Accelerometry is increasingly used as a physical activity surveillance device that can quantify the amount of time spent moving at a range of intensities. This study proposes physical activity intensity cut-points for the Actical accelerometer. Thirty-eight volunteers completed a multi-stage treadmill protocol at 3, 5, and 8 km · h⁻¹ (2, 3.3, and 8 METs) while wearing Actical accelerometers initialized to collect data in 60-s epochs. Using a decision boundary analytical approach, moderate and vigorous physical activity intensity cut-points were derived for the Actical accelerometer. In adults (n = 26), the cut-point for moderate physical activity intensity occurred at 1535 counts per minute and the vigorous cut-point occurred at 3960 counts per minute. In children (n = 12), the cut-point for moderate physical activity intensity occurred at 1600 counts per minute and the vigorous cut-point occurred at 4760 counts per minute. Improved classification of physical activity intensity using the decision boundary cut-points was observed compared with using mean values for each protocol stage. The cut-points derived are recommended for use in adults. The cut-points derived for children confirm the findings of previous studies.
BACKGROUND: Point-of-decision prompts (PODP) are effective at increasing physical activity and sedentary behavior in the workplace. However, current research that investigates the influence of PODPs on sedentary behavior outside of the workplace is lacking. PURPOSE: To determine if a PODP targeting sedentary behavior influenced the proportion of standing individuals during presentations at an academic conference. METHODS: Twelve, one-hour groups of presentation sessions (Global Summit on the Physical Activity of Children conference, May 2014) were included in this study; half were randomly assigned to the intervention group and half to the control group. The intervention group was exposed to an oral PODP at the beginning and middle of the presentations. Researchers performed three counts: beginning (e.g. first 10 minutes), middle (e.g. 30-40 minutes), and end (e.g. 50-60 minutes); each count included the number of individuals in the audience and the number of standing individuals. RESULTS: A significantly larger proportion of individuals chose to stand during intervention group presentations (16.9± 2.0%) compared to control group presentations (10.5± 1.5%; chi2=7.13; p < 0.05). CONCLUSIONS: This study demonstrated the effectiveness of PODPs at decreasing sedentary behavior during an academic conference. PODPs are simple, cost-effective interventions that require minimal time commitment, and represent a population health intervention that could reduce sedentary behavior in a large group setting.
ParticipACTION est un organisme de communications et de marketing social voué à la promotion de l’activité physique au Canada, qui a été fondé à l’automne 1971, a cessé ses activités en 2001 et a été relancé en 2007. Conçues comme une expérience naturelle en santé publique, les données probantes ont été tirées à la fois d’une enquête fondée sur la population et portant sur les connaissances, la sensibilisation, la compréhension de l’activité physique et les niveaux d’activité physique des Canadiens (à l’échelle de l’individu) et de sondages et d’entrevues auprès d’informateurs clés visant à examiner le pouvoir d’action, l’état de préparation et le soutien des organisations en matière de promotion de l’activité physique (à l’échelle de l’organisation). Cet article vise en premier lieu à donner un aperçu de certaines des principales initiatives entreprises par la « nouvelle version » de ParticipACTION susceptibles d’avoir contribué à des changements sur le plan individuel ou organisationnel. En second lieu, il prépare le terrain pour les trois études empiriques de cette série d’articles consacrée aux résultats de suivi.
Objective To determine if a point-of-decision prompt (PODP) targeting sedentary behaviour influenced the proportion of standing individuals during presentations at an academic conference. Methods Twelve, one-hour groups of presentation sessions (Global Summit on the Physical Activity of Children conference, May 2014) were included in this study; half were randomly assigned to the intervention group and half to the control group. The intervention group was exposed to an oral PODP at the beginning and middle of the presentations. Researchers performed three counts: beginning (e.g. first 10min), middle (e.g. 30–40min), and end (e.g. 50–60min); each count included the number of individuals in the audience and the number of standing individuals. Results A significantly larger proportion of individuals chose to stand during intervention group presentations (16.9±2.0%) compared to control group presentations (10.5±1.5%; chi 2 =7.13; p<0.05). Conclusions This study demonstrated the effectiveness of PODPs at decreasing sedentary behaviour during an academic conference. PODPs are simple, cost-effective interventions that require minimal time commitment, and represent a population health intervention that could reduce sedentary behaviour in a large group setting.
Examination of the timing and patterns of daily activity are crucial in understanding when children accumulate the highest levels of physical activity. The objectives of this study were to examine moderate-to-vigorous physical activity (MVPA) patterns accrued by time of day among Kenyan children, and compare activity patterns in Kenya to those of Canadian children. Physical activity and body weights of participating children were measured by accelerometry and anthropometry, while supplementary self-report data were captured by questionnaires. Data were collected as part of a larger International Study of Childhood Obesity, Lifestyle and Environment (ISCOLE) in Nairobi for ISCOLE-Kenya and in the Ottawa Region for ISCOLE-Canada. A total of 555 Kenyan and 541 Canadian children 9 to 11 years were included in the analyses. In Kenya, boys, under/healthy weight, and children attending public (lower socioeconomic status (SES)) schools were found to have significantly higher MVPA levels compared to girls, overweight/obese, and children attending private (higher SES) schools respectively. MVPA on weekdays was higher than on weekend-days. Activity profiles among Kenyan and Canadian children were very similar; however, Kenyan children had significantly higher MVPA and lower sedentary time on weekend-days. MVPA patterns among urban Kenyan children were largely similar to those of urban Canadian children when assessed by sex, BMI category, and weekday/weekend days. However, in the Kenyan sample, unlike in many higher income countries, lower SES was associated with higher MVPA.
The interrelationships between sleep and daytime movement behaviours have been examined at interindividual level. Studies of within-person, temporal relationships of daytime physical activity (PA) and sedentary behaviour with the previous and subsequent nights' sleep are increasing. The present systematic review and meta-analysis synthesised the results of studies in school-aged children and youth. Eight databases (MEDLINE, PsycINFO, EMBASE, Global Health, PubMed, Web of Science, SPORTDiscus, and CINAHL) were searched for peer-reviewed articles that examined the association between daytime movement behaviours (including PA, sedentary time, or sedentary recreational screen time) and night-time sleep on the same day, or the association between night-time sleep and daytime movement behaviours the next day, in children and youth. A total of 11 studies comprising 9,622 children and youth aged 5-15 years met the inclusion criteria. Sedentary time was negatively associated with the subsequent night's sleep duration (r = -0.12, 95% confidence interval -0.23 to -0.00; I2 = 93%; p = .04). Positive relationships between PA and the previous or subsequent night's sleep duration were observed only for studies that adjusted for accelerometer wear time. There was some evidence suggesting that a longer sleep duration was associated with less sedentary time and a higher proportion of the daytime spent being physically active and vice versa, although the association was weak and based on a limited number of studies. From a clinical perspective, promotion of either sleep hygiene or daytime PA should be planned with considerations of the virtuous or vicious circle between these behaviours and monitor concurrent effects on the others.
Because blood pressure (BP) tracks from childhood to adulthood, assessing levels in youth is relevant. There are no recent BP data for Canadian children and adolescents, and past studies have used a variety of design and measurement devices.With a clinically validated oscillometric device, resting BP was measured in 2,079 respondents aged 6 to 19 years from the Canadian Health Measures Survey. The average of the last five of six BP measures taken one minute apart at a single visit was used in this report. Borderline or elevated BP was defined as greater than or equal to the 90th percentile of US reference values for participants aged 6 to 17 years. Borderline or elevated BP for 18- to 19-year-olds was defined as equal to or greater than 120 systolic BP or equal to or greater than 80 diastolic BP. Participants of any age who reported taking antihypertensive medication in the past month were also defined as having elevated BP.At ages 6 to 11 years, mean (standard error) systolic/diastolic blood pressure was 93(0)/61(1) in boys and 93(0)/60(0) mmHg in girls, and at ages 12 to 19 years, 101(1)/63(1) and 98(1)/63(1) mmHg, respectively. An estimated 2.1% (95% confidence interval 1.3% to 3.0%) of Canadian children and youth had borderline levels; 0.8% (0.4% to 1.4%) had elevated BP.Despite the prevalence of obesity among young people, BP levels were lower than reported in provincial samples, which may, in part, reflect differences in methodologies and measurement instruments.
