Issues and challenges in sedentary behavior measurement

Previous research has shown the negative impact of sedentary behavior on health, including cardiovascular risk factors, chronic disease-related morbidity, and mortality. Accurate measurement of sedentary behavior is thus important to plan effective interventions and to inform public health messages. This article (a) provides an overview of the nature and importance of sedentary behavior, (b) describes measurement methods, including subjective and objective measurement tools, (c) reviews the most important measurement and data processing issues and challenges facing sedentary behavior researchers, and (d) presents key findings from the most recent sedentary behavior measurement-related research. Both subjective and objective measures of sedentary behavior have limitations for obtaining accurate sedentary behavior measurements compliant with the current definitions of sedentary behavior, especially when investigating sedentary behavior as part of the full spectrum of physical behaviors. Regardless of the sedentary behavior measure chosen, researchers must be aware of all possible sources of error inherent to each technique and minimize those errors, thereby increasing validity of the outcome data

Measuring free-living physical activity in COPD patients : Deriving methodology standards for clinical trials through a review of research studies

This article presents a review of the research literature to identify the methodology used and outcome measures derived in the use of accelerometers to measure free-living activity in patients with COPD. Using this and existing empirical validity evidence we further identify standards for use, and recommended clinical outcome measures from continuous accelerometer data to describe pertinent measures of sedentary behaviour and physical activity in this and similar patient populations. We provide measures of the strength of evidence to support our recommendations and identify areas requiring continued research. Our findings support the use of accelerometry in clinical trials to understand and measure treatment-related changes in free-living physical activity and sedentary behaviour in patient populations with limited activity

Measurement considerations of peak stepping cadence measures using national health and nutrition examination survey 2005-2006

Background: This study examined the optimal measurement conditions to obtain reliable peak cadence measures using the accelerometerdetermined step data from the National Health and Nutrition Examination Survey 2005-2006. Methods: A total of 1282 adults (> 17 years) who provided valid accelerometer data for 7 consecutive days were included. The peak 1-and 30-minute cadences were extracted. The sources of variance in peak stepping cadences were estimated using Generalizability theory analysis. A simulation analysis was conducted to examine the effect of the inclusion of weekend days. The optimal number of monitoring days to achieve 80% reliability for peak stepping cadences were estimated. Results: Intraindividual variability was the largest variance component of peak cadences for young and middle-aged adults aged < 60 years (50.55%-59.24%) compared with older adults aged < 60 years (31.62%-41.72%). In general, the minimum of 7 and 5 days of monitoring were required for peak 1-and 30-minute cadences among young and middle-aged adults, respectively, whereas 3 days of monitoring was sufficient for older adults to achieve the desired reliability (0.80). The inclusion of weekend days in the monitoring frame may not be practically important. Conclusions: The findings could be applied in future research as the reference measurement conditions for peak cadences

The effect of an 8-week classroom-based physical activity and sedentary behaviour programme on adolescents' motivation and physical activity

We determine the effect of "ActiveChat" - an 8-week classroom-based physical activity (PA) and sedentary behaviour (SB) programme on adolescents' motivation and PA. Results of the feasibility study provides preliminary evidence suggesting that an 8-week teacher-led classroom-based PA and SB programme has the potential to maintain adolescents' motivation towards PA, and increase in-class levels of PA. This indicates that pedagogical methods could be adapted to incorporate more PA within secondary school classrooms

Classroom-based physical activity and sedentary behavior interventions in adolescents : a systematic review and meta-analysis

Background: It is reported that 81% of adolescents are insufficiently active. Schools play a pivotal role in promoting physical activity (PA) and reducing sedentary behavior (SB). The aim of this systematic review and meta-analysis was to evaluate classroom-based PA and SB interventions in adolescents. Methods: A search strategy was developed using the PICOS framework. Articles were screened using strict inclusion criteria. Study quality was assessed using the Effective Public Health Practice Project quality assessment tool ( http://www.ephpp.ca/tools.html ). Outcome data for preintervention and postintervention were extracted, and effect sizes were calculated using Cohen’s d. Results: The strategy yielded 7574 potentially relevant articles. Nine studies were included for review. Study quality was rated as strong for 1 study, moderate for 5 studies, and weak for 3 studies. Five studies were included for meta-analyses, which suggested that the classroom-based interventions had a nonsignificant effect on PA (P=.55, d=0.05) and a small, nonsignificant effect on SB ( P=.16, d=−0.11). Conclusion: Only 9 relevant studies were found, and the effectiveness of the classroom-based PA and SB interventions varied. Based on limited empirical studies, there is not enough evidence to determine the most effective classroom-based methodology to increase PA and SB

Psychosocial factors related to children’s active school travel : A comparison of two European regions

Peer reviewedPublisher PD

Effectiveness of active school transport interventions : a systematic review and update

Background: Active school transport (AST) is a promising strategy to increase children's physical activity. A systematic review published in 2011 found large heterogeneity in the effectiveness of interventions in increasing AST and highlighted several limitations of previous research. We provide a comprehensive update of that review. Methods: Replicating the search of the previous review, we screened the PubMed, Web of Science, Cochrane, Sport Discus and National Transportation Library databases for articles published between February 1, 2010 and October 15, 2016. To be eligible, studies had to focus on school-aged children and adolescents, include an intervention related to school travel, and report a measure of travel behaviors. We assessed quality of individual studies with the Effective Public Health Practice Project quality assessment tool, and overall quality of evidence with the Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) approach. We calculated Cohen's d as a measure of effect size. Results: Out of 6318 potentially relevant articles, 27 articles reporting 30 interventions met our inclusion criteria. Thirteen interventions resulted in an increase in AST, 8 found no changes, 4 reported inconsistent results, and 5 did not report inferential statistics. Cohen's d ranged from -0.61 to 0.75, with most studies reporting "trivial-to-small" positive effect sizes. Three studies reported greater increases in AST over longer follow-up periods and two Safe Routes to School studies noted that multi-level interventions were more effective. Study quality was rated as weak for 27/30 interventions (due notably to lack of blinding of outcome assessors, unknown psychometric properties of measurement tools, and limited control for confounders), and overall quality of evidence was rated as low. Evaluations of implementation suggested that interventions were limited by insufficient follow-up duration, incomplete implementation of planned interventions, and limited access to resources for low-income communities. Conclusions: Interventions may increase AST among children; however, there was substantial heterogeneity across studies and quality of evidence remains low. Future studies should include longer follow-ups, use standardized outcome measures (to allow for meta-analyses), and examine potential moderators and mediators of travel behavior change to help refine current interventions. Trial registration: Registered in PROSPERO: CRD4201603325

Measuring Activity Energy Expenditure: Accuracy of the GT3X+ and Actiheart Monitors

International Journal of Exercise Science 6(3) : 217-229, 2013. The purpose was to determine the accuracy of the GT3X+ and Actiheart monitors for estimating energy expenditure (EE) and steps. Additionally, to investigate agreement between waist- and wrist-mounted GT3X+ EE outputs. Nineteen participants (mean age=30) completed three treadmill walking trials at self-selected slow, medium, and fast speeds while wearing two GT3X+ (waist and wrist) and an Actiheart. Activity monitor EE was compared to indirect calorimetry criterion EE using Pearson correlations and ANOVAs. A Bland-Altman plot was used to investigate agreement between GT3X+ waist- and wrist-determined EE. GT3X+ determined steps were compared to researcher-counted steps using ANOVAs. EE estimates from all monitors correlated highly with the criterion (r ranged from .72 to .82). However, the GT3X+ (waist and wrist) underestimated EE during slow walking and overestimated EE during fast walking. There were no differences among GT3X+ (waist and wrist) estimates of EE and the criterion during the medium trial. Actiheart estimated EE was not significantly different from measured EE during all trials. The Bland-Altman plot indicated that at EE rates above 4 kcal·min-1, the GT3X+ worn on the wrist underestimated EE compared to when it was worn on the waist. There were no differences between GT3X+ waist-determined steps and researcher-counted steps for all trials. GT3X+ EE correlates highly with measured EE, but has poor absolute agreement during slow and fast walking. GT3X+ step estimates are accurate across the continuum of walking speeds when waist (but not wrist) mounted. Wrist-mounted device outputs are not comparable to waist-mounted outputs. The Actiheart accurately estimates EE

Relationships between wearer assessment and the instrumental measurement of the handle and prickle of knitted wool fabrics

The relationships between wearer-assessed comfort and objectively measured comfort and handle parameters were investigated using 19 pure wool single jersey garments made of single ply yarns. Wearer trials were used to determine prickle discomfort, and whether wearers &ldquo;liked&rdquo; the garments. Fabrics then were objectively evaluated using the Wool HandleMeter, which measures seven primary handle attributes; and the Wool ComfortMeter (WCM), to predict a wearer\u27s perception of fabric-evoked prickle. Wearer responses and the relationships within and between objective measurements and the effect of fibre, yarn and fabrics attributes were analysed by general linear modelling. Mean fibre diameter, fibre diameter coefficient of variation, yarn count, fabric thickness, fabric density, fabric mass per unit area and decatising affected one or more handle parameters. The best model for predicting wearer prickle discomfort accounted for 90.9% of the variance and included only terms for the WCM and WCM2. The WCM was a good predictor whereas mean fibre diameter was a poor predictor of whether wearers &ldquo;liked&rdquo; garments. Wearer assessment of prickle and whether or not wearers &ldquo;liked&rdquo; fabrics were independent of fabric handle assessment. The results indicate that the handle and comfort properties of lightweight, wool jersey fabrics can be quantified accurately using the Wool HandleMeter and the Wool ComfortMeter. For fabric handle, fibre and yarn characteristics were less important than changes in the properties of the fabric

Validity of a two-item physical activity questionnaire for assessing attainment of physical activity guidelines in youth

Background: As physical activity is important for health and well-being, it is essential to monitor population prevalence of physical activity. Surveillance is dependent on the use of valid and reliable measurement tools. The PACE+ questionnaire is used globally in youth and has acceptable reliability; however it has not been validated in a European sample. The purpose of this study is to validate this instrument in a sample of 10-18 year old Irish youth. Methods: Participants (n=419, 45.7 % male) completed the PACE+ two-item questionnaire and were asked to wear an Actigraph accelerometer for eight consecutive days. Freedson cut-points were used to estimate moderate to vigorous physical activity from accelerometer counts. Analyses compared self-report and accelerometry data in participants with (1) ≥5 and (2) seven valid accelerometer days. Calculations were performed for the whole sample, and were stratified by sex and school level (primary; post-primary). Results: Spearman correlations between self-reported physical activity levels and accelerometry derived minutes of moderate-to-vigorous physical activity per day were small (r=0.27; seven valid days) to moderate (r=0.34; ≥5 valid days). Higher correlations were found in older participants (post-primary r=0.39; primary r=0.24) and females (r=0.39; males r=0.27) using ≥5 valid days. The agreement level was high (68-96 %). The accuracy of classifying those not meeting the guidelines (specificity) was moderate to high (59-100 %). Conclusions: The PACE+ self-report instrument has acceptable validity for assessing non-achievement of the adolescent physical activity recommendations. The validity is higher in females and increases with age. The continued use of the tool is recommended and will allow for comparability between studies, tracking of physical activity over time including trends in youth population prevalence