School day physical activity patterns of Pima Indian children in two communities

Cluster Analysis to Find Temporal Physical Activity Patterns Among US Adults

Physical activity (PA) is known to be a risk factor for obesity and chronic diseases such as diabetes and metabolic syndrome. Few attempts have been made to pattern the time of physical activity while incorporating intensity and duration in order to determine the relationship of this multi-faceted behavior with health. In this paper, we explore a distance-based approach for clustering daily physical activity time series to estimate temporal physical activity patterns among U.S. adults (ages 20-65) from the National Health and Nutrition Examination Survey 2003-2006 (NHANES). A number of distance measures and distance-based clustering methods were investigated and compared using various metrics. These metrics include the Silhouette and the Dunn Index (internal criteria), and the associations of the clusters with health status indicators (external criteria). Our experiments indicate that using a distance-based cluster analysis approach to estimate temporal physical activity patterns through the day, has the potential to describe the complexity of behavior rather than characterizing physical activity patterns solely by sums or labels of maximum activity levels.

A Systematic Review of Children's Physical Activity Patterns: Concept, Operational Definitions, Instruments, Statistical Analyses, and Health Implications

Despite the widespread use of the expression “physical activity pattern” (PAP), there apparently is no general consensus regarding its definition. This systematic review aimed to examine available research focussing on (1) definitions of PAP, (2) instruments/techniques used to describe PAP, (3) statistical approaches used to analyse PAP, and (4) implications of PAP on children’s health. A systematic review of the available literature was done to identify studies published up to October 2019, and 76 studies were eligible. None of the studies presented a formal definition of PAP; a wide range of instruments were used to investigate children’s PAP, and most of the revised studies did not explicitly present a formal statistical model to define PAP. Twenty-four papers purported to examine associations between PAP and health indicators. The review highlights no consensus on a clear PAP definition whatever the instrument used to capture it, and we did not find any agreement regarding how best to analyse PAP. We suggest that PAP should be used when targeting the investigation of similarities/dissimilarities, as well as stabilities and/or changes in children’s PA at an intra-personal level. In sum, PAP should be used to best describe individual streams of behaviours, and not exclusively PA levels/intensities.

Sleep and Physical Activity Patterns in Urban American Indian Children

Objectives: In this study, we examined patterns of obesity, physical activity (PA), sleep, and screen time in urban American Indian (AI) youth in the 6^th-8^th grade. Methods: A youth sample (N = 36) from 3 middle schools was recruited to participate in this observational sample of convenience. Youth completed a demographic and screen time survey, measurements of height and weight, and wore a wrist accelerometer continuously for 7 days to assess PA and sleep. Results: Approximately 42% of participants were overweight or obese. Average weekday screen time was 254.7±98.1 minutes. Compared to weekdays, weekend sedentary activity increased (weekday, 159.2±81.1 minutes vs weekend, 204.3±91.7 minutes; p = .03) and vigorous PA (weekday, 20.9±19.1 minutes vs weekend, 5.7±8.1 minutes; p = .0001) and moderate-to-vigorous PA (weekday, 192.65±62.3 minutes vs weekend, 141±71.7 minutes; p = .002) decreased. Compared to weekdays, weekend total sleep time (weekday, 512.8±48.6 minutes vs weekend, 555.3±84.3 minutes; p = .007) and time in bed (weekday, 487.3±49.6 minutes vs weekend, 528.6±71.2 minutes; p = .01) increased. Conclusions: Weekday to weekend shifts in PA and sleep must be considered when designing targeted obesity prevention interventions.

Step Counts on Weekdays, Weekends, and During Physical Education of Navajo High School Students

BACKGROUND

Understanding the physical activity patterns of youth is important for the implementation and evaluation of programming and interventions designed to change behavior. To date, little is known about the objectively measured physical activity patterns of Native American youth. Therefore, the purpose of the study was to examine the step counts of Navajo youth during weekdays, weekend days, and physical education classes.

METHODS

Participants included 63 high school students (mean age = 15.14 ± 1.37 years). Youth wore a pedometer (Walk-4-Life 2505) for seven consecutive days. Means and standard deviations were calculated for weekdays, weekend days, and physical education.

RESULTS

Boys averaged 11,078 ± 4400 steps/weekday compared to 6493 ± 5651 on weekend days. Girls averaged 7567 ± 5614 on weekdays compared to 7589 ± 7712 on weekend days. Both boys (20 %) and girls (26 %) accumulated a large percentage of their weekday step counts from physical education classes.

CONCLUSIONS

Findings highlight the importance of additional physical activity opportunities in the community. Youth are falling well short of recommended levels of physical activity with physical education being an important source of physical activity.

An Examination of Four Traditional School Physical Activity Models on Children's Step Counts and MVPA

Schools have been identified as primary societal institutions for promoting children's physical activity (PA); however, limited evidence exists demonstrating which traditional school-based PA models maximize children's PA.

PURPOSE

The purpose of this study was to compare step counts and moderate-to-vigorous physical activity (MVPA) across 4 traditional school PA modules.

METHOD

Step count and MVPA data were collected on 5 consecutive school days from 298 children (Mage = 10.0 ± 0.6 years; 55% female) in Grade 5. PA was measured using the NL-1000 piezoelectric pedometer. The 4 models included (a) recess only, (b) multiple recesses, (c) recess and physical education (PE), and (d) multiple recesses and PE.

RESULTS

Children accumulated the greatest PA on days that they had PE and multiple recess opportunities (5,242 ± 1,690 steps; 15.3 ± 8.8 min of MVPA). Children accumulated the least amount of PA on days with only 1 recess opportunity (3,312 ± 445 steps; 7.1 ± 2.3 min of MVPA). Across all models, children accumulated an additional 1,140 steps and 4.1 min of MVPA on PE days.

CONCLUSIONS

It appears that PE is the most important school PA opportunity for maximizing children's PA. However, on days without PE, a 2nd recess can increase school PA by 20% (Δ = 850 steps; 3.8 min of MVPA).

A systematic review of physical activity levels in Native American populations in Canada and the United States in the last 50 years

Physical activity is beneficial for many chronic conditions. However, activity levels of Native Americans are not well known. This systematic review investigated if Native American populations achieve the recommended physical activity levels, compared current and past activity levels, and assessed the ability of exercise training programmes to improve health outcomes among this population. Electronic databases (e.g. MEDLINE, EMBASE) were searched and citations were cross-referenced. Included articles reported physical activity levels or investigations among Native Americans. This search identified 89 articles: self-report (n = 61), accelerometry and pedometry (n = 10), metabolic monitoring (n = 10) and physical activity interventions (n = 17). Few adults were found to meet the physical activity recommendations (27.2% [95% confidence interval = 26.9-27.5%] self-report, 9% [4-14%] accelerometry). Among children/youth, 26.5% (24.6-28.4%) (self-report) to 45.7% (42.3-49.1%) (pedometry/accelerometry) met the recommendations. Adults and children/youth were generally identified as physically inactive (via doubly labelled water). Overall, Native American adults reported lower activity levels since 2000, compared to 1990s, although similar to 1980s. Few physical activity interventions employed strong methodologies, large sample sizes and objective outcome measures. There is a clear need to increase Native American populations' physical activity. Additional research is required to evaluate exercise training programmes among this population.