the primary (depression) and secondary outcomes (eg, anxiety, physical activity, fidelity, and client satisfaction) at baseline and 2 months postrandomization using self-reported Web-based questionnaires and accelerometers. Delivery fidelity (logins, modules accessed, time spent) was tracked using Web usage statistics. Exploratory analyses were conducted on the primary and secondary outcomes.ResultsOf the 183 people who contacted the research team, 62 were recruited and randomized. The mean baseline score was 14.6 (SD 3.2) on the 8-item Patient Health Questionnaire depression scale (PHQ-8). Of those randomized, 52 participants provided accelerometer-recorded physical activity data at baseline that showed a median of 35.8 (interquartile range [IQR] 0.0-98.6) minutes of moderate-to-vigorous physical activity (MVPA) recorded in at least 10-minute bouts per week, with only 13% (7/52) people achieving guideline levels (150 minutes of MVPA per week). In total, 81% (50/62) of participants provided follow-up data for the primary outcome (PHQ-8), but only 39% (24/62) provided follow-up accelerometer data. Within the intervention group, the median number of logins, modules accessed, and total minutes spent on eMotion was 3 (IQR 2.0-8.0), 3 (IQR 2.0-5.0), and 41.3 (IQR 18.9-90.4), respectively. Acceptability was mixed. Exploratory data analysis showed that PHQ-8 levels were lower for the intervention group than for the control group at 2 months postrandomization (adjusted mean difference −3.6, 95% CI −6.1 to −1.1).ConclusionsIt was feasible to deliver eMotion in UK communities to inactive populations. eMotion has the potential to be effective and is ready for testing in a full-scale trial. Further work is needed to improve engagement with both the intervention and data collection procedures.Trial RegistrationClinicalTrials.gov NCT03084055; https://clinicaltrials.gov/ct2/show/NCT03084055 (Archived by WebCite at http://www.webcitation.org/6zoyM8UXa)

Physical Activity and Health-Related Fitness of Adolescents within the Juvenile Justice System.

Background The purpose of this study was to examine the physical activity patterns and health-related fitness levels of adolescents within the Juvenile Justice System. Methods Participants included 68 adolescents (Mean age = 17.1 ± 1.0 years) in two secure Juvenile Justice correctional facilities in the Western USA. Moderate-to-vigorous physical activity (MVPA) was monitored for one week using the ActiGraph GT9X accelerometer. Health-related fitness was measured using the FITNESSGRAM test battery. Results Adolescents averaged 43.3±21.6 minutes of MVPA per weekday compared to 42.7±27.5 per weekend day. During school hours, adolescents accumulated 17.1±9.0 minutes of MVPA compared to 5.9±3.4 minutes before school and 21.0±13.6 minutes after school. Adolescents averaged 18.9±11.0 push-ups, 44.5±26.4 curl-ups, 34.7±24.8 PACER laps, and 22.1%±10.0% body fat. Conclusions Adolescents within the Juvenile Justice System are falling short of the recommended 60 minutes of MVPA per day and 30 minutes of MVPA during school and also need to improve their health-related fitness, especially cardiorespiratory endurance.

Validating Fitbit Zip for monitoring physical activity of children in school: a cross-sectional study

BackgroundModern activity trackers, including the Fitbit Zip, enable the measurement of both the step count as well as physical activity (PA) intensities. However, there is a need for field-based validation studies in a variety of populations before using trackers for research. Therefore, the purpose of the current study was to investigate the validity of Fitbit Zip step count, moderate to vigorous physical activity (MVPA) and sedentary minutes, in different school segments in 3rd grade students.MethodsThird grade students (N = 147, aged 9–10 years) wore a Fitbit Zip and an ActiGraph GT3x-BT accelerometer simultaneously on a belt for five days during school hours. The number of steps, minutes of MVPA and sedentary time during class time, physical education lessons and recess were extracted from both devices using time filters, based on the information from school time tables obtained from class teachers. The validity of the Fitbit Zip in different school segments was assessed using Bland-Altman analysis and Spearman’s correlation.ResultsThere was a strong correlation in the number of steps in all in-school segments between the two devices (r = 0.85–0.96, P < 0.001). The Fitbit Zip overestimated the number of steps in all segments, with the greatest overestimation being present in physical education lessons (345 steps). As for PA intensities, the agreement between the two devices in physical education and recess was moderate for MVPA minutes (r = 0.56 and r = 0.72, P < 0.001, respectively) and strong for sedentary time (r = 0.85 and r = 0.87, P < 0.001, respectively). During class time, the correlation was weak for MVPA minutes (r = 0.24, P < 0.001) and moderate for sedentary time (r = 0.57, P < 0.001). For total in-school time, the correlation between the two devices was strong for steps (r = 0.98, P < 0.001), MVPA (r = 0.80, P < 0.001) and sedentary time (r = 0.94, P < 0.001).ConclusionIn general, the Fitbit Zip can be considered a relatively accurate device for measuring the number of steps, MVPA and sedentary time in students in a school-setting. However, in segments where sedentary time dominates (e.g. academic classes), a research-grade accelerometer should be preferred.

Intervention Effects of "Girls on the Move" on Increasing Physical Activity: A Group Randomized Trial.

Limited intervention success in increasing and sustaining girls' moderate-to-vigorous physical activity (MVPA) underscores a need for continued research. The aim of this study was to evaluate the effect of a 17-week Girls on the Move (GOTM) intervention on increasing MVPA among fifth- to eighth-grade girls. This study is a group (cluster) randomized trial, including 24 schools, pair matched and assigned to intervention (n = 12) or control (n = 12) conditions. Participants included 1,519 girls in racially diverse public schools in urban, underserved areas of the Midwestern USA. The intervention included three components: (i) 90-min after-school physical activity (PA) club offered 3 days/week; (ii) two motivational, individually tailored counseling sessions; and (iii) an interactive Internet-based session at the midpoint of the intervention. Main outcome measures were weighted mean minutes of MVPA per week post-intervention and at 9-month follow-up measured via accelerometer. No between-group differences occurred for weighted mean minutes of MVPA per week at post-intervention (B = -0.08, p = .207) or 9-month follow-up (B = -0.09, p = .118) while controlling for baseline MVPA. Research is needed to identify interventions that assist girls in attaining and maintaining adequate PA. NCT01503333.

A longitudinal study of urban moveability and physical activity in the transition phase from childhood to adolescence

Introduction Physical activity (PA) is one of the most important lifestyle behaviors to reduce the risk for non-communicable diseases. Positive effects of the urban environment on PA in terms of walkability measures such as street connectivity, land use mix, and availability of public open spaces in the urban neighborhood are well investigated. However, evidence of this association is mostly based on cross-sectional studies. Usually, discrete measures of urban point characteristics such as the simple intensity are calculated based on arbitrary municipal districts inducing scaling bias. The present study aims to longitudinally investigate the effect of built environment characteristics on PA of children in their transition phase to adolescence. We considered a kernel intensity approach to assess built environment characteristics and linked urban measures with objectively measured PA data that were collected in the IDEFICS/I.Family cohort. Methods Spatial data were collected in six study regions of three countries, Germany, Italy, and Sweden, participating in the IDEFICS/I.Family cohort. We considered walkability measures such as population density, land use mix (LUM), street connectivity, and availability of public transit. We additionally assessed the availability of public open spaces (POS). Point characteristics, e.g. intersections or POS, were assessed via adaptive anisotropic kernel functions. Urban measures were calculated in network-dependent home neighborhoods using a network distance of 1 km. We used standardized z-scores of urban measures to construct a moveability index that quantifies urban opportunities for PA of children and adolescents. Based on the place of residence, we linked urban measures with individual-level data of 699 children aged 2 to 14, who provided at least two (n = 610) or three (n = 89) accelerometer measurements, from either baseline, first follow-up (IDEFICS study), or second follow-up (I.Family study) with in total 1487 observations. Trajectories of moderate-to-vigorous physical activity (MVPA) as well as light physical activity (LPA) were modelled using linear mixed models accounting for repeated measurements nested within individuals by means of a random intercept and random linear slope for age (centred at 8 years). Environmental variables (z-scores) were included as fixed effects and as interaction effect with age. All models were stratified by sex and adjusted for age, BMI z-score, parental education, valid wear time, season, and region. Results Mean age was 6.6 in boys and 6.8 in girls. Compared to boys, girls spent on average less minutes in MVPA (boys: 58.8, girls: 51.6) and LPA (boys: 305, girls: 294) per day. Linear trajectories showed a significant decline of MVPA over age (boys: = −2.9, 95%CI: [−3.5; − 2.3], girls: = −3.6, [4.1; − 3.0]) and LPA (boys: = −7.6, [−9.1; − 6.1], girls: = −7.6, [−9.1; − 6.1]). The moveability index interacting with age showed only small effects on PA trajectories that were more pronounced for MVPA in boys (= 0.08, [−0.08;0.24]) and for LPA in girls (= 0.15, [−0.23;0.50]). Considering POS a stronger interaction with age was found for MVPA in boys (= 0.24, [−0.30; 0.78]) than in girls (= −0.08, [−0.58; 0.42]). The interaction of population density with age showed a positive effect on MVPA in boys, but not in girls, while the effect on LPA was stronger in girls compared to boys. Only in Girls, negative effects were found for LUM on MVPA (= −0.22, [−0.76; 0.33]) and LPA (= −1.14, [−2.52; 0.23]). Conclusion The kernel approach allowed for a flexible modelling of urban measures and improved the assessment compared to simple density methods. Although PA strongly declined with age, urban measures showed a supportive effect that attenuated this decline in the transition phase from childhood to adolescence. However, urban measures differently affected PA in boys and girls.

Associations of self-reported physical activity and depression in 10,000 Irish adults across harmonised datasets: a DEDIPAC-study

BackgroundDepression is a prevalent, debilitating, and often recurrent mood disorder for which successful first-line treatments remains limited. The purpose of this study was to investigate the cross-sectional associations between self-reported physical activity (PA) and depressive symptoms and status among Irish adults, using two existing datasets, The Irish Longitudinal Study on Ageing (TILDA) and The Mitchelstown Cohort Study.MethodsThe two selected databases were pooled (n = 10,122), and relevant variables were harmonized. PA was measured using the short form International Physical Activity Questionnaire. Depressive symptoms were measured by the Center for Epidemiologic Studies Depression (CES-D) questionnaire. Participants were classified as meeting World Health Organization moderate-to-vigorous PA (MVPA) guidelines or not, and divided into tertiles based on weekly minutes of MVPA. A CES-D score of ≥16 indicated elevated depressive symptoms. Data collection were conducted in 2010–2011.ResultsSignificantly higher depressive symptoms were reported by females (7.11 ± 7.87) than males (5.74 ± 6.86; p < 0.001). Following adjustment for age, sex, BMI, and dataset, meeting the PA guidelines was associated with 44.7% (95%CI: 35.0 to 52.9; p < 0.001) lower odds of elevated depressive symptoms. Compared to the low PA tertile, the middle and high PA tertiles were associated with 25.2% (95%CI: 8.7 to 38.6; p < 0.01) and 50.8% (95%CI: 40.7 to 59.2; p < 0.001) lower odds of elevated depressive symptoms, respectively.ConclusionMeeting the PA guidelines is associated with lower odds of elevated depressive symptoms, and increased volumes of MVPA are associated with lower odds of elevated depressive symptoms.

An Intervention to Increase Students’ Physical Activity: A 2-Year Pilot Study

Schools are called upon to provide children with 30 minutes/day of moderate to vigorous physical activity (MVPA). Most school-based physical activity interventions have not targeted schools that serve children from low-income families. This study evaluated the effects of a pilot, competency-building professional development program on the school day MVPA and total activity (light- to vigorous-intensity activity) of students from schools that serve low-income families. Single group intervention with multiple follow-up repeated cross-sectional measures. Students attending eight elementary schools in one low-income school district serving 3,719 students. Participatory-based, experiential, competency-building professional development workshop for physical education and classroom teachers. Baseline was fall 2015, and the intervention was delivered during spring 2016 through spring 2017. Hip-placed accelerometers were used to derive the percentage of children accumulating 30 minutes of MVPA during the school day, minutes of MVPA, and time spent sedentary. Analyses were conducted during July 2017. A total of 1,570 first- and fourth-grade students (49.8% girls, 87.0% African American, 88% free and reduced-price lunch) were measured across the project. Primary analyses indicated that the percentage of girls and boys meeting the 30-minutes/day guideline increased by 9.3% (95% CI=4.7%, 13.9%) and 10.4% (95% CI=5.5%, 15.3%), respectively. A corresponding increase of 1.7 (95% CI=0.5, 2.8) and 2.5 (95% CI=1.1, 3.8) MVPA minutes accumulated during the school day were observed for both girls and boys, respectively. Primary analyses indicated that statistically significant increases in MVPA and total activity for boys and girls were observed across the school day, during classroom time, and during physical education. Participatory-based, experiential, competency-building professional development is an effective strategy for increasing students' MVPA and total activity in low-income schools. However, data from this study indicate that targeting settings outside of the school day may be more appropriate given that schools were providing more than two thirds of the recommended 30 minutes/day of MVPA prior to intervention.