Validity and reproducibility of motion sensors in youth: a systematic update

Long-Term Impact of Physical Activity on Mortality in Adults With Multimorbidity: A 12-Year Cohort Longitudinal Study From the Survey on Health, Ageing and Retirement in Europe

BACKGROUND

While physical activity (PA) is known to reduce mortality in the general population, this relationship in individuals with multimorbidity (≥ 2 chronic conditions) is unclear. This longitudinal study aimed to investigate whether there is a long-term association between PA levels and mortality rates over a 12-year period in adults with multimorbidity.

METHODS

Data were obtained from eight waves of the Survey of Health, Ageing and Retirement in Europe (SHARE), from 28 European countries. PA levels were self-reported via computer-assisted personal interviews. Mortality during the follow-up period was assessed using data obtained from caregivers through end-of-life interview. Multimorbidity was identified based on the presence of two or more 15 self-reported chronic diseases/conditions. Cox's regression analysis, adjusted for potential confounders, was used to assess the association between PA level and mortality. p-values were calculated using the Jonckheere-Terpstra test for continuous variables and the Mantel-Haenszel Chi-square test for categorical variables, stratified by PA level.

RESULTS

The study included 9216 participants with multimorbidity (mean age 69 ± 10.1 years; 58.7% were women). Among those with multimorbidity, individuals with high PA level were significantly younger, more frequently men, less impaired in activities of daily living, less educated and less frequently obese than those with very low level of PA (p < 0.0001 for all comparisons). Over the 12 years of follow-up, mortality incidence was three times higher in individuals with multimorbidity and very low PA levels than those with multimorbidity and high levels of PA. After adjusting for confounders, the risk of mortality was significantly lower for participants with moderately low PA levels (HR = 0.64; 95% CI: 0.59-0.71; p < 0.0001), moderately high PA levels (HR = 0.53; 95% CI: 0.47-0.60; p < 0.0001) and high PA levels (HR = 0.49; 95% CI: 0.43-0.55; p < 0.0001) compared to those with very low PA levels.

CONCLUSIONS

Findings from the present study suggest that people with multimorbidity who had lower levels of PA were three times more likely to die prematurely after 12 years than adults with multimorbidity and higher levels of PA at baseline. These findings underscore the importance of promoting physical activity in adults with multimorbidity to reduce the risk of premature mortality. Future longitudinal research is required to confirm/refute our findings. Further, intervention studies are needed to understand whether increasing levels of physical activity in this population subsequently reduces mortality risk.

Comparison of community ambulation intensity determined from overground and treadmill walking cadence cut points: Is there a relationship between step activity measures and predicted VO2 max in healthy children and adults?

BACKGROUND

This study was designed to evaluate the effect of using maximal cadence criteria cut points established during overground and treadmill walking, on intensity outputs measured during community ambulation. The second aim was to establish the relationship between cardiovascular fitness (predicted VO2 max capacity) and community ambulation intensity performance, in typically developing individuals.

RESEARCH QUESTION

What is the effect on intensity measures when using cadence cut point criteria derived from overground and treadmill walking and does predicted VO2 max correlate with exercise related community activity in a typically developing population?

METHODS

A group of 37 typically developing participants between 8 and 27 years of age, underwent a graded submaximal VO2 testing protocol followed by a typical week of community ambulation, recorded with a step activity monitor. Maximum cadence criteria established during overground and treadmill walking were applied and the data were compared. The weekly step activity variables included: total steps, total ambulatory time, intensity, duration, and volume. Predicted VO2 Max was calculated, and correlations calculated to step activity outputs.

RESULTS

Results showed significant differences (p<0.001) between cadence cut point criteria across all intensity measures except in the amount of time spent in the 30-60 % intensity category (p=0.182). Predicted VO2 max did not significantly correlate with step activity outputs related to exercise (moderate+ intensity and long duration ambulatory bouts; p>0.277).

SIGNIFICANCE

This study illustrates the importance of close consideration in applying recommended cut off criteria when assessing intensity outputs from step activity data. Cadence from both overground and treadmill walking were collected in a controlled lab setting, but the influence of the treadmill mechanical and forced cadence criteria must be considered when selecting intensity cut points.

Investigating the association between self-reported physical function, temporo-spatial parameters, walking kinematics and community-based ambulatory activity: Analysis of post-operative hip preservation patients

INTRODUCTION

Wearable sensors provide the ability to assess ambulatory activity in the community after hip preservation surgery (HPS). In combination with gait analysis and patient reported outcomes, more perspective on post-operative function is gained. The purpose of this study was to assess the relationship between self-reported function/activity, temporo-spatial parameters and walking kinematics to objectively measured ambulatory activity.

METHODS

Forty-nine participants (38 Females; age range 16-38 years) who were five years or more post-surgery and the following diagnoses were included: Acetabular Dysplasia (n=34), Femoroacetabular Impingement (n=12) and Legg-Calvé Perthes disease (n=3). Participants underwent 3D gait analysis and gait deviations were quantified using the Gait Deviation Index (GDI) and Gait Profile Score (GPS). Temporo-spatial parameters were also calculated. Self-reported pain/function and activity level were assessed via the Harris Hip Score (HHS) and UCLA Activity Scale (UCLA). Participants wore a StepWatch Activity Monitor in their community and the Intensity/Duration of ambulatory bouts were analyzed. Spearman correlation coefficients were run to assess the following relationships: in-lab walking measures, self-reported function/activity vs.community ambulatory activity.

RESULTS

There were no statistically significant correlations between HHS, UCLA or temporospatial parameters with ambulatory activity (p>0.05). Worsening gait deviations (GDI/GPS scores) correlated with daily total ambulatory time (ρ=0.284/-0.284, p<0.05), time spent in Short duration ambulatory bouts (ρ=-0.321/0.321, p<0.05) and the amount of time in Long duration ambulatory bouts (ρ=0.366/-0.366, p<0.05). The amount of time spent in Easy intensity/Short duration and Easy intensity/Long duration ambulatory bouts did have a weak correlation with the GDI and GPS (p<0.05).

CONCLUSIONS

In HPS patients after long-term follow up, ambulatory activity in the community did not correlate with patient reported outcomes but there was a weak correlation with the presence of gait deviations. Incorporating wearable sensors to assess community ambulatory bout intensity/duration, provides additional quantifiable measures into the overall function of patients following HPS.

Comparison of three device generations of the StepWatch Activity Monitor: analysis of model version agreement in pediatric and adult independent ambulators

Purpose

Devices such as the StepWatch Activity Monitor (SAM) have been available for 20 years and have been shown to accurately measure ambulatory activity. This study aimed to evaluate the agreement among the three generations of the StepWatch Activity Monitor (SW3, SW4, and SW5) with respect to stride count.

Methods

A total of 36 participants (age range, 6-55 years) participated in this institutional review board-approved study. The participants concurrently wore three different SAM model devices on the same leg and performed a 6-min walk test (6MWT). A research staff member of the laboratory manually counted the number of strides for the first 2 min of the test (2MWT). Agreement among the device models was evaluated by calculating ANOVAs and interclass correlation coefficients (ICCs) and creating Bland-Altman plots.

Results

There was no significant difference among the model versions during the 6MWT and 2MWT (p > 0.05). The ICC for the total stride count was 0.993 (95% CI = 0.988-0.996) during the 2MWT and 0.992 (95% CI = 0.986-0.996) during the 6MWT. There was a near-perfect agreement (ICC ≥ 0.990) of each model version to the manually counted strides during the 2MWT. The systematic bias of all three SAM model versions was <1 step.

Conclusions

The results from the present study demonstrate that the stride counts among all three devices are comparable and relative to the manual stride count. All three SAM model versions had an ICC of >0.90. Researchers can safely incorporate historical data from previous SAM model versions with newer data collected with the latest SAM model version.

Effects of a staff-led multicomponent physical activity intervention on preschooler's fundamental motor skills and physical fitness: The ACTNOW cluster-randomized controlled trial

BACKGROUND

Fundamental motor skills (FMS) and physical fitness (FIT) play important roles in child development and provide a foundation for lifelong participation in physical activity (PA). Unfortunately, many children have suboptimal levels of PA, FMS, and FIT. The Active Learning Norwegian Preschool(er)s (ACTNOW) study investigated the effects of a staff-led PA intervention on FMS, FIT, and PA in 3-5-year-old children.

METHODS

Preschools in Western Norway having ≥ six 3-4-year-old children were invited (n = 56). Of these, 46 agreed to participate and were cluster-randomized into an intervention (n = 23 preschools [381 children, 3.8 yrs., 55% boys]) or a control group (n = 23 [438, 3.7 yrs., 52% boys]). Intervention preschools participated in an 18-month PA intervention involving a 7-month staff professional development between 2019 and 2022, amounting to 50 h, including face-to-face seminars, webinars, and digital lectures. Primary outcomes in ACTNOW were cognition variables, whereas this study investigated effects on secondary outcomes. FMS was measured through 9 items covering locomotor, object control, and balance skills. FIT was assessed as motor fitness (4 × 10 shuttle-run test) and upper and lower muscular strength (handgrip and standing long jump). PA was measured with accelerometers (ActiGraph GT3X +). All measures took place at baseline, 7-, and 18-month follow-up. Effects were analysed using a repeated measures linear mixed model with child and preschool as random effects and with adjustment for baseline scores.

RESULTS

Participants in the intervention preschools showed positive, significant effects for object control skills at 7 months (standardized effect size (ES) = 0.17) and locomotor skills at 18 months (ES = 0.21) relative to controls. A negative effect was found for handgrip strength (ES = -0.16) at 7 months. No effects were found for balance skills, standing long jump, or motor fitness. During preschool hours, sedentary time decreased (ES = -0.18), and light (ES = 0.14) and moderate-to-vigorous PA (ES = 0.16) increased at 7 months, whereas light PA decreased at 18 months (ES = -0.15), for intervention vs control. No effects were found for other intensities or full day PA.

CONCLUSIONS

The ACTNOW intervention improved some FMS outcomes and increased PA short-term. Further research is needed to investigate how to improve effectiveness of staff-led PA interventions and achieve sustainable improvements in children's PA, FMS, and FIT.

TRIAL REGISTRATION

Clinicaltrials.gov, identifier NCT04048967 , registered August 7, 2019.

FUNDING

ACTNOW was supported by the Research Council of Norway (grant number 287903), the County Governor of Sogn og Fjordane, the Sparebanken Sogn og Fjordane Foundation, and the Western Norway University of Applied Sciences.

Before-school physical activity patterns among adolescents using accelerometer and GPS data

Most adolescents do not meet physical activity (PA) guidelines. The before-school segment has been identified as one promising opportunity for intervention; however, there is a need for contextual understanding of PA in this segment. This study aimed to examine: a) adolescents' PA levels across various locations before school (6:00am - school start), b) contributions of before-school PA to daily PA and PA guidelines, and c) correlates of location-specific before-school PA. A cross-sectional analysis was conducted using adolescents' (n = 148, mean age 14.7) accelerometer and GPS data. Adolescents averaged 9.7 min in before-school moderate-to-vigorous PA (MVPA), representing substantial contributions to daily activity. Most MVPA occurred away from home and school. Significant correlates included segment duration, age, socio-economic status, and PA self-efficacy. Future work should consider these patterns and correlates to support adolescents' PA through targeted interventions.

Comparison of habitual physical activity in French Bulldogs, Pugs and normocephalic dogs by accelerometry

Brachycephalic obstructive airway syndrome (BOAS) is a major welfare concern in flat-faced dog breeds. As BOAS causes respiratory difficulties and exercise intolerance, it can reduce dogs' daily quality of life (QOL). However, evaluation of QOL in dogs is difficult, and many owners perceive BOAS signs as 'normal' for the breed. Accelerometers that measure frequency, duration and intensity of activities can offer an objective way of evaluating dogs' daily activity and thereby deliver potential insights into QOL. The aim of this study was to assess habitual physical activity of 48 brachycephalic and 23 non-brachycephalic dogs using accelerometers. The accelerometers were used for one week and owners filled in a questionnaire regarding their dog's well-being and activities. Veterinary-assessed BOAS grading for brachycephalic dogs was determined. Compared with controls, more severely affected French Bulldogs and Pugs had significantly lower total activity counts and spent less time in high activity. In Pugs, mildly affected dogs were also less active, but age can be a contributing factor here, as older age decreased activity in Pugs and controls showed a wider age range. In French Bulldogs, those dogs with no or mild signs of BOAS did not differ from controls regarding their daily activity. In conclusion, accelerometers were easy to use for objective measurement of daily activity in bracycephalic dogs, although a degree of discomfort due to the collar was reported. Results showed that BOAS signs were associated with decreased habitual physical activity. These findings emphasise the importance of actions taken to reduce incidence of BOAS in brachycephalic breeds.

Multivariate physical activity association patterns for fundamental motor skills and physical fitness in preschool children aged 3-5 years

Physical activity (PA) is important for children's development of fundamental motor skills (FMS) and physical fitness (FIT) but evidence regarding which intensities are associated with these outcomes in early childhood is limited. The aim of this study was to determine the cross-sectional multivariate PA intensity signatures associated with FMS and FIT in children aged 3-5 years. We used a sample of 952 Norwegian preschoolers (4.3 years, 51% boys) who provided data on PA (ActiGraph GT3X+), at least one FMS (locomotor, object control and/or balance skills) or FIT (speed agility, standing long jump, and/or handgrip strength) outcome, body mass index, and socioeconomic status in 2019-2020. We created 17 PA intensity variables (0-99 to ≥15000 counts per minute) from the vertical axis and used multivariate pattern analysis for analyses. The PA intensity spectrum (including sedentary time) was significantly associated with all outcomes. Associations for PA intensities were positive (negative for sedentary time), strongest for moderate and vigorous intensities, and were significant across sex and age groups. Our findings show that the PA intensity spectrum is associated with FMS and FIT in young children and that promotion of PA, in particular moderate- and vigorous-intensity activity, from an early age benefits children's physical development.

The role of TLR2 in exercise-induced immunomodulation in normal weight individuals

Toll-like receptors (TLRs) have been targeted for therapeutic drug development for several disorders, including cardiovascular diseases (CVD), and diabetes mellitus. Daily levels physical activity (PA) has been purported to influence the systemic circulation of cytokines, affecting the overall activation of TLRs and influencing the inflammatory milieu. Objective and self-reported daily PA was tracked in 69 normal-weight adults. Freedson's cut-offs categorized daily PA intensity into the 25th lowest, medium, and top percentiles. Monocytic TLR2 expression was quantified by flow cytometry in fresh whole blood. Cross-sectional associations between flow cytometry measured TLR2⁺ subsets and clinical biomarkers were evaluated. PA increased circulation of TLR2⁺ monocytes. TLR2 expression was adversely corelated with reduced diastolic blood pressure (DBP), triglyceride (TG), and matrix metallopeptidase 9 (MMP9) levels. However, regression analysis indicated that only TG levels were independently linked with TLR2⁺ subsets in circulation in active participants. Higher daily levels of physical activity are associated with improved cardiovascular blood markers and elevated circulatory monocytic TLR2⁺ subsets. These findings suggest that TLR2 may play a role in modulating CVD risk factors in individuals leading physically active lifestyles.

Schooltime's contribution to pupils' physical activity levels: A longitudinal study

Introduction

Pupils spend a significant portion of their time at school. As a result, the school serves as an important setting for both learning and the formation of healthy behaviors. Many children, and even fewer young people, do not fulfill the (inter)national health recommendations of 60 minutes of moderate to vigorous physical activity (MVPA) per day. The aim of this study was to examine pupils' MVPA during schooltime in a longitudinal perspective, including the transition from primary to secondary school.

Methods

The MVPA of 234 pupils' was measured objectively using accelerometer monitors for seven consecutive days, in the spring of 2017, 2018, and 2019. Statistical analyses by Friedman, Wilcoxon and Mann-Whitney U-test were used to answer the research questions.

Results

The results showed a significant decrease in the pupils' MVPA and fulfilment of health recommendations during schooltime, from 7^th to 8^th grade. The analyses also showed that MVPA during schooltime was higher among boys than girls, and also contributed more to boys' fulfilment of the health recommendations at all three time periods.

Discussion

The results indicate that the transition between primary and secondary school is vulnerable concerning pupils' MVPA during schooltime. As schooltime accounted for significantly more MVPA for boys than for girls at all three time periods, we question whether physical activity is sufficiently facilitated for girls in school.

Association Between Patient Factors and the Effectiveness of Wearable Trackers at Increasing the Number of Steps per Day Among Adults With Cardiometabolic Conditions: Meta-analysis of Individual Patient Data From Randomized Controlled Trials

BACKGROUND

Current evidence supports the use of wearable trackers by people with cardiometabolic conditions. However, as the health benefits are small and confounded by heterogeneity, there remains uncertainty as to which patient groups are most helped by wearable trackers.

OBJECTIVE

This study examined the effects of wearable trackers in patients with cardiometabolic conditions to identify subgroups of patients who most benefited and to understand interventional differences.

METHODS

We obtained individual participant data from randomized controlled trials of wearable trackers that were conducted before December 2020 and measured steps per day as the primary outcome in participants with cardiometabolic conditions including diabetes, overweight or obesity, and cardiovascular disease. We used statistical models to account for clustering of participants within trials and heterogeneity across trials to estimate mean differences with the 95% CI.

RESULTS

Individual participant data were obtained from 9 of 25 eligible randomized controlled trials, which included 1481 of 3178 (47%) total participants. The wearable trackers revealed that over the median duration of 12 weeks, steps per day increased by 1656 (95% CI 918-2395), a significant change. Greater increases in steps per day from interventions using wearable trackers were observed in men (interaction coefficient -668, 95% CI -1157 to -180), patients in age categories over 50 years (50-59 years: interaction coefficient 1175, 95% CI 377-1973; 60-69 years: interaction coefficient 981, 95% CI 222-1740; 70-90 years: interaction coefficient 1060, 95% CI 200-1920), White patients (interaction coefficient 995, 95% CI 360-1631), and patients with fewer comorbidities (interaction coefficient -517, 95% CI -1188 to -11) compared to women, those aged below 50, non-White patients, and patients with multimorbidity. In terms of interventional differences, only face-to-face delivery of the tracker impacted the effectiveness of the interventions by increasing steps per day.

CONCLUSIONS

In patients with cardiometabolic conditions, interventions using wearable trackers to improve steps per day mostly benefited older White men without multimorbidity.

TRIAL REGISTRATION

PROSPERO CRD42019143012; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=143012.

Risk and Resilience Predictors of Recovery After Spinal Fusion Surgery in Adolescents

OBJECTIVE

This prospective study examined risk and resilience predictors of pain and functional recovery in the first 6 months after spinal fusion surgery in adolescents.

METHODS

Adolescents with adolescent idiopathic scoliosis undergoing spinal fusion surgery (n=100, aged 12 to 18 y, 77% girls) completed assessments before surgery and at 3 weeks, 6 weeks, and 6 months after surgery. Recovery trajectories in pain, health-related quality of life (HRQOL), and objectively registered physical activity were identified. Presurgical pain catastrophizing and pain intensity (risk), and psychological flexibility, and postsurgical pain acceptance (resilience) were examined as predictors of recovery.

RESULTS

Latent growth class analyses revealed 4 distinct pain recovery trajectories (ie, Severe-Moderate [11%, n=9], Mild-No [58%, n=49], Moderate-Mild [24%, n=20], and Moderate-Severe [7%, n=6] pain trajectory), 2 HRQOL recovery trajectories; 2 trajectories characterizing recovery in average daily physical activity at moderate-to-vigorous intensity (MVPA); and 3 trajectories characterizing recovery in total physical activity volume characterized by the average daily number of steps. Subsequent multivariate analyses of variance revealed that presurgical pain intensity (partial η2=0.21, P<0.001) and pain catastrophizing (partial η2=0.13, P<0.01) were both predictive of poorer recovery in HRQOL, and pain catastrophizing additionally predicted poorer pain recovery (partial η2=0.15, P<0.05). Psychological flexibility (partial η2=0.25, P<0.001) and postsurgical pain acceptance (partial η2=0.07, P<0.05) were predictive of more favorable recovery trajectories in HRQOL, and psychological flexibility additionally predicted more favorable recovery trajectories in postsurgical pain (partial η2=0.15, P<0.05). Daily MVPA trajectories were not significantly predicted by any of the hypothesized factors, while presurgical pain catastrophizing levels were predictive of a delayed recovery trajectory in the daily amount of steps (partial η2=0.17 P<0.01).

CONCLUSIONS

Presurgical screening could include assessment of pain intensity, pain catastrophizing, psychological flexibility, and pain acceptance to identify adolescents who are at risk for poorer recovery. These are potentially modifiable factors that can be targeted in presurgical interventions to prevent poor and foster adaptive outcomes after major surgery in adolescents.

Can the training regimen influence night time physical activity in racehorses?

Physical activity has been widely investigated in horses to elucidate locomotion characteristics and behavior. However, research in real environment of training stables is limited. The objective of this study was to evaluate the effect of training regimen on night time physical activity of racehorses. Physical activities of twenty animals were monitored during the night time using accelerometers. The animals were compared in terms of training regimen: horses subjected to training on continual days, and horses subjected to training on intermittent days; age and sex were also considered. The variables analyzed were: counts per minute, percentage of time in (sedentary, light, moderate and vigorous) physical activity. Statistical analysis was performed by the PROCGLM procedure (ANOVA) and the means were calculated by Tukey's test. The training regimen impacts the physical activity of thoroughbreds. The mean counts per minute showed a higher physical activity in the intermittent trained animals in relation with continuously trained animals. The continuously trained animals presented a greater percentage of time in sedentary physical activity than those intermittent trained. However, intermittently trained horses spent a larger percentage of time in moderate and vigorous physical activity, in comparison with continuously trained animals. In conclusion, racehorses subject to training on continual days have lower physical activity in the night time than those that train on intermittent days.

The Effect of Strip Grazing on Physical Activity and Behavior in Ponies

This work aimed to determine the effect of strip grazing on physical activity in ponies using behavioral observations alongside accelerometers positioned at the poll. In study one, ten British native breed ponies were randomly assigned to paddock A (50 × 110 m) or B (50 × 110 m divided into seven equal strips with access to one additional strip per day) for seven days (n = 5/paddock). In study two, ten different British native breed ponies were randomly assigned for 14 days individually to (1) a control field where the animal was allowed complete access to their allotted area (n = 4); (2) a field that increased in size daily by moving a lead fence (n = 2); and (3) a field that was strip grazed using lead and back fences moved the same distance daily (n = 4). Accelerometer data were sorted into twenty-four-hour periods; each 10-second epoch was categorized as standing, grazing or locomoting using previously validated cut-off points; and time spent in each category for each day calculated. Behavioral monitoring was undertaken by direct observation on days 12-14 (study two only). Accelerometer and behavioral data were compared between grazing methods within each study. Strip grazing had no significant effect on the time spent in each physical activity category in either study. Behavioral observation revealed all ponies spent most time grazing ≤4 hours after fence moving and strip grazed ponies spent significantly more time grazing the newly available grass than elsewhere. Thus, strip grazing did not alter physical activity in ponies, but did result in preferential grazing of new grass.

Daily Physical Activity in Children and Adolescents with Low Lumbar and Sacral Level Myelomeningocele

PURPOSE

Children with low lumbar and sacral level myelomeningocele are expected to be community ambulators. However, they do not always meet the expected ambulation level by the time they reach adulthood. The purpose of this study is to investigate daily activity energy expenditure and physical activity levels of these patients in daily routine.

MATERIALS AND METHODS

20 patients and 20 healthy peers were included in this case-control study. Omnidirectional accelerometer monitor was used for assessing activity energy expenditure, and daily durations spent in sedentary, light activity, and moderate to vigorous physical activity levels (NCT04186338).

RESULTS

Mean activity energy expenditure and moderate to vigorous physical activity duration were significantly lower in the patient group, while age was positively correlated with sedentary time and negatively correlated with light activity time.

CONCLUSIONS

In patients with myelomeningocele, increasing daily activity energy expenditure and moderate to vigorous physical activity and, especially as age progresses, decreasing the sedentary behavior may assist in providing the expected ambulation level. These patients should be encouraged to partake in regular exercise programs.

A 20-Year Follow-Up Study of Objectively Measured Physical Activity

BACKGROUND

The objectives of this study were to explore the effect of time, long-term tracking, and the proportion of objectively measured physical activity (PA) from early adolescence to the mid-thirties.

METHODS

PA was measured as mean steps per day (SPD) with pedometers during 2000 (T1), 2003 (T2), 2005 (T3), 2010 (T4), 2016 (T5) and 2020 (T6). Data from 64 participants (n = 32 males) were analysed from their early adolescence (T1) to their mid-thirties (T6).

RESULTS

SPD decreased in the total sample and among males and females (all, p < 0.001). Males took more mean SPD than females during T1 (p = 0.002), whereas females took more mean SPD during T2 (p = 0.009) and T6 (p = 0.008). Males' mean SPD tracked between T1 and T2 (p = 0.021), T2 and T3 (p = 0.030), T3 and T4 (p = 0.015) and T4 and T5 (p = 0.003). Females' mean SPD tracked between T3 and T4 (p = 0.024) and T5 and T6 (p < 0.001). In the total sample, more mean SPD were found on weekdays compared to weekend days at T3 (p = 0.017) and T5 (p < 0.001).

CONCLUSIONS

SPD decreased between T1 and T6. Mean SPD tracked low-to-moderate in the short time span. From late adolescence to the mid-thirties, more mean SPD was observed during weekdays compared to weekend days.

A Standardized Buffalo Concussion Treadmill Test Following Sport-Related Concussion in Youth: Do ActiGraph Algorithms Matter?

CONTEXT

Current recovery guidelines following sport-related concussion (SRC) include 24-48 hours of rest followed by gradual return-to-activity with heart rate (HR) maintained below symptom threshold. Additionally, the monitoring of physical activity (PA) post-SRC using ActiGraph accelerometers can provide further objective insight on amounts of activity associated with recovery trajectories. Cut-point algorithms for these devices allow minute-by-minute PA to be classified into intensity domains; however, studies have shown different algorithms employed on the same healthy participant dataset can produce varying classifications.

OBJECTIVE

To identify the most physiologically appropriate cut-point algorithm (Evenson or Romanzini) to analyze ActiGraph data in concussed youth with comparisons to HR response on the Buffalo Concussion Treadmill Test (BCTT).

DESIGN

Prospective cohort study.

SETTING

Sport-concussion clinic within a university setting.

PATIENTS OR OTHER PARTICIPANTS

Eleven high-school students (5 male, 6 female; median [range] age =16 years [15-17], height = 177.8 cm [157.5-198.1], weight = 67 kg [52-98], body mass index = 22 kg/m2 [17-31]) involved in high-risk sport who sustained a physician diagnosed SRC.

MAIN OUTCOME MEASURE(S)

Evenson and Romanzini algorithm PA intensity domains via ActiGraph data and HR during the BCTT.

RESULTS

There were differences in moderate (P = .001) and vigorous (P = .002) intensities between algorithms, but no difference in light (P = .548). Evenson classified most of the time as moderate intensity (57.03% [0.00-94.12%]), whereas Romanzini classified virtually all PA as vigorous (88.25% [2.94-97.06%]). PA based on HR (stages 1-7: 20-39% HR reserve (HRR), stages 8-13: 40-59% HRR, stages 14 and above: 60-85% HRR) indicated the BCTT primarily involves light-to-moderate intensity, and therefore is better represented by the Evenson algorithm.

CONCLUSIONS

The Evenson algorithm better characterizes the HR response during a standardized exercise test in concussed individuals and therefore should be used to analyze ActiGraph PA data in a concussed paediatric population.

Adaptation and validation of the Physical Activity Questionnaire for Older Children (PAQ-C) among Czech children

The study aimed to adapt the standardized Physical Activity Questionnaire for Older Children (PAQ-C) into the Czech language and assess its psychometric properties. A forwards-and-backwards translation method was carried out to prepare the Czech PAQ-C version (PAQ-C/CZ), followed by adjustments based on socio-cultural aspects. In the next phase, participants (n = 169) wore accelerometers for seven days. On the 8th day, participants completed the PAQ-C/CZ in school so that it was possible to determine the concurrent validity (correlation between the accelerometer and PAQ-C/CZ data, Spearman’s r), internal consistency (Cronbach’s alpha), item/scale properties (corrected item-total correlations, CITCs), and factor structure (exploratory factor analysis, EFA) for PAQ-C/CZ. In the last phase, participants (n = 63) completed the PAQ-C/CZ twice on two consecutive school days in the morning to determine the test-retest reliability (intraclass correlation coefficient, ICC; independent sample T-test). The PAQ-C/CZ indicated moderate internal consistency (alpha = 0.77), acceptable item/scale properties (CITCs = 0.29–0.61), and good test-retest reliability (ICC = 0.73–0.94). The EFA findings suggested a single factor model (factor load = 0.32–0.73) for PAQ-C/CZ, with items 2, 3, and 4 contributing low to the total score. Results on concurrent validity showed low but significant association (r = 0.28, p < 0.05) between accelerometer and PAQ-C/CZ data. Considering the study results, the PAQ-C/CZ can be recommended as a tool for moderate-to-vigorous physical activity assessment in large-sample research studies only, but with an emphasis on the interpretation of the correct results.

Measurement Reactivity of Accelerometer-Based Sedentary Behavior and Physical Activity in 2 Assessment Periods

BACKGROUND

The purposes of this study were to examine accelerometer measurement reactivity (AMR) in sedentary behavior (SB), physical activity (PA), and accelerometer wear time in 2 measurement periods and to quantify AMR as a human-related source of bias for the reproducibility of SB and PA estimates.

METHODS

In total, 136 participants (65% women, mean age = 54.6 y) received 7-day accelerometry at the baseline and after 12 months. Latent growth models were used to identify AMR. Intraclass correlations were calculated to examine the reproducibility using 2-level mixed-effects linear regression analyses.

RESULTS

Within each 7-day accelerometry assessment, the participants increased their time spent in SB (b = 2.4 min/d; b = 3.8 min/d) and reduced their time spent in light PA (b = -2.0 min/d; b = -3.2 min/d), but did not change moderate to vigorous PA. The participants reduced their wear time (b = -5.2 min/d) only at the baseline. The intraclass correlations ranged from .42 for accelerometer wear time to .74 for SB. The AMR was not identified as a source of bias in any regression model.

CONCLUSIONS

AMR may influence SB and PA estimates differentially. Although 7-day accelerometry seems to be a reproducible measure, our findings highlight accelerometer wear time as a crucial confounder in analyzing SB and PA data.

Short Sleep Duration and Its Association with Obesity and Other Metabolic Risk Factors in Kuwaiti Urban Adults

BACKGROUND

Efficient sleep duration and its quality are increasingly recognized as important contributors for maintaining normal body weight. However, lifestyle and social structure within the Arab-gulf region differ compared to those in the western world. This study was specifically conducted in Kuwait's population to investigate the link between sleep quality (SQ) and obesity in the absence of sleep apnea (SA) onset.

METHODS

SQ was measured by the Pittsburgh Sleep Quality Index (PQSI) in 984 participants, then verified in 60 individuals including 20 lean (Body mass index/BMI: 18.5-24.9 kg/m²), 20 overweight (BMI: 25-29.9 kg/m²) and 20 obese (BMI: ≥30 kg/m²) through actigraph worn over the right-hip for 7 consecutive days to characterize their sleep-wake cycle, rest-activity, and physical activity. Blood samples were collected for metabolic markers.

RESULTS

59.6% of participants reported a PSQI score higher than 5, with 57.6% of the participants reporting less than 6 hours of sleep per day. The data show that both SQ and sleep duration are considered inadequate in comparison to the international SQ standards. We found a significant association between SQ and obesity independent of age and sex. Actigraph data further supported the independent association of sleep duration on BMI within the population (p < 0.001). Additionally, total sleep time (TST) was found to significantly correlate with several other metabolic factors including diastolic blood pressure, elevated resting heart rate (RHR), triglycerides, total cholesterol, homeostatic model assessment for insulin resistance (HOMA-IR), C-peptide, and C-Reactive Protein (CRP) secretion. Further multiple-regression analysis showed a significant independent association between blood pressure (p < 0.03), HOMA-IR (p < 0.04), and C-peptide (p < 0.3) and sleep duration.

CONCLUSION

These findings suggest that sleep deprivation and disturbance could be indirect factors involved in the development of not only obesity in Kuwait but also other metabolic syndromes such as type 2 diabetes.

No differences in physical activity between children with overweight and children of normal-weight

BACKGROUND

The aim of this study was to investigate the differences in objectively measured physical activity and in self-reported physical activity between overweight and normal-weight children.

METHODS

Data from a prospective cohort study including children, presenting at the participating general practices in the south-west of the Netherlands, were used. Children (aged 4-15 years) were categorized as normal-weight or overweight using age- and sex specific cut-off points. They wore an ActiGraph accelerometer for one week to register physical activity, and filled out a diary for one week about physical activity.

RESULTS

A total of 57 children were included in this study. Overweight children spent significantly less percentage time per day in sedentary behavior (β - 1.68 (95%CI -3.129, - 0.07)). There were no significant differences in percentage time per day spent in moderate to vigorous physical activity (β 0.33 (- 0.11, 0.78)). No significant differences were found between children of normal-weight and overweight in self-reported measures of physical activity.

CONCLUSIONS

Overweight children are not less physically active than normal-weight children, which may be associated with the risen awareness towards overweight/obesity and with implemented interventions for children with overweight/obesity.

Active Learning Norwegian Preschool(er)s (ACTNOW) - Design of a Cluster Randomized Controlled Trial of Staff Professional Development to Promote Physical Activity, Motor Skills, and Cognition in Preschoolers

INTRODUCTION

There is a dearth of high-quality evidence on effective, sustainable, and scalable interventions to increase physical activity (PA) and concomitant outcomes in preschoolers. Specifically, there is a need to better understand how the preschool context can be used to increase various types of physically active play to promote holistic child development. The implementation of such interventions requires highly competent preschool staffs, however, the competence in promoting PA is often low. The main aim of the ACTNOW study is therefore to investigate the effects of professional development for preschool staffs on child PA and developmental outcomes.

METHODS

The study will be conducted in Norway 2019-2022 and is designed as a two-arm (intervention, control) cluster randomized controlled trial (RCT) with 7- and 18-months follow-ups. We aim to recruit 60 preschools and 1,200 3- to 5-years-old children to provide sufficient power to detect effect sizes (ESs) between 0.20 and 0.30. The intervention is nested within two levels: the preschool and the child. Central to the ACTNOW intervention are opportunities for children to engage in a variety of "enriched," meaningful, and enjoyable physically active play that supports the development of the whole child. To this end, the main intervention is a 7-month professional development/education module for preschool staff, aimed to provide them with the necessary capacity to deliver four core PA components to the children (moderate-to-vigorous PA, motor-challenging PA, cognitively engaging play, and physically active learning). We will include a range of child-level outcomes, including PA, physical fitness, adiposity, motor skills, socioemotional health, self-regulation, executive function, and learning. At the preschool level, we will describe implementation and adaptation processes using quantitative and qualitative data.

DISCUSSION

Professional development of staff and a whole-child approach that integrates PA with cognitively engaging play and learning activities in the preschool setting may provide a feasible vehicle to enhance both physical and cognitive development in young children. ACTNOW is designed to test this hypothesis to provide a sustainable way to build human capital and provide an early solution to lifelong public health and developmental challenges.

CLINICAL TRIAL REGISTRATION

www.ClinicalTrials.gov identifier NCT04048967.

Review of Validity and Reliability of Garmin Activity Trackers

Purpose

A systematic review to summarize the validity and reliability of steps, distance, energy expenditure, speed, elevation, heart rate, and sleep assessed by Garmin activity trackers.

Methods

Searches included studies published through December 31, 2018. Correlation coefficients (CC) were assessed as low (<0.60), moderate (0.60-<0.75), good (0.75-<0.90), or excellent (>=0.90). Mean absolute percentage errors (MAPE) were assessed as acceptable at <5% in controlled conditions and <10% for free-living.

Results

Overall, 32 studies of adults documented validity. Four of these studies also documented reliability. The sample size ranged from 1 to 95 for validity and 4 to 31 for reliability testing. Step inter- and intra-reliability was good-to-excellent and speed intra-reliability was excellent. No other features were explored for reliability. Step validity, across 16 studies, generally indicated good-to-excellent CC and acceptable MAPE. Distance validity, tested in three studies, generally indicated poor CC and MAPE that exceeded acceptable limits, with both over and underestimation. Energy expenditure validity, across 12 studies, generally indicated wide variability in CC and MAPE that exceeded acceptable limits. Heart rate validity in five studies had low-to-excellent CC and all MAPE exceeded acceptable limits. Speed, elevation, and sleep validity were assessed in only one or two studies each; for sleep, the criterion relied on self-report rather than polysomnography.

Conclusion

This systematic review of Garmin activity trackers among adults indicated higher validity of steps; few studies on speed, elevation, and sleep; and lower validity for distance, energy expenditure, and heart rate. Intra- and inter-device feature reliability needs further testing.

Epidemiological Transition in Physical Activity and Sedentary Time in Children

BACKGROUND

To determine if children's moderate to vigorous physical activity (MVPA) and sedentary time varied across levels of household income in countries at different levels of Human Development Index (HDI), consistent with the theory of epidemiological transition.

METHODS

Data from 6548 children (55% girls) aged 9-11 years from 12 countries at different HDI levels are used in this analysis to assess MVPA and sedentary time (measured using ActiGraph accelerometers) across levels of household income. Least-square means are estimated separately for boys and girls at the estimated 10th, 50th, and 90th percentiles of HDI for the sample.

RESULTS

For boys, time in MVPA is negatively associated with income at the 10th and 50th percentiles of HDI (both P < .002). For girls, time in MVPA is negatively associated with income at the 10th and 50th percentiles of HDI (all P < .01) and positively related with income at the 90th percentile (P = .04). Sedentary time is positively associated with income at the 10th percentile of HDI for boys (P = .03), but not for girls.

CONCLUSIONS

Results support the possibility of an epidemiological transition in physical activity, with lower levels of MVPA observed at opposite levels of income depending on the HDI percentile. This phenomenon was not observed for sedentary time.

Increasing the Duration of Light Physical Activity Ameliorates Insulin Resistance Syndrome in Metabolically Healthy Obese Adults

Obesity is a well-known risk factor for insulin resistance syndrome (IRS). Nevertheless, limited data are available regarding the effects of physical activity (PA) intensity on the ability to modulate IRS. The study aim was to investigate the beneficial effects of the longer duration of light PA vs. a single bout of the acute moderate or vigorous PA for improvement in IRS indicators. Sixty metabolically healthy obese (MHO) participants, 30 males and 30 females, with body mass index (BMI) of ≥30 were enrolled in this study. PA levels were measured using an accelerometer, and the expression of monocytic surface markers was analyzed using flow cytometry. Plasma cytokines’ secretion was determined by enzyme-linked immunosorbent assay (ELISA). Univariate regression analysis evaluated the actigraphy-assessed PA measures, inflammatory cytokines, and insulin resistance. The longer duration of PA was found to be associated with the homeostatic model assessment of insulin resistance (HOMA-IR), a lower lipid profile, and the expression of inflammatory cytokines by monocytes. Even though, higher intensities of PA were found to be associated with lower body fat percentage, only the light intensity PA was found to be beneficial as it associated with the improved insulin sensitivity and lower expression of inflammatory markers. In conclusion, maintaining the longer duration of low-intensity PA throughout the day could be more beneficial for reducing inflammation and improving insulin resistance. This study supports a more feasible approach model to gain beneficial lifestyle changes for the prevention of IRS in metabolically healthy adults with obesity.

Residential vs school neighborhoods: Associations with physical activity among adolescents

Adolescents have the potential to be active in multiple places across weekdays and weekends. While the built environment features around home are known to be important for adolescents' physical activity, specific built environment features that facilitate physical activity outside the home neighbourhood are not well explored. Given that adolescents spend most days of the week at school, the built environment surrounding school may be particularly important for supporting their physical activity. This study examined cross-sectional associations of objective built environments around home and school at multiple spatial scales with accelerometer assessed moderate-to-vigorous physical activity (MVPA) across the week. Moderating effects of adolescents' age were further explored. Data from up to 417 adolescents aged 12-20 years from 18 schools in Melbourne, Australia were used. Features of the built environment around school were positively associated with MVPA on weekdays; and a wide range of built environment features around home were found to be important for MVPA during weekends. Age was found to moderate the relationship between some built environment features around both home and school and MVPA across the week. Understanding the contribution of the built environment features around both home and school with MVPA could inform policy recommendations and public health interventions for each setting.

School-based study showed a correlation between physical activity and smartphone and tablet use by students aged eight, 11 and 14

AIM

This study investigated correlations between objectively measured physical activity (PA) and smartphone and tablet usage by sex and age in subjects aged eight, 11 and 14.

METHODS

We recruited 549 children and adolescents (264 boys) from six schools in three middle-class communities in south-eastern Sweden. Steps per day were objectively measured using sealed pedometers and a brief daily questionnaire about smartphone and tablet usage. Correlations between mean steps per day and mean daily minutes of smartphone and tablet usage, and differences between low and high users, were investigated.

RESULTS

There was a moderately inverse correlation between steps per day and smartphone and tablet usage in the total sample (r = -.329, P < .001), but it was lower in boys (r = -.340, P < .001) than girls (r = -.401, P < .001). When stratified further by both sex and age, this correlation was only found among 14-year-old girls (r = -.385, P < .001) and this group only, differences between low and high users (P = .005) were seen.

CONCLUSION

There was a moderately inverse correlation between steps per day and smartphone and tablet usage. When stratified by both sex and age groups, this correlation was only observed in 14-year-old girls. The results may have implications for future PA interventions that target adolescent girls.

Environmental Mismatch: Do Associations between the Built Environment and Physical Activity among Youth Depend on Concordance with Perceptions?

Without accurate awareness of features within the built environment, the availability of a supportive built environment alone may not be sufficient to influence physical activity levels. We examined the moderating effects of concordance/discordance between selected objective and perceived built environment features in the relationship between objective built environment features and physical activity. Cross-sectional data from 465 youth aged 12–20 years from 18 schools in Melbourne, Australia were used. The relationship between trails and physical activity differed by concordance/discordance. There were positive relationships among those with concordant perceptions, but no significant differences for those with discordant perceptions. At least for trails, environmental interventions designed to enhance physical activity may be less effective if efforts are not made to enhance individuals’ awareness of their environment.

Infants' and toddlers' physical activity and sedentary time as measured by accelerometry: a systematic review and meta-analysis

BACKGROUND

Early experiences in physical activity (PA) are important to shape healthy movement behaviours long-term; as such, it is critical that PA is promoted from infancy, and that detrimental behaviours (e.g., prolonged sedentary time [ST]) are minimized. The purpose of this systematic review and meta-analysis was to examine infants' and toddlers' movement behaviours across daytime hours.

METHODS

Seven online databases were searched for terms related to infants (< 12 months), toddlers (12-35.9 months), PA, ST, and accelerometry. Two independent reviewers examined 4873 articles for peer-reviewed original research, published in English, that assessed infants' (counts/min) and/or toddlers' PA or ST (min/day) using accelerometry across daytime hours. Infants' mean PA level (counts/min) was averaged across studies, and ranges were produced. Estimates of toddlers' movement behaviours were aggregated meta-analytically to produce average daily rates, and accelerometer placement, cut-point validity, device type, and epoch length were tested as a moderating variables.

RESULTS

Twenty-four studies from 16 countries (published 2011-2019), representing 3699 participants, were included in the systematic review. Five studies reported on infants' PA, which ranged from 78.2 to 2580.5 cpm. Across 20 studies, toddlers' total PA, light PA, moderate-to vigorous-intensity PA, and ST ranged from 72.9 to 636.5, 48.5 to 582.4, 6.5 to 89.9, and 172.7 to 545.0 min/day, respectively. After taking into account accelerometer placement, cut-point validity, device type, and epoch length, we found that toddlers engaged in 246.19 min/day (SE = 28.50; 95% CI: 190.34, 302.04) of total PA, 194.10 min/day (SE = 28.76; 95% CI: 137.73, 250.47) of light PA, and 60.16 min/day (SE = 5.88; 95% CI: 48.64, 71.69) of moderate-to vigorous-intensity PA. Toddlers engaged in 337.04 min/day (SE = 32.67; 95% CI: 273.01, 401.07) of ST.

CONCLUSIONS

With limited studies conducted in infants (n = 5), PA estimates are inconclusive and largely heterogeneous. Overall, toddlers tend to exceed the total PA recommendation of 180 min/day; however, very little of this time is spent at higher movement intensities. Even with high PA rates, toddlers still engage in substantial ST. More consistent and valid measurement protocols are needed to improve comparability across studies.

Using accelerometry for measurement of motor behavior in children: Relationship of real-world movement to standardized evaluation

BACKGROUND

When detected, children with asymmetrical motor impairment are referred for therapeutic interventions to maximize the child's ability to reach their health and developmental potential. Referal is dependent on standardized evaluation, which rarely examines upper extremity (UE) function within the context of real-world activity. Accelerometry provides an efficient method to objectively measure movement in children. The purpose of this study was to compare accelerometry to clinical assessment, specifically the Melbourne Assessment of Unilateral Upper Limb Function-2 (MA-2).

METHODS

A total of 52 children between 1-17 years of age with asymmetrical motor deficits and age matched controls participated in this study. Participants wore bilateral accelerometers for 4 x 25 h. The use ratio (UR) and mono-arm use index (MAUI) were calculated to quantify asymmetrical impairment. The Melbourne Assessment of Unilateral Upper Limb Function-2 (MA-2) was administered and compared to accelerometry variables.

RESULTS

The UR and MAUI were significantly different in children with and without deficits. The MAUI was significantly correlated with all domains of the MA-2: accuracy (r = 0.44, p = 0.026); fluency (r = 0.52, p = 0.006); dexterity (r = 0.53, p = 0.005); and range of motion (r = 0.49, p = 0.011).

CONCLUSIONS

Our findings suggest a relationship between real-world movement and clinical evaluation.

Built environment and physical activity among adolescents: the moderating effects of neighborhood safety and social support

BACKGROUND

Increasing emphasis has been placed on improving physical activity levels through multilevel interventions. This study aims to examine moderating effects of neighborhood safety (crime and traffic) and social support (from parent and sibling/peer) for physical activity in the relationship between the built environment and moderate-to-vigorous physical activity (MVPA) outside school hours among adolescents in Melbourne.

METHODS

Data were from the NEighbourhood Activity in Youth study conducted among adolescents in Melbourne, Australia (n = 358, 15.3 (SD = 1.5) years). MVPA outside school hours was assessed by accelerometer. Built environment features within 1 km and 2 km residential buffers including recreation facilities, park area, and walkability and its components were assessed using Geographic Information Systems. Neighborhood safety, social support for physical activity and sociodemographic information were self-reported by adolescents. Multilevel linear regression models were used to estimate associations.

RESULTS

Support for physical activity from sibling/peer positively moderated the relationship between recreation facilities (1 km), residential density (2 km) and MVPA. Recreation facility (count within 2 km), walkability (1 km and 2 km) and residential density (1 km) had significant positive associations with MVPA outside school hours.

CONCLUSION

The built environment appeared to have stronger facilitating effects on MVPA among adolescents who had favourable support for physical activity from their sibling or peer. Multilevel interventions that target the built environment and social factors are needed to promote MVPA outside school hours among adolescents.

A peer-led physical activity intervention in schools for adolescent girls: a feasibility RCT

Background

Girls are less active than boys and few adolescent girls meet physical activity (PA) guidelines. Peers are an important influence on the views and behaviours of adolescent girls, yet many PA interventions involving peers use formal approaches that may not harness the power of peer groups. More informal peer-led PA interventions, which work within proximal peer groups, may hold promise for increasing girls’ PA.

Objectives

To examine the feasibility, evidence of promise and cost of the Peer-Led physical Activity iNtervention for Adolescent girls (PLAN-A), a peer-led PA intervention.

Design

Phase 1 comprised formative work and a pilot study conducted in one secondary school. Phase 2 was a feasibility study comprising a pilot randomised controlled trial in six secondary schools, including process and economic evaluations.

Setting

Six secondary schools in South Gloucestershire and Wiltshire, recruited from schools above the median local Pupil Premium (i.e. more deprived).

Participants

Year 8 girls (aged 12–13 years).

Intervention

Year 8 girls nominated other girls in their year who are likely to be influential (e.g. who they look up to, are good listeners); the 18% most nominated were invited to be peer supporters (PSs). PSs attended 2 consecutive days of training (plus a top-up day 5 weeks later) outside the school site, led by pairs of PS trainers, to increase their knowledge about PA and their capabilities and confidence to promote PA in their friendship group.

Main outcome measures

Measures focused on establishing evidence for feasibility and promise: recruitment and retention of Year 8 girls and PSs, data provision rates [accelerometer and questionnaire collected pre randomisation/beginning of Year 8 (T0), end of Year 8 (T1) and beginning of Year 9 (T2)], intervention acceptability, PS training attendance, intervention cost, and the between-arm difference in weekday minutes of moderate to vigorous PA (MVPA). A process evaluation was conducted.

Results

Six schools were recruited: four PLAN-A (n = 269) and two control (n = 158). In total, 94.7% of Year 8 girls participated. A total of 55 (17–24% of Year 8 girls) PSs were trained (attendance rate 91–100%). Five girls were trained as PS trainers. Questionnaire data provision exceeded 92% at all time points. Accelerometer return rates were > 85% and wear-time criteria were met by 83%, 71% and 62% of participants at T0, T1 and T2, respectively. Mean weekday MVPA did not differ between intervention arms at T1 (1.1 minutes, 95% CI –4.3 to 6.5 minutes) but did at T2 (6.1 minutes, 95% CI 1.4 to 10.8 minutes), favouring PLAN-A. The mean cost of intervention delivery was £2685 per school or £37 per Year 8 girl. Process evaluation identified good fidelity, engagement and enjoyment of the PS training and peer-support strategies. PSs needed more guidance on how to start conversations.

Limitations

Accelerometer data provision was lowest at T2, suggesting a need for strategies to increase compliance.

Conclusions

Informal peer-led intervention approaches, such as PLAN-A, hold promise as a means of promoting PA to adolescent girls.

Future work

A definitive randomised controlled trial of PLAN-A is warranted.

Trial registration

Current Controlled Trials ISRCTN12543546.

Funding

This project was funded by the National Institute for Health Research (NIHR) Public Health Research programme and will be published in full in Public Health Research; Vol. 7, No. 16. See the NIHR Journals Library website for further project information. The work was undertaken with the support of the Centre for the Development and Evaluation of Complex Interventions for Public Health Improvement (DECIPHer), a UK Clinical Research Collaboration (UKCRC) Public Health Research Centre of Excellence. Joint funding (MR/KO232331/1) from the British Heart Foundation, Cancer Research UK, Economic and Social Research Council, Medical Research Council, the Welsh Government and the Wellcome Trust, under the auspices of the UKCRC, is gratefully acknowledged. This study was designed and delivered in collaboration with the Bristol Randomised Trials Collaboration (BRTC), a UK CRC-registered clinical trials unit in receipt of NIHR clinical trials unit support funding. The intervention costs were jointly funded by South Gloucestershire Council and Wiltshire Council.

Critical Hours and Important Environments: Relationships between Afterschool Physical Activity and the Physical Environment Using GPS, GIS and Accelerometers in 10-12-Year-Old Children

Introduction: The objective of this study was to assess relationships between children’s physical environment and afterschool leisure time physical activity (PA) and active transport. Methods: Children aged 10–12 years participated in a 7-day accelerometer and Global Positioning Systems (GPS) protocol. Afterschool leisure time PA and active transport were identified based on location- and speed-algorithms based on accelerometer, GPS and Geospatial Information Systems (GIS) data. We operationalized children’s exposure to the environment by combining home, school and the daily transport environment in individualized daily activity-spaces. Results: In total, 255 children from 20 Dutch primary schools from suburban areas provided valid data. This study showed that greenspaces and smaller distances from the children’s home to school were associated with afterschool leisure time PA and walking. Greater distances between home and school, as well as pedestrian infrastructure were associated with increased cycling. Conclusion: We demonstrated associations between environments and afterschool PA within several behavioral contexts. Future studies are encouraged to target specific behavioral domains and to develop natural experiments based on interactions between several types of the environment, child characteristics and potential socio-cognitive processes.

Comparisons of pedometer-determined weekday physical activity among Swedish school children and adolescents in 2000 and 2017 showed the highest reductions in adolescents

AIM

This study compared differences in weekday physical activity among school children and adolescents in middle-class communities in south-eastern Sweden in 2000 and 2017.

METHODS

Data were drawn from two independent cross-sectional cohorts of children and adolescents aged 8, 11 and 14. The same six schools, protocols, procedures and instruments were used in both years, with 332 subjects in 2000 and 562 in 2017. Mean steps per day (SPD) were measured with a Yamax SW-200 pedometer.

RESULTS

The mean weekday SPD was similar among eight-year-old girls in both years, but 8% (p = 0.040) higher among eight-year-old boys in 2017. However, among 11-year-old children, the mean SPD were 12% lower among both girls (p = 0.033) and boys (p = 0.001). The SPD among 14-year-old adolescents were 24% (p = 0.012) and 30% (p < 0.001) lower among girls and boys, respectively.

CONCLUSION

This school-based study from south-eastern Sweden showed that weekday physical activity differed between age groups in 2000 and 2017. The highest reductions were seen among older children and adolescents, particularly 14-year-old girls and boys. The only group that increased was eight-year-old boys, with no significant change in eight-year-old girls. A possible explanation might be the dramatically increased use of the Internet on phones and tablets.

Objectively assessed vigorous physical activity and motor coordination are associated in 11-year old children

This cross-sectional study examined the associations between gender, sports club (SC) participation, physical activity (PA), motor coordination (MQ) and object control skill (TC). 11 year-old children (n = 477) wore accelerometers during seven consecutive days for the analysis of moderate PA (MPA) and vigorous PA (VPA). To detect motor competence (MC), children's motor coordination was measured using the KTK (MQ), and object control skill with throw-and-catch task (TC). Sports club (SC) status was obtained by a questionnaire. Boys had higher levels of MPA (F = 50.45, P<0.001) and VPA (F = 11.13, P = 0.001), and were better in TC (F = 39.83, P < 0.001) than girls. SC participants outperformed non-participants in MPA (F = 5.45, P = 0.020) and VPA (F = 11.71, P = 0.001), MQ (F = 31.56, P < 0.001), and TC (F = 15.60, P < 0.001). Moreover, better TC was associated with higher MPA (β = 0.88, t = 2.16, P = 0.031), and higher MQ was associated with higher VPA (β = 0.21, t = 3.87, P < 0.001). The association between PA and MC was found showing that different intensities of PA were associated with different aspects of MC. SC participation may be one important factor promoting PA and MC in children. Therefore, all children, especially girls, should be encouraged to participate in various practices to ensure the development of adequate level of motor competence to be physically active.

Accelerometer activity tracking in horses and the effect of pasture management on time budget

BACKGROUND

Accelerometry is an accepted means of quantifying human physical activity. Quantitative physical activity tracking could be beneficial for studies into equine health and disease prevention, for example in relation to obesity management.

OBJECTIVES

Validate accelerometer use in grazing horses, determine between-day repeatability, and assess the effects of pasture size on time budget (i.e. duration in each activity category).

STUDY DESIGN

Proof of concept.

METHODS

Accelerometers (ActiGraph) were positioned at the poll. Horses underwent 5 min of observed activity in three categories: standing, grazing and ambulating. Receiver-operating characteristic curve analysis, used on ten second data epochs, calculated cut points between the activities. A 20-day study was then undertaken on 6 horses at pasture. Time in each category (per day) was deduced; a Mann Whitney U test was performed to compare standard vs. small paddock and day vs. night turn out.

RESULTS

Cut-off values with the optimum sensitivity (94.7-97.7%) and specificity (94.7-96.8%) were found to be <127.6 counts for standing, 127.6-702.7 counts for grazing and >702.7 counts for ambulating. Repeatability was analysed descriptively: Median (IQR) of the between-day difference in minutes standing, grazing and ambulating were 46.9 (21.3-87.9), 77.3 (40.2-124.5) and 15.6 (6.8-40.2) respectively. Median times standing and ambulating were significantly different between standard and small paddocks: standing: 8.7 vs. 10.3 h (P<0.001); ambulating: 55.7 vs. 39.6 min (P = 0.002). There was no significant difference in the median time spent grazing. There were significant differences between day and night: standing: 32.95% vs. 50.97% (P = 0.001), grazing: 60.81% vs. 46.77% (P<0.001) and ambulating: 4.57% vs. 2.40% (P<0.001).

MAIN LIMITATIONS

Small sample size and lack of cross-validation of cut-off points on independent, 'unseen' data.

CONCLUSIONS

Accelerometry can differentiate standing, grazing and ambulating in horses. Our proof-of-concept study demonstrates modifying pasture size influences activity budgets; opening avenues into studying obesity management.

Relationship Between Sedentary Time and Sleep Duration Among Korean Adolescents

Longer sedentary time and insufficient sleep are common and potentially serious problems among adolescents and have substantially adverse effects on their physical and mental health. In this school-based study, we conducted an ecological momentary assessment using actigraphy to examine the within-subject association between sedentary time and sleep duration among 80 Korean adolescents aged 12–17. Objectively measured sedentary time and sleep duration were recorded over 5 days; participants also completed a self-reported questionnaire and sleep logs. Using a generalized estimating equation, analysis revealed that daily sedentary time was significantly and negatively associated with sleep duration (β = −.36, p = .028). Additionally, the interaction between age and sedentary time significantly affected sleep duration (β = .03, p = .012). These findings suggest the need for school-based interventions that aim to reduce sedentary time and thereby improve sleep duration, helping adolescents, especially younger ones, to achieve a healthier lifestyle.

Improving Cognitive Performance of 9-12 Years Old Children: Just Dance? A Randomized Controlled Trial

Exercise is assumed to have positive effects on children's cognitive performance. However, given the inconclusive evidence for the long-term effects of exercise, it is difficult to advice schools on what specific exercise programs can improve children's cognitive performance. In particular, little is known about the effects of small exercise programs that may be feasible in daily school practice. Therefore, we assessed the effects of a 9-weeks program consisting of daily exercise breaks on children's cognitive performance, aerobic fitness and physical activity levels. We conducted a cluster-randomized controlled trial in 21 classes of eight Dutch primary schools. A total of 512 children aged 9-12 years participated. The exercise intervention had a duration of 9 weeks and consisted of a daily 10-min classroom-based exercise break of moderate to vigorous intensity. Before and after the intervention, we used four cognitive tasks (i.e., the Attention Network Test, Stroop test, d2 test of attention and Fluency task) to measure children's cognitive performance in domains of selective attention, inhibition and memory retrieval. In addition, we measured aerobic fitness with a Shuttle Run test and physical activity during school hours by accelerometers. We analyzed data using mixed models, adjusting for baseline scores, class and school. After 9 weeks, there were no intervention effects on children's cognitive performance or aerobic fitness. Children in the intervention group spent 2.9 min more of their school hours in moderate to vigorous physical activity as compared to the children in the control group. In conclusion, daily 10-min exercise breaks in the classroom did not improve, nor deteriorate cognitive performance in children. The exercise breaks had no effect on children's fitness, and resulted in 2.9 min more time spent in moderate to vigorous physical activity during school hours. Daily exercise breaks can be implemented in the classroom to promote children's physical activity during school time, without adverse effect on their cognitive performance.

Stay in or play out? The influence of weather conditions on physical activity of grade 5 children in Canada

OBJECTIVES

Regular physical activity (PA) in children is essential for their development and prevention of overweight and obesity. Little is known about the effect of day-to-day variations in weather conditions on PA levels in school-aged children, particularly with regard to school compared to non-school days and girls compared to boys.

METHODS

Daily step count (7:00 a.m.-9:00 p.m.) from 972 grade 5 students aged 10-11 years from 60 schools across Alberta, Canada, was collected using time-stamped pedometers (minimum wear time of two school and one non-school days) during March-June 2013. Time-matched weather conditions (actual and feels-like temperature, cloud coverage, and precipitation amount) were obtained from local weather stations in Alberta during the same period. Multilevel mixed-effect regression models were used to estimate the effect of each weather condition on daily step count.

RESULTS

A 1 °C increase in feels-like temperature was associated with 26 more steps/day (p < 0.05), while 1-unit increase in cloud coverage was associated with 61 fewer steps/day (p < 0.01). Compared to no precipitation, heavy precipitation (> 5 mm/day) was associated with 1022 fewer steps/day (p < 0.01). Students' PA levels were associated with weather conditions more on non-school vs. school days and more among girls vs. boys.

CONCLUSION

Results suggest that daily weather conditions can affect PA in school children, particularly outside school hours, and should be considered when evaluating PA levels or designing interventions to promote PA in children. Findings provide support for increased investment toward creating weather-appropriate physical activity opportunities for wet and colder days to prevent PA decline in children during inclement weather conditions.

Accuracy of Accelerometers for Measuring Physical Activity and Levels of Sedentary Behavior in Children: A Systematic Review

Objectives: This systematic review evaluated the accuracy of triaxial and omnidirectional accelerometers for measuring physical activity and sedentary behavior in children. Design: Systematic review of the literature. Methods: We comprehensively searched several databases for studies published from January 1996 through June 2018 that reported diagnostic accuracy measures in children and adolescents (age 3-18 years) and compared accelerometers with energy expenditure using indirect calorimetry. Results: We included 11 studies that enrolled 570 participants. All studies used indirect calorimetry as the reference standard. Across the studies, median sensitivity ranged from 46% to 96% and median specificity ranged from 71% to 96%. Median area under the curve ranged from 69% to 98%. Conclusions: Accuracy measures were greatest when detecting sedentary behavior and lowest when detecting light physical activity. Accuracy was higher when the accelerometer was placed on the hip compared with the wrist. The current evidence suggests that triaxial and omnidirectional accelerometers are accurate in measuring sedentary behavior and physical activity levels in children.

Physical activity levels of children and adolescents with moderate-to-severe intellectual disability

Background

Regular participation of children and adolescents with intellectual disabilites in physical activity is important to maintain good health and to acquire motor skills. The aim of this study was to investigate the habitual physical activity in these children.

Methods

Sixty‐eight children and adolescents (2–18 years) with a moderate‐to‐severe intellectual disability were included in the analyses. They wore an accelerometer on eight consecutive days. Data was analysed by use of descriptive statistics and multiple linear regression analyses.

Results

The participants took on average 6,677 ± 2,600 steps per day, with intensity of 1,040 ± 431 counts per minute. In total, 47% of the participants were meeting physical activity recommendations. Low motor development was associated with low physical activity.

Conclusions

As more than half of the participants were not meeting the recommendations, family and caregivers of these children should focus on supporting and motivating them to explore and expand their physical activities.

Results of a feasibility cluster randomised controlled trial of a peer-led school-based intervention to increase the physical activity of adolescent girls (PLAN-A)

BACKGROUND

Most adolescent girls in the UK do not meet government physical activity recommendations and effective interventions are needed. This study reports the results of a feasibility trial of PLAN-A, a novel school-based peer-led physical activity intervention for adolescent girls.

METHODS

A two-arm cluster randomised controlled feasibility study was conducted in six English secondary schools (4 intervention & 2 control). Year 8 (age 12-13) girls were eligible and randomisation was at school-level. The intervention involved training Year 8 girls (out of school for two consecutive days, plus one top-up day 5 weeks later), who were identified by their peers as influential, to provide informal support to their friends to increase their physical activity. Feasibility of the intervention and the research was examined, including: recruitment, training attendance and data provision rates, evidence of promise of the intervention to affect weekday moderate-to-vigorous physical activity (MVPA), intervention cost and estimation of the sample size for a definitive trial. Accelerometer and questionnaire data were collected at the beginning of Year 8 (Time 0), the end of Year 8 (10-weeks after peer-supporter training) and the beginning of Year 9 (Time 2).

RESULTS

Four hundred twenty-seven girls were recruited (95% recruitment rate). 55 girls consented to be a peer-supporter and 53 peer-supporters were trained (97% of those invited). Accelerometer return rates exceeded 85% at each time point and wear time criteria was met by 83%, 71% and 62% participants at Time 0, 1 and 2 respectively. Questionnaire data were provided by >91% of participants at each time point. Complete-case adjusted linear regression analysis showed evidence of a 6.09 minute (95% CI = 1.43, 10.76) between-arms difference in weekday MVPA at Time 2 in favour of the intervention arm. On average PLAN-A cost £2685 per school to deliver (£37 per Year 8 girl). There were no adverse events. A trial involving 20 schools would be adequately powered to detect a between-arms difference in weekday MVPA of at least six minutes.

CONCLUSIONS

The PLAN-A intervention adopts a novel peer-led approach, is feasible, and shows evidence of promise to positively affect girls' physical activity levels. A definitive trial is warranted.

TRIAL REGISTRATION

ISCTRN, ISRCTN12543546, Registered on 28/7/2015, URL of registry record: http://www.isrctn.com/ISRCTN12543546.

Tracking of Pedometer-Determined Physical Activity: A 16-Year Follow-Up Study

Background: The aims of this study were to explore the effect of time and long-termed tracking on pedometer-determined physical activity (PA) from early adolescent to the 30s. Methods: PA was measured with pedometers [Yamax™ (SW-200)] during 2000 (time 1), 2003 (time 2), 2005 (time 3), 2010 (time 4), and 2016 (time 5). Anthropometric data were collected during time 1. Data from 59 participants (n = 32 males) were analyzed from early adolescent (time 1) to the 30s (time 5). Results: There was an effect of time for males (P = .005, η2 = .76) and females (P = .002, η2 = .50) where steps per day decreased. Males steps per day tracked between time 1 and time 2 (r = .41, P = .021), time 1 and time 3 (r = .38, P = .03), time 3 and time 4 (r = .42, P = .015), and time 4 and time 5 (r = .50, P = .003). Females steps per day tracked between time 4 and time 5 (r = .39, P = .04). Males took more steps per day than females during time 1 (P = .018), whereas females took more steps per day during time 2 (P = .043) and time 3 (P = .03). Conclusion: There was a significant effect of time, where steps per day decreased between the 5 times of measurement. Steps per day tracked low to moderate in the short time span, yet tracked nonsignificantly from early adolescent to the 30s.

Gender-specific effects of physical activity on children's academic performance: The Active Smarter Kids cluster randomized controlled trial

Active learning combines academic content with physical activity (PA) to increase child PA and academic performance, but the impact of active learning is mixed. It may be that this is a moderated relationship in which active learning is beneficial for only some children. This paper examine the impact of baseline academic performance and gender as moderators for the effects of active learning on children's academic performance. In the ASK-study, 1129 fifth-graders from 57 Norwegian elementary schools were randomized by school to intervention or control in a physical activity intervention between November 2014 and June 2015. Academic performance in numeracy, reading, and English was measured and a composite score was calculated. Children were split into low, middle and high academic performing tertiles. 3-way-interactions for group (intervention, control)∗gender (boys, girls)∗academic performance (tertiles) were investigated using mixed model regression. There was a significant, 3-way-interaction (p=0.044). Both boys (ES=0.11) and girls (ES=0.18) in the low performing tertile had a similar beneficial trend. In contrast, middle (ES=0.03) and high performing boys (ES=0.09) responded with small beneficial trends, while middle (ES=-0.11) and high performing girls (ES=-0.06) responded with negative trends. ASK was associated with a significant increase in academic performance for low performing children. It is likely that active learning benefited children most in need of adapted education but it may have a null or negative effect for those girls who are already performing well in the sedentary classroom. Differences in gendered responses are discussed as a possible explanation for these results.

TRIAL REGISTRATION

Clinicaltrials.gov registry, trial registration number: NCT02132494.

The effectiveness of school-based physical activity interventions for adolescent girls: A systematic review and meta-analysis

Physical activity (PA) decreases during the transition from childhood to adolescence, with larger declines observed in girls. School-based interventions are considered the most promising approach for increasing adolescents' PA levels although, it is unclear which types of school-based interventions have the greatest impact. The objective of this systematic review is to assess the impact and design of school-based PA interventions targeting adolescent girls. A systematic search was conducted using four electronic databases (PubMed, Web of Science, SPORTDiscus and PsychInfo). This systematic review was registered with PROSPERO (Registration number: CRD42016037428) and PRISMA guidelines (2009) were followed throughout. Twenty studies were identified as meeting the inclusion criteria and were included in a narrative synthesis. Seventeen studies were eligible for inclusion in a meta-analysis. There was a significant small positive treatment effect for school-based PA interventions for adolescent girls (k=17, g=0.37, p<0.05). After an outlier was removed (residual z=7.61) the average treatment effect was significantly reduced, indicating a very small positive effect (k=16, g=0.07, p=0.05). Subgroup analysis revealed very small significant effects for multi-component interventions (k=7, g=0.09, p<0.05), interventions underpinned by theory (k=12, g=0.07, p<0.05), and studies with a higher risk of bias (k=13, g=0.09, p<0.05). Intervention effects were very small which indicates that changing PA behaviors in adolescent girls through school-based interventions is challenging. Multi-component interventions and interventions underpinned by theory may be the most effective approaches to positively change adolescent girls' PA.

Validity of Accelerometry to Measure Physical Activity Intensity in Children With an Acquired Brain Injury

PURPOSE

To evaluate the validity of the ActiGraph accelerometer (AG) to differentiate between standardized, physical activity tasks using oxygen consumption ((Equation is included in full-text article.)O2) as the criterion measure in children and adolescents with an acquired brain injury; to determine vector magnitude activity intensity cut-points; to compare performance of cut-points to previously published cut-points.

METHODS

Twenty-seven children performed standardized walking and stepping activities wearing a portable indirect calorimeter, AG, and heart rate monitor. Differences in (Equation is included in full-text article.)O2 and AG vector magnitude activity counts were measured during activities. Receiver operating characteristic curves were determined for intensity cut-points.

RESULTS

(Equation is included in full-text article.)O2 and AG activity counts significantly increased as walking speed increased. Discrimination of the newly derived cut-points was excellent and demonstrated greater agreement compared with the previously published cut-points.

CONCLUSION

Output from accelerometers can differentiate physical activity intensity in children with an acquired brain injury. Future studies can apply these cut-points to evaluate physical activity performance.

Physical Activity in Pediatric Pulmonary Arterial Hypertension Measured by Accelerometry. A Candidate Clinical Endpoint

RATIONALE

The development of evidence-based treatment guidelines for pediatric pulmonary arterial hypertension (PAH) is hampered by lack of pediatric clinical trials. Trial design is hampered by lack of a feasible clinical endpoint in this population.

OBJECTIVES

To evaluate the use of accelerometry for measuring physical activity (PA) in pediatric PAH and to investigate its correlation with clinical disease severity markers.

METHODS

We included children from the Dutch National Network for Pediatric Pulmonary Hypertension. Control patients were recruited from the outpatient cardiology clinic of the Beatrix Children's Hospital. Children were asked to wear the accelerometer for 7 days. Vector magnitude counts per minute (VM CPM) and time per day spent in different PA intensity levels were defined as accelerometer outcomes.

MEASUREMENTS AND MAIN RESULTS

VM CPM was lower in children with PAH (n = 29) than in controls (n = 60; 647 vs. 921; P < 0.001). Children with PAH spent less time in moderate and vigorous PA (13 vs. 29 min/d and 2 vs. 13 min/d, respectively; P < 0.001). Time spent in moderate and vigorous PA correlated inversely with World Health Organization functional class. Time spent in moderate PA correlated positively with 6-minute-walk distance. In post hoc analyses, VM CPM and time spent in moderate/vigorous combined and vigorous PA were associated with outcome (P ≤ 0.044).

CONCLUSIONS

PA is markedly decreased in children with PAH. Accelerometer output correlated with clinical disease severity markers and may predict outcome. We showed an exciting potential of PA as a meaningful endpoint for clinical trials in pediatric PAH, although its clinical utility and prognostic value need to be further validated.

Time2bHealthy - An online childhood obesity prevention program for preschool-aged children: A randomised controlled trial protocol

BACKGROUND

The use of parent-focused internet-based programs for the prevention and treatment of childhood obesity has shown promise but there is an acknowledged gap in parent-focused interventions which target the early childhood stage.

METHODS

The aim of this study is to determine the efficacy of Time2bHealthy - an online healthy lifestyle program for parents of preschool-aged children. The program will be evaluated using a two-arm, parallel, randomised controlled design. The 11-week program is underpinned by Social Cognitive Theory and consists of interactive modules on healthy eating, physical activity, screen-time and sleep. The intervention also involves elements of social media, where participants share discuss ideas and experiences and they can interact and obtain information with experts. Time2bHealthy is being compared to a comparison condition. Outcomes include change in BMI (primary outcome), dietary intake, physical activity, sleep, child feeding, parental role-modelling and parent self-efficacy. Process evaluation data, such as adherence and engagement with the online forums, will also be collected.

DISCUSSION

Time2bHealthy is the first randomised controlled trial to our knowledge to assess the efficacy of an online parent-focussed healthy lifestyle program for preschool-aged children in changing body mass index. Early childhood is a crucial time for establishing healthy lifestyle behaviours and parents play an important role. This study therefore fills an important gap in the literature. If found to be efficacious, Time2bHealthy has potential for broad-reach access and translation into primary health care services.

TRIAL REGISTRATION

The study is registered with the Australian and New Zealand Clinical Trials Registry (12616000119493).