The Effect of Sedentary Behaviour on Cardiorespiratory Fitness: A Systematic Review and Meta-Analysis

BACKGROUND

Cardiorespiratory fitness (CRF) is an important indicator of current and future health. While the impact of habitual physical activity on CRF is well established, the role of sedentary behaviour (SB) remains less understood.

OBJECTIVE

We aimed to determine the effect of SB on CRF.

METHODS

Searches were conducted in MEDLINE, Embase, PsycINFO, CINAHL and SPORTDiscus from inception to August 2022. Randomised controlled trials, quasi-experimental studies and cohort studies that assessed the relationship between SB and CRF were eligible. Narrative syntheses and meta-analyses summarised the evidence, and Grading of Recommendations, Assessment, Development and Evaluation (GRADE) certainty was based on evidence from randomised controlled trials.

RESULTS

This review included 18 studies that focused on youth (four randomised controlled trials, three quasi-experimental studies, 11 cohort studies) and 24 on adult populations (15 randomised controlled trials, five quasi-experimental studies, four cohort studies). In youth and adults, evidence from randomised controlled trials suggests mixed effects of SB on CRF, but with the potential for interventions to improve CRF. Quasi-experimental and cohort studies also support similar conclusions. Certainty of evidence was very low for both age groups. A meta-analysis of adult randomised controlled trials found that interventions targeting reducing SB, or increasing physical activity and reducing SB, had a significant effect on post-peak oxygen consumption (mean difference = 3.16 mL.kg-1.min-1, 95% confidence interval: 1.76, 4.57).

CONCLUSIONS

Evidence from randomised controlled trials indicates mixed associations between SB and CRF, with the potential for SB to influence CRF, as supported by meta-analytical findings. Further well-designed trials are warranted to confirm the relationship between SB and CRF, explore the effects of SB independent from higher intensity activity, and investigate the existence of such relationships in paediatric populations.

CLINICAL TRIAL REGISTRATION

PROSPERO CRD42022356218.

The ongoing impact of the COVID-19 pandemic on physical activity and screen time among Canadian youth

Background

The COVID-19 pandemic has caused changes in health behaviours, including participation in physical activity and screen time. The purpose of this paper is to examine trends in physical activity and screen time among Canadian youth from January 2018 to February 2022.

Methods

The Canadian Community Health Survey asks Canadian youth (aged 12 to 17 years) to report the time they spend active by domain: recreation, transportation, school and household. Survey respondents are also asked to report their screen time on school days and non-school days. The present analysis compares the physical activity from four cross-sectional samples collected during 2018 (January to December; n=3,952), January to March 2020 (n=911), September to December 2020 (n=1,573), and January 2021 to February 2022 (n=3,501). Screen time is compared between 2018 and 2021/2022. Sub-annual descriptive analyses examine how physical activity and screen time varied within and between these years.

Results

Before the COVID-19 pandemic, half of Canadian youth met the physical activity recommendation (2018: 49.6%; January to March 2020: 53.7%). The percentage meeting the recommendation dropped in the first year of the pandemic (September to December 2020: 37.3%) and recovered slightly in 2021 (43.8%). From 2018 to 2021, total physical activity dropped by 8.3 minutes per day (58.1 minutes per week) among girls and by 2.1 minutes per day (14.7 minutes per week) among boys. The percentage of youth meeting the screen time recommendation on school days dropped from 40.7% in 2018 to 29.1% in 2021 and from 21.4% in 2018 to 13.2% in 2021 on non-school days.

Interpretation

The COVID-19 pandemic had a detrimental impact on the physical activity and screen time of youth, in particular among girls. This analysis provides an update on how the pandemic has continued to affect the physical activity and screen habits of youth in 2020, 2021, and early 2022.

The ongoing impact of the COVID-19 pandemic on physical activity and screen time among Canadian adults

Background

Canadian and international research has shown that the COVID-19 pandemic led to changes in health behaviours, including participation in physical activity and screen time.

Methods

The Canadian Community Health Survey asks Canadian adults (aged 18 to 64 years) and older adults (aged 65 and older) to report the time they spend active by domain: recreation, transportation, and household and/or occupation. Survey respondents are also asked to report their screen time on days they worked and days they did not work. The present analysis compares the physical activity from four cross-sectional samples collected during 2018 (n=50,093), January to mid-March 2020 (n=13,933), September to December 2020 (n=25,661) and January 2021 to February 2022 (n=45,742). Screen time is compared between 2018 and 2021. Sub-annual analyses examine how physical activity and screen time varied within and between years.

Results

The percentage of 18- to 64-year-old women meeting the physical activity recommendation did not change from 2018 (54.3%) to 2021 (55.1%), while a slight decrease was observed among men (63.0% in 2018 to 59.8% in 2021). The percentage of adults aged 65 years and older meeting the recommendation increased from 2018 to 2021 among both men (40.7% to 43.8%) and women (33.4% to 36.9%). Total physical activity decreased by 17.5 minutes per week among 18- to 64-year-old men and increased by 8.4 minutes per week among 18- to 64-year-old women. Men and women aged 65 and older increased their total physical activity by about 30 minutes per week from 2018 to 2021. The percentage of 18- to 64-year-old adults in the lowest screen time category decreased from 53.9% in 2018 to 45.0% in 2021 on work days and from 37.8% in 2018 to 28.0% in 2021 on non-work days. The percentage of adults aged 65 and older in the lowest screen time category decreased from 49.4% in 2018 to 37.8% in 2021 on work days and from 29.4% in 2018 to 21.5% in 2021 on non-work days.

Interpretation

Physical activity among men aged 18 to 64 years decreased from 2018 to 2021, while women of this age group maintained their physical activity. Older adults increased their physical activity from 2018 to 2021. Many Canadian adults shifted from the lowest screen time category (two hours or less per day) to the highest screen time category (four hours or more per day) during the 2020 and 2021 pandemic years. It is unknown whether the short-term impact of the COVID-19 pandemic on physical activity and screen time will persist over time. Ongoing surveillance of the longer-term impacts of the pandemic on the health behaviours of Canadians is important.

Associations Between Type and Timing of Physical Activity and Sedentary Behavior With Mental Health in Adolescents and Young Adults

BACKGROUND

This cross-sectional study analyzed the association of leisure-time physical activity (PA) and sedentary behavior (SB), nonleisure PA and SB, and total PA and SB in different time segments of the day with mental health among Dutch adolescents and young adults.

METHODS

A total of 881 participants aged 16-25 years completed an online survey. Mental health was assessed using the Mental Health Inventory-5, and participants also reported sex, age, and income. They filled out a questionnaire of types of PA and SB for each hour of the day. Activities were categorized into nonleisure and leisure, during the morning, afternoon, evening, and for the whole day.

RESULTS

Participants (52.8% female, on average 20.8 y) generally engaged in more leisure-time PA and SB during weekends compared with weekdays, and more nonleisure activities on weekdays. Associations varied between time segments and days of the week. Positive associations of leisure-time and total PA during the whole day and evenings with mental health were observed on weekdays. Total, leisure-time, and nonleisure-time SB were associated with worse mental health. Nonleisure PA was not associated with mental health.

CONCLUSIONS

Leisure-time PA was found to have a favorable association with mental health, particularly in the evenings of weekdays and afternoons of weekend days. On the other hand, leisure SB was associated with poorer mental health in most of the time segments analyzed, and nonleisure SB in the evenings was also related to worse mental health. The type and timing of PA and SB behaviors play an important role in the relationship with mental health.

Scientific sinkhole: estimating the cost of peer review based on survey data with snowball sampling

BACKGROUND

There are a variety of costs associated with publication of scientific findings. The purpose of this work was to estimate the cost of peer review in scientific publishing per reviewer, per year and for the entire scientific community.

METHODS

Internet-based self-report, cross-sectional survey, live between June 28, 2021 and August 2, 2021 was used. Participants were recruited via snowball sampling. No restrictions were placed on geographic location or field of study. Respondents who were asked to act as a peer-reviewer for at least one manuscript submitted to a scientific journal in 2020 were eligible. The primary outcome measure was the cost of peer review per person, per year (calculated as wage-cost x number of initial reviews and number of re-reviews per year). The secondary outcome was the cost of peer review globally (calculated as the number of peer-reviewed papers in Scopus x median wage-cost of initial review and re-review).

RESULTS

A total of 354 participants completed at least one question of the survey, and information necessary to calculate the cost of peer-review was available for 308 participants from 33 countries (44% from Canada). The cost of peer review was estimated at $US1,272 per person, per year ($US1,015 for initial review and $US256 for re-review), or US$1.1-1.7 billion for the scientific community per year. The global cost of peer-review was estimated at US$6 billion in 2020 when relying on the Dimensions database and taking into account reviewed-but-rejected manuscripts.

CONCLUSIONS

Peer review represents an important financial piece of scientific publishing. Our results may not represent all countries or fields of study, but are consistent with previous estimates and provide additional context from peer reviewers themselves. Researchers and scientists have long provided peer review as a contribution to the scientific community. Recognizing the importance of peer-review, institutions should acknowledge these costs in job descriptions, performance measurement, promotion packages, and funding applications. Journals should develop methods to compensate reviewers for their time and improve transparency while maintaining the integrity of the peer-review process.

Association of daily and time-segmented physical activity and sedentary behaviour with mental health of school children and adolescents from rural Northeastern Ontario, Canada

Physical activity (PA) and sedentary behaviour (SED) have been linked to the mental health of children and adolescents, yet the timing of behaviours may play a role in this relationship and clarifying this could inform interventions. We explored cross-sectional associations of PA and SED in varying time segments throughout the school day with the mental health of school-aged children and adolescents from rural Northeastern Ontario, Canada. A total of 161 students (56% female, M = 10.3 years old) wore accelerometers for 8 days (7 nights) and completed a self-report survey (parent reported for children younger than 11). Mental health was measured using the Strengths and Difficulties Questionnaire. Accelerometer-measured SED, light PA (LPA), and moderate and vigorous PA (MVPA) were estimated in the time-segments before school (06:00–08:44), school time (08:45–15:04), after school (15:05–16:59), and evenings (17:00–21:59). Associations were tested with multilevel linear regressions while adjusting for confounding factors. Students spent 72.6 min in MVPA, 209.0 min in LPA, and 621.0 min in SED per day. Daily SED was associated with less conduct problems (β = −0.27, p < 0.05). Evening LPA was inversely associated with hyperactivity (β = −1.45, p < 0.05), while SED was associated with hyperactivity and with peer problems before school (β = 1.70 and β = 1.01, respectively, p < 0.05), and during school (β = −0.83 and β = −0.57, respectively, p < 0.05). No associations were observed for MVPA, emotional symptoms, or prosocial behaviour. In conclusion, displacing SED with LPA in some specific periods of the day may benefit the mental health of students; taking this into account could strengthen interventions.

How sedentary are Canadian adults? It depends on the measure

INTRODUCTION

The new Canadian 24-Hour Movement Guidelines for Adults aged 18-64 years and Adults aged 65 years and older recommend that adults limit daily sedentary time to eight hours or less, including three hours or less of recreational screen time. The eight-hour recommendation was centred between the evidence from research using self-reported sitting time (threshold: seven hours or less per day) and accelerometer-measured sedentary time (threshold: nine hours or less per day). The purpose of this study is to compare the percentages of Canadians meeting three different sedentary thresholds (three hours or less per day of screen time, seven hours or less per day of self-reported sitting time and nine hours or less per day of accelerometer-measured sedentary time).

METHODS

This analysis is based on 2,511 adults (aged 18 to 79 years) from Cycle 3 of the Canadian Health Measures Survey, in 2012 and 2013. Screen time and sitting time were assessed via self-report, and average daily sedentary time was assessed using a hip-worn Actical accelerometer.

RESULTS

Adults self-reported an average daily screen time of 3.2 hours (95% confidence interval [CI]: 3.0 to 3.5) and an average daily sitting time of 5.7 hours (95% CI: 5.4 to 6.0). According to accelerometry data, adults accumulated an average of 9.8 hours per day (95% CI: 9.7 to 9.9) of sedentary time. Adherence varied, with 57.7% meeting the self-reported recreational screen time threshold of three hours or less per day, 71.7% meeting the self-reported sitting time threshold of seven hours or less per day and 26.5% meeting the accelerometer-measured sedentary time threshold of nine hours or less per day.

INTERPRETATION

The percentage of Canadian adults meeting the three different sedentary behaviour thresholds varied widely. The findings in this article highlight the difference in sedentary time between what Canadians report versus what is measured by an accelerometer.

School-related sedentary behaviours and indicators of health and well-being among children and youth: a systematic review

BACKGROUND

The purpose of this systematic review was to examine the associations between school-related sedentary behaviours and indicators of health and well-being in children and youth (~ 5-18 years) attending school.

METHODS

This review was conducted to inform the development of School-Related Sedentary Behaviour Recommendations. Peer-reviewed, published, or in-press articles in English were included. Reviews, meta-analyses, and case studies were excluded; all other study designs were eligible. Further, articles had to meet the a priori study criteria for population, intervention, comparator (PROSPERO ID: CRD42021227600). Embase, MEDLINE® ALL, and PsycINFO were searched. Risk of bias was assessed for individual experimental studies using the Cochrane risk of bias assessment tool, and in observational studies based on the GRADE framework and in line with previous systematic reviews examining sedentary behaviours in children. Overall quality of evidence was assessed using the GRADE framework for each outcome category and study design. Results were synthesized narratively, grouped by study design and outcome category. Further, several high-level summaries were conducted to help interpret results.

RESULTS

Evidence was synthesized from 116 reports, including 1,385,038 participants and 1173 extracted associations. More school-related sedentary behaviour was favourably associated with nearly one-third of extracted associations for cognitive (33%) and social-emotional (32%) indicators (e.g., less anxiety), but unfavourably associated with other movement behaviours (e.g., less physical activity) (35%). Active lessons were favourable (72%), compared to more school-related sedentary behaviours, when examining associations for all health and well-being indicators. More homework was favourable across all health and well-being indicators in 4% of extracted associations for primary school children, and 25% of extracted associations for secondary school children. However, ≥2 h/day of homework appeared to be unfavourable for health and well-being. Limitations for synthesized studies included generally low quality of evidence and a lack of studies in South American, African, or low-middle income countries.

CONCLUSIONS

Findings can help inform policy makers, schools, and teachers, regarding the amount of homework assigned and the introduction of active lessons into the classroom to enhance health and well-being of children. More research is needed examining school-related sedentary behaviours and indicators of health and well-being in low- and middle-income countries.

International school-related sedentary behaviour recommendations for children and youth

BACKGROUND

Existing sedentary behaviour guidelines for children and youth target overall sedentary behaviour and recreational screen time, without any specific recommendations regarding school-related sedentary behaviours (i.e., sedentary behaviours performed during the school day, or within the influence of school). The purpose of this paper is to describe the development of international evidence-based recommendations for school-related sedentary behaviours for children and youth, led by the Sedentary Behaviour Research Network (SBRN).

METHODS

A panel of international experts was convened by SBRN in November 2020 to guide the development of these recommendations for children and youth aged ~ 5-18 years. The recommendations were informed by 1) age-relevant existing sedentary behaviour guidelines, 2) published research on the relationship between overall sedentary behaviour and health, 3) a de novo systematic review on the relationship between school-related sedentary behaviours and health and/or academic outcomes, and 4) a de novo environmental scan of the grey literature to identify existing recommendations for school-related sedentary behaviours. Draft recommendations were presented to the Expert Panel in June 2021. Following thorough discussion and modifications, updated recommendations were distributed for stakeholder feedback from July 9-26. Feedback was received from 148 stakeholders across 23 countries, leading to additional updates to the recommendations. Following further rounds of discussion and updates with the Expert Panel in August and September 2021, consensus was achieved on the final recommendations.

RESULTS

A healthy day includes breaking up extended periods of sedentary behaviour and incorporating different types of movement into homework whenever possible, while limiting sedentary homework. School-related screen time should be meaningful, mentally or physically active, and serve a specific pedagogical purpose that enhances learning. Replacing sedentary learning activities with movement-based learning activities, and replacing screen-based learning activities with non-screen-based learning activities, can further support students' health and wellbeing.

DISCUSSION

This paper presents the first evidence-based recommendations for school-related sedentary behaviours for children and youth. These recommendations will support the work of parents, caregivers, educators, school system administrators, policy makers, researchers and healthcare providers interested in promoting student health and academic success.

Timing of sedentary behaviour and access to sedentary activities in the bedroom and their association with sleep quality and duration in children and youth: a systematic review

BACKGROUND

The purpose of this study was to systematically review the relationship between the timing of sedentary behaviours and access to sedentary activities in the bedroom with sleep duration and quality in children and youth. A secondary purpose was to examine whether these relationships differ when comparing screen-based and non-screen-based sedentary activities.

METHODS

We searched four databases for peer-reviewed studies published between 1 January 2010 and 19 January 2021. Risk of bias assessment for each study and certainty of evidence were assessed using the GRADE framework.

RESULTS

We identified 44 eligible papers reporting data from 42 separate datasets and including 239 267 participants. Evening participation in screen-based sedentary behaviours and access to screen-based devices in the bedroom were associated with reduced sleep duration and quality. Daytime screen use was also associated with reduced sleep duration, although this was examined in relatively few studies. Whether performed during the day or night, non-screen-based sedentary behaviours were not consistently associated with sleep duration or quality. The quality of evidence was rated as low to very low for all outcomes.

CONCLUSION

In order to maximize sleep duration and quality, children and youth should be encouraged to minimize screen time in the evening and remove screens from bedrooms. (PROSPERO registration no.: CRD42020189082).

Timing of physical activity within the 24-hour day and its influence on health: a systematic review

BACKGROUND

Recent studies report that the health benefits of physical activity differ depending on whether the activity is performed in the morning, afternoon or evening. The purpose of this systematic review was to examine whether the timing of physical activity within the 24-hour day is associated with health.

METHODS

Five databases were searched for English or French language peer-reviewed studies that examined whether the timing of physical activity within the day is associated with health. No limits were placed on publication year, study population, study design or health outcomes. Studies that examined acute effects of physical activity or timing of physical activity around food intake were excluded.

RESULTS

This systematic review examined 35 studies, with 17 259 participants, and the following health outcomes: measures of sleep health, adiposity, fat-free mass and muscle size, cardiometabolic biomarkers, physical function and mobility, mental health, and risk of cardiovascular disease, cancer, and mortality. Heterogeneity across studies precluded meta-analyses, and we present our findings using narrative syntheses. Of the 35 studies, 11 reported that morning physical activity provides greater health benefits than afternoon/ evening physical activity, while 12 found that morning physical activity provides fewer health benefits than afternoon/evening physical. In the remaining 12 studies, there was no clear difference in health benefits based on the timing of physical activity. The quality of evidence for the different health outcomes across study designs was very low.

CONCLUSION

There is no consistent evidence that physical activity at one time of day provides more favourable health benefits than physical activity at a different time of day. (PROSPERO registration no.: CRD42021231088).

Sleep timing and health indicators in children and adolescents: a systematic review

INTRODUCTION

To continue to inform sleep health guidelines and the development of evidence-based healthy sleep interventions for children and adolescents, it is important to better understand the associations between sleep timing (bedtime, wake-up time, midpoint of sleep) and various health indicators. The objective of this systematic review was to examine the associations between sleep timing and 9 health indicators in apparently healthy children and adolescents 5 to 18 years old.

METHODS

Studies published in the 10 years preceding January 2021 were identified from searches in four electronic databases. This systematic review followed the guidelines prescribed in PRISMA 2020, the methodological quality and risk of bias were scored, and the summary of results used a best-evidence approach for accurate and reliable reporting.

RESULTS

Forty-six observational studies from 21 countries with 208 992 unique participants were included. Sleep timing was assessed objectively using actigraphy in 24 studies and subjectively in 22 studies. The lack of studies in some of the health outcomes and heterogeneity in others necessitated using a narrative synthesis rather than a metaanalysis. Findings suggest that later sleep timing is associated with poorer emotional regulation, lower cognitive function/academic achievement, shorter sleep duration/ poorer sleep quality, poorer eating behaviours, lower physical activity levels and more sedentary behaviours, but few studies demonstrated associations between sleep timing and adiposity, quality of life/well-being, accidents/injuries, and biomarkers of cardiometabolic risk. The quality of evidence was rated as "very low" across health outcomes using GRADE.

CONCLUSION

The available evidence, which relies on cross-sectional findings, suggests that earlier sleep timing is beneficial for the health of school-aged children and adolescents. Longitudinal studies and randomized controlled trials are needed to better advance this field of research. (PROSPERO registration no.: CRD42020173585).

Sedentary behaviour and health in adults: an overview of systematic reviews

The purpose of this overview of systematic reviews was to determine the relationship between different types and patterns of sedentary behaviour and selected health outcomes in adults and older adults. Five electronic databases were last searched in May, 2019, with a 10-year search limit. Included reviews met the a priori population (community-dwelling adults aged 18 years and older), intervention/exposure/comparator (various types and/or patterns of sedentary behaviour), and outcomes criteria. Eighteen systematic reviews were included in the evidence synthesis. High levels of sedentary behaviour are unfavourably associated with cognitive function, depression, function and disability, physical activity levels, and physical health-related quality of life in adults. Reducing or breaking up sedentary behaviour may benefit body composition and markers of cardiometabolic risk. Total sedentary behaviour and TV viewing were most consistently associated with unfavourable health outcomes, while computer and Internet use may be favourably associated with cognitive function for older adults. The quality of evidence within individual reviews (as assessed by review authors) varied from low to high, while the certainty of evidence was low to very low. These findings have important public health implications, suggesting that adults should avoid high levels of sedentary behaviour and break-up periods of prolonged sitting. (PROSPERO registration nos.: CRD42019123121 and CRD42019127157.) Novelty High levels of sedentary behaviour are unfavourably associated with important health outcomes in adults. Reducing or breaking up sedentary behaviour may benefit body composition and markers of cardiometabolic risk. Computer and Internet use may be favourably associated with cognitive function in older adults.

A systematic review of compositional data analysis studies examining associations between sleep, sedentary behaviour, and physical activity with health outcomes in adults

This systematic review determined if the composition of time spent in movement behaviours (i.e., sleep, sedentary behaviour (SED), light physical activity, and moderate-to-vigorous physical activity (MVPA)) is associated with health in adults. Five electronic databases were searched in August 2019. Studies were eligible for inclusion if they were peer-reviewed, examined community-dwelling adults, and used compositional data analysis to examine the associations between the composition of time spent in movement behaviours and health outcomes. Eight studies (7 cross-sectional, 1 prospective cohort) of >12 000 unique participants were included. Findings indicated that the 24-h movement behaviour composition was associated with all-cause mortality (1 of 1 analyses), adiposity (4 of 4 analyses), and cardiometabolic biomarkers (8 of 15 analyses). Reallocating time into MVPA from other movement behaviours was associated with favourable changes to most health outcomes and taking time out of SED and reallocating it into other movement behaviours was associated with favourable changes to all-cause mortality. The quality of evidence was very low for all health outcomes. In conclusion, these findings support the notion that the composition of movement across the entire 24-h day matters, and that recommendations for sleep, SED, and physical activity should be combined into a single public health guideline. (PROSPERO registration no.: CRD42019121641.) Novelty The 24-h movement behaviour composition is associated with a variety of health outcomes. Reallocating time into MVPA is favourably associated with health. Reallocating time out of SED is associated with favourable changes to mortality risk.

Canadian 24-Hour Movement Guidelines for Adults aged 18–64 years and Adults aged 65 years or older: an integration of physical activity, sedentary behaviour, and sleep

The Canadian Society for Exercise Physiology assembled a Consensus Panel representing national organizations, content experts, methodologists, stakeholders, and end-users and followed an established guideline development procedure to create the Canadian 24-Hour Movement Guidelines for Adults aged 18–64 years and Adults aged 65 years or older: An Integration of Physical Activity, Sedentary Behaviour, and Sleep. These guidelines underscore the importance of movement behaviours across the whole 24-h day. The development process followed the strategy outlined in the Appraisal of Guidelines for Research and Evaluation (AGREE) II instrument. A large body of evidence was used to inform the guidelines including 2 de novo systematic reviews and 4 overviews of reviews examining the relationships among movement behaviours (physical activity, sedentary behaviour, sleep, and all behaviours together) and several health outcomes. Draft guideline recommendations were discussed at a 4-day in-person Consensus Panel meeting. Feedback from stakeholders was obtained by survey (n = 877) and the draft guidelines were revised accordingly. The final guidelines provide evidence-based recommendations for a healthy day (24-h), comprising a combination of sleep, sedentary behaviours, and light-intensity and moderate-to-vigorous-intensity physical activity. Dissemination and implementation efforts with corresponding evaluation plans are in place to help ensure that guideline awareness and use are optimized.

Novelty First ever 24-Hour Movement Guidelines for Adults aged 18–64 years and Adults aged 65 years or older with consideration of a balanced approach to physical activity, sedentary behaviour, and sleep Finalizes the suite of 24-Hour Movement Guidelines for Canadians across the lifespan

Sleep timing, sleep consistency, and health in adults: a systematic review

The objective of this systematic review was to examine the associations between sleep timing (e.g., bedtime/wake-up time, midpoint of sleep), sleep consistency/regularity (e.g., intra-individual variability in sleep duration, social jetlag, catch-up sleep), and health outcomes in adults aged 18 years and older. Four electronic databases were searched in December 2018 for articles published in the previous 10 years. Fourteen health outcomes were examined. A total of 41 articles, including 92 340 unique participants from 14 countries, met inclusion criteria. Sleep was assessed objectively in 37% of studies and subjectively in 63% of studies. Findings suggest that later sleep timing and greater sleep variability were generally associated with adverse health outcomes. However, because most studies reported linear associations, it was not possible to identify thresholds for “late sleep timing” or “large sleep variability”. In addition, social jetlag was associated with adverse health outcomes, while weekend catch-up sleep was associated with better health outcomes. The quality of evidence ranged from “very low” to “moderate” across study designs and health outcomes using GRADE. In conclusion, the available evidence supports that earlier sleep timing and regularity in sleep patterns with consistent bedtimes and wake-up times are favourably associated with health. (PROSPERO registration no.: CRD42019119534.)

Novelty This is the first systematic review to examine the influence of sleep timing and sleep consistency on health outcomes. Later sleep timing and greater variability in sleep are both associated with adverse health outcomes in adults. Regularity in sleep patterns with consistent bedtimes and wake-up times should be encouraged.

Resistance training and health in adults: an overview of systematic reviews

The objective of this overview of systematic reviews was to determine the benefits and harms of resistance training (RT) on health outcomes in adults aged 18 years or older, compared with not participating in RT. Four electronic databases were searched in February 2019 for systematic reviews published in the past 10 years. Eligibility criteria were determined a priori for population (community dwelling adults), intervention (exclusively RT), comparator (no RT or different doses of RT), and health outcomes (critical: mortality, physical functioning, health-related quality of life, and adverse events; important: cardiovascular disease, type 2 diabetes mellitus, mental health, brain health, cognitive function, cancer, fall-related injuries or falls, and bone health). We selected 1 review per outcome and we used the GRADE process to assess the strength of evidence. We screened 2089 records and 375 full-text articles independently, in duplicate. Eleven systematic reviews were included, representing 364 primary studies and 382 627 unique participants. RT was associated with a reduction in all-cause mortality and cardiovascular disease incidence, and an improvement in physical functioning. Effects on health-related quality of life or cognitive function were less certain. Adverse events were not consistently monitored or reported in RT studies, but serious adverse events were not common. Systematic reviews for the remaining important health outcomes could not be identified. Overall, RT training improved health outcomes in adults and the benefits outweighed the harms. (PROSPERO registration no.: CRD42019121641.)

Novelty This overview was required to inform whether there was new evidence to support changes to the recommended guidelines for resistance training.

Balance and functional training and health in adults: an overview of systematic reviews

This overview of systematic reviews examined the effect of balance and functional strength training on health outcomes in adults aged 18 years or older, to inform the Canadian 24-hour Movement Guidelines. Four electronic databases were searched for systematic reviews published between January 2009 and May 2019. Eligibility criteria were determined a priori for population (community-dwelling adults), intervention (balance and functional training), comparator (no intervention or different types/doses), and outcomes (critical: falls and fall-related injuries; adverse events; important: physical functioning and disability; health-related quality of life; physical activity; and sedentary behaviour). Two reviewers independently screened studies for eligibility and performed AMSTAR 2 assessment. One review was selected per outcome. Of 3288 records and 355 full-text articles, 5 systematic reviews were included, encompassing data from 15 890 participants in 23 countries. In adults 65 years and older, balance and functional training and Tai Chi reduced the rate of falls and the number of people who fell, and improved aspects of physical functioning and physical activity. The effect on health-related quality of life and falls requiring hospitalization was uncertain. While inconsistently monitored, only 1 serious adverse event was reported. No evidence was available in adults under age 65 years. Included systematic reviews and primary evidence reported by review authors ranged in quality. Overall, participation in balance and functional training reduced falls and improved health outcomes in adults 65 years of age and older. PROSPERO registration no.: CRD42019134865.

Novelty This overview informs updated guidelines for balance training in adults. Balance and functional training reduced falls and improved health outcomes.

Development and application of an outcome-centric approach for conducting overviews of reviews

There are gaps in current guidance concerning how to conduct overviews of systematic reviews in an outcome-centric manner. Herein we summarize the methods and lessons learned from conducting 4 outcome-centric overviews to help inform the Canadian 24-Hour Movement Guidelines for Adults aged 18–64 years and Adults aged 65 years or older on the topics of resistance training, balance and functional training, sedentary behaviour, sleep duration. We defined “critical” and “important” outcomes a priori. We used AMSTAR 2 to assess review quality and sought 1 systematic review per outcome. If multiple reviews were required to address subgroups for an outcome, we calculated the corrected covered area (CCA) to quantify overlap. We report our methodology in a PRISMA table. Across the 4 overviews, authors reviewed 1110 full texts; 45 were retained (low to high quality per AMSTAR 2), representing 950 primary studies, enrolling over 5 385 500 participants. Of 46 outcomes, we identified data for 35. Nineteen outcomes required >1 review (CCA range: 0% to 71.4%). Our outcome-centric overviews addressed unique aspects of overviews, including selection and quality assessment of included reviews, and overlap. Lessons learned included consistent application of methodological principles to minimize bias and optimize reporting transparency.

Novelty Overviews of reviews synthesize systematic reviews in a rigorous and transparent manner. Outcome-centric systematic reviews assess the quality of evidence for primary studies contributing to an outcome. This manuscript describes the development and application of extending the concept of outcome-centric systematic reviews to the design and conduct of outcome-centric overviews.

Sleep duration and health in adults: an overview of systematic reviews

The objective of this overview of systematic reviews was to examine the associations between sleep duration and health outcomes in adults. Four electronic databases were searched in December 2018 for systematic reviews published in the previous 10 years. Included reviews met the a priori determined population (community-dwelling adults aged 18 years and older), intervention/exposure/comparator (various levels of sleep duration), and outcome criteria (14 outcomes examined). To avoid overlap in primary studies, we used a priority list to choose a single review per outcome; reviews that examined the effect of age and those that looked at dose–response were prioritized. A total of 36 systematic reviews were eligible and 11 were included. Reviews included comprised 4 437 101 unique participants from 30 countries. Sleep duration was assessed subjectively in 96% of studies and 78% of studies in the reviews were prospective cohort studies. The dose–response curves showed that the sleep duration that was most favourably associated with health was 7–8 h per day. Modification of the effect by age was not apparent. The quality of the evidence ranged from low to high across health outcomes. In conclusion, the available evidence suggests that a sleep duration of 7–8 h per day is the one most favourably associated with health among adults and older adults. (PROSPERO registration no.: CRD42019119529.)

Novelty This is the first overview of reviews that examines the influence of sleep duration on a wide range of health outcomes in adults. Seven to 8 h of sleep per day was most favourably associated with health. Effect modification by age was not evident.

Repeated Application of a Novel Creatine Cream Improves Muscular Peak and Average Power in Male Subjects

Whinton, AK, Donahoe, K, Gao, R, Thompson, KMA, Aubry, R, Saunders, TJ, Johnston, A, Chilibeck, PD, and Burr, JF. Repeated application of a novel creatine cream improves muscular peak and average power in male subjects. J Strength Cond Res 34(9): 2482-2491, 2020-Using a multicenter, randomized controlled trial, (N = 123, age 23 ± 4 years) we sought to determine whether administration of a novel, topical creatine supplement could improve muscular performance after acute and repeated (7-day) exposure. To study the acute performance enhancing effects of the supplement, subjects completed 5 sets of 15 maximal concentric single-leg knee extensions with and without the application of a low- (low dose [LD]-3.5 ml) or high-dose (high dose [HD]-7 ml) topical creatine cream. After a wash-out period, subjects had one leg randomized to receive either the creatine or placebo cream, with further randomization into an oral creatine or placebo supplement group. Subjects completed 5 sets of 15 maximal concentric single leg knee extensions before and after the supplementation protocol. After acute application, no significant differences in peak power (LD: 252 ± 93 W, HD: 261 ± 100 W, p = 0.21), average power (LD: 172 ± 65 W, HD: 177 ± 69 W, p = 0.78), or fatigue index (LD: 13.4 ± 10.6%, HD: 14 ± 11.9%, p = 0.79) were observed between experimental and placebo creams (peak power: LD: 244 ± 76 W, HD: 267 ± 109 W; average power: LD: 168 ± 57 W, HD: 177 ± 67 W; fatigue index: LD: 12.4 ± 9.6%, HD: 12.8 ± 10.6%) or when controlling for sex. After the 7-day supplementation protocol, a significant increase in average power (creatine: 203 ± 61-220 ± 65 W, placebo: 224 ± 61-214 ± 61 W) and peak power (creatine: 264 ± 73-281 ± 80 W, placebo: 286 ± 79-271 ± 73 W) in the leg receiving creatine cream was observed in male subjects. No differences were observed in female subjects. The topical creatine cream did not enhance measures of muscle performance after acute application, but was able to improve peak and average power in male subjects after 7 consecutive days of application.

Combinations of physical activity, sedentary time, and sleep duration and their associations with depressive symptoms and other mental health problems in children and adolescents: a systematic review

Background

For optimal health benefits, the Canadian 24-Hour Movement Guidelines for Children and Youth (aged 5–17 years) recommend an achievement of high levels of physical activity (≥60 min of moderate-to-vigorous physical activity), low levels of sedentary behaviour (≤2 h of recreational screen time), and sufficient sleep (9–11 h for children or 8–10 h for adolescents) each day. The objective of this systematic review was to examine how combinations of physical activity, sedentary time, and sleep duration relate to depressive symptoms and other mental health indicators among children and adolescents.

Methods

Literature was obtained through searching Medline, EMBASE, PsycINFO, and SportDiscus up to September 30, 2019. Peer-reviewed studies published in English or French were included if they met the following criteria: population (apparently healthy children and adolescents with a mean age of 5–17 years), intervention/exposure (combinations of physical activity, sedentary time, and sleep duration), and outcomes (depressive symptoms and other mental health indicators). A risk of bias assessment was completed for all included studies using the methods described in the Cochrane Handbook. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework was used to assess the quality of evidence for each health indicator. Narrative syntheses were employed to describe the results due to high levels of heterogeneity across studies.

Results

A total of 13 cross-sectional studies comprised in 10 papers met inclusion criteria. Data across studies involved 115,540 children and adolescents from 12 countries. Overall, the findings indicated favourable associations between meeting all 3 recommendations and better mental health indicators among children and adolescents when compared with meeting none of the recommendations. There was evidence of a dose-response gradient between an increasing number of recommendations met and better mental health indicators. Meeting the screen time and sleep duration recommendations appeared to be associated with more mental health benefits than meeting the physical activity recommendation. The quality of evidence reviewed was “very low” according to GRADE.

Conclusions

The findings indicate favourable associations between meeting all 3 movement behaviour recommendations in the 24-h guidelines and better mental health indicators among children and adolescents. There is a clear need for high-quality studies that use robust measures of all movement behaviours and validated measures of mental health to increase our understanding in this topic area.

Combinations of physical activity and screen time recommendations and their association with overweight/obesity in adolescents

OBJECTIVES

To examine the four possible combinations of adherence to physical activity and screen time recommendations in adolescents and how the combinations relate to overweight and obesity.

METHODS

A total of 9913 students in grades 7-12 were included in the present cross-sectional analyses. Moderate-to-vigorous physical activity (MVPA), screen time, and body mass index were self-reported. Multivariate logistic regression analysis was used to test the associations between combinations of MVPA (≥ 60 min/day [active] or < 60 min/day [inactive]) and screen time (≤ 2 h/day [not sedentary] or > 2 h/day [sedentary]) recommendations with overweight/obesity.

RESULTS

We found that 53.1% of students in Ontario were considered "inactive+sedentary", 23.7% were considered "inactive+not sedentary", 12.1% were considered "active+sedentary", and 11.1% were considered "active+not sedentary". Some characteristics of "active+not sedentary" students (optimal category) included younger age, male gender, white ethnicity, higher socio-economic status, optimal sleep duration, and lower prevalence of cannabis use. After adjusting for relevant covariates, the "inactive+sedentary" group was more likely to report overweight/obesity than the "active+not sedentary" group (odds ratio [OR] = 1.71, 95% confidence interval [CI] = 1.26-2.32). The "inactive+not sedentary" group was also more likely to report overweight/obesity (OR = 1.54, 95% CI 1.20-1.97) while the "active+sedentary" group was not significantly associated with overweight/obesity (OR = 1.27, 95% CI 0.88-1.83).

CONCLUSION

Children meeting both the physical activity and screen time recommendations are less likely to be classified as overweight/obese compared with any other combination. Future efforts are needed to target both MVPA and sedentary behaviour to address public health concerns such as excess weight.

A comparison of self-reported and device measured sedentary behaviour in adults: a systematic review and meta-analysis

BACKGROUND

Sedentary behaviour (SB) is a risk factor for chronic disease and premature mortality. While many individual studies have examined the reliability and validity of various self-report measures for assessing SB, it is not clear, in general, how self-reported SB (e.g., questionnaires, logs, ecological momentary assessments (EMAs)) compares to device measures (e.g., accelerometers, inclinometers).

OBJECTIVE

The primary objective of this systematic review was to compare self-report versus device measures of SB in adults.

METHODS

Six bibliographic databases were searched to identify all studies which included a comparable self-report and device measure of SB in adults. Risk of bias within and across studies was assessed. Results were synthesized using meta-analyses.

RESULTS

The review included 185 unique studies. A total of 123 studies comprising 173 comparisons and data from 55,199 participants were used to examine general criterion validity. The average mean difference was -105.19 minutes/day (95% CI: -127.21, -83.17); self-report underestimated sedentary time by ~1.74 hours/day compared to device measures. Self-reported time spent sedentary at work was ~40 minutes higher than when assessed by devices. Single item measures performed more poorly than multi-item questionnaires, EMAs and logs/diaries. On average, when compared to inclinometers, multi-item questionnaires, EMAs and logs/diaries were not significantly different, but had substantial amount of variability (up to 6 hours/day within individual studies) with approximately half over-reporting and half under-reporting. A total of 54 studies provided an assessment of reliability of a self-report measure, on average the reliability was good (ICC = 0.66).

CONCLUSIONS

Evidence from this review suggests that single-item self-report measures generally underestimate sedentary time when compared to device measures. For accuracy, multi-item questionnaires, EMAs and logs/diaries with a shorter recall period should be encouraged above single item questions and longer recall periods if sedentary time is a primary outcome of study. Users should also be aware of the high degree of variability between and within tools. Studies should exert caution when comparing associations between different self-report and device measures with health outcomes.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42019118755.

Developing content for national population health surveys: an example using a newly developed sedentary behaviour module

Background

While physical (in) activity surveillance has grown and continues to grow globally, surveillance of sedentary behaviour is in its infancy. As surveillance evolves to meet the changing nature of these behaviours, there is a need for the development of national health survey questions to provide accurate and consistent measures over time. The development of national health survey content is a complex, detailed and often undocumented process. The objective of this paper is to outline the process that the Public Health Agency of Canada (PHAC) and Statistics Canada took in partnership with academic experts to develop a short, flexible, sedentary behaviour module for the Canadian Health Measures Survey (CHMS) and to provide an approach for the development of future survey content.

Methods

Development of the module followed a multi-step process. The results of this paper describe this process and present a framework for content development.

Results

Initially, PHAC and Statistics Canada analysts worked together to identify key content required for a potential survey module. Next, this work was formalized through a contract with academic experts, the scope included a: review of existing Canadian sedentary behaviour modules; literature review linking different sedentary behaviours to health outcomes; and, international scan of modules currently in use in large national health surveys and research. The key output from both review processes was recommendations for a short sedentary behaviour questionnaire module (International Sedentary Assessment Tool). These recommendations provided an evidence-informed basis for discussions about how to revise and update the CHMS sedentary behaviour questionnaire content. Qualitative testing was undertaken and a final module was developed using survey design best practices.

Conclusions

Content volume in national surveys is limited due to demand to measure core content in addition to emerging health topics while keeping surveys as short as possible. Questions must therefore, be concise, valid/reliable, evidence-based, and developed using best practices. The paper describes the development process of a new survey module addressing the emerging area of sedentary behaviour for use in a national survey that may serve as a model for future population survey content development.

Scientific sinkhole: The pernicious price of formatting

Objective

To conduct a time-cost analysis of formatting in scientific publishing.

Design

International, cross-sectional study (one-time survey).

Setting

Internet-based self-report survey, live between September 2018 and January 2019.

Participants

Anyone working in research, science, or academia and who submitted at least one peer-reviewed manuscript for consideration for publication in 2017. Completed surveys were available for 372 participants from 41 countries (60% of respondents were from Canada).

Main outcome measure

Time (hours) and cost (wage per hour x time) associated with formatting a research paper for publication in a peer-reviewed academic journal.

Results

The median annual income category was US$61,000–80,999, and the median number of publications formatted per year was four. Manuscripts required a median of two attempts before they were accepted for publication. The median formatting time was 14 hours per manuscript, or 52 hours per person, per year. This resulted in a median calculated cost of US$477 per manuscript or US$1,908 per person, per year.

Conclusions

To our knowledge, this is the first study to analyze the cost of manuscript formatting in scientific publishing. Our results suggest that scientific formatting represents a loss of 52 hours, costing the equivalent of US$1,908 per researcher per year. These results identify the hidden and pernicious price associated with scientific publishing and provide evidence to advocate for the elimination of strict formatting guidelines, at least prior to acceptance.

Cardiorespiratory fitness is associated with physical literacy in a large sample of Canadian children aged 8 to 12 years

BACKGROUND

The associations between cardiorespiratory fitness (CRF) and physical literacy in children are largely unknown. The aim of this study was to assess the relationships between CRF, measured using the 20-m shuttle run test (20mSRT), and components of physical literacy among Canadian children aged 8-12 years.

METHODS

A total of 9393 (49.9% girls) children, with a mean (SD) age of 10.1 (±1.2) years, from a cross-sectional surveillance study were included for this analysis. The SRT was evaluated using a standardized 15 m or 20 m protocol. All 15 m SRTs were converted to 20mSRT values using a standardized formula. The four domains of physical literacy (Physical Competence, Daily Behaviour, Motivation and Confidence, and Knowledge and Understanding) were measured using the Canadian Assessment of Physical Literacy. Tertiles were identified for 20mSRT laps, representing low, medium, and high CRF for each age and gender group. Cohen's d was used to calculate the effect size between the low and high CRF groups.

RESULTS

CRF was strongly and favourably associated with all components of physical literacy among school-aged Canadian children. The effect size between low and high CRF tertile groups was large for the Physical Competence domain (Cohen's d range: 1.11-1.94) across age and gender groups, followed by moderate to large effect sizes for Motivation and Confidence (Cohen's d range: 0.54-1.18), small to moderate effect sizes for Daily Behaviour (Cohen's d range: 0.25-0.81), and marginal to moderate effect sizes for Knowledge and Understanding (Cohen's d range: 0.08-0.70).

CONCLUSIONS

This study identified strong favourable associations between CRF and physical literacy and its constituent components in children aged 8-12 years. Future research should investigate the sensitivity and specificity of the 20mSRT in screening those with low physical literacy levels.

Associations between teacher training and measures of physical literacy among Canadian 8- to 12-year-old students

BACKGROUND

Quality physical education (PE) contributes to the development of physical literacy among children, yet little is known about how teacher training relates to this development. We assessed the association between teacher training, and the likelihood that children met recommended achievement levels for components of physical literacy as defined by the Canadian Assessment of Physical Literacy (CAPL).

METHODS

Canadian children (n = 4189; M = 10.72 years, SD = 1.19) from six provinces completed the CAPL. Logistic regression was used to examine the relationship between teacher training (generalist/PE specialist), adjusting for children's age and gender, and physical competence protocols (sit and reach, handgrip, plank, Progressive Aerobic Cardiovascular Endurance Run [PACER], body mass index [BMI], waist circumference, Canadian Agility and Movement Skill Assessment [CAMSA]), the four CAPL domain scores, and the total CAPL score.

RESULTS

Teacher training, in addition to children's age and gender, explained only a very small proportion of variance in each model (all R2 < 0.03). Children taught by a generalist were less likely to reach recommended levels of motivation and confidence (OR = 0.83, 95% CI, 0.72-0.95) or CAMSA scores (OR = 0.77, 95% CI, 0.67-0.90), even when accounting for a significant increase in CAMSA score with age (OR = 1.18, 95% CI, 1.12-1.26). All other associations between measures of components of physical literacy and teacher training were not significant.

CONCLUSIONS

While teacher training is hypothesized to contribute to the development of physical literacy among elementary school students, the observed effects in this study were either small or null. Children taught by PE specialists were more likely than those taught by generalists to demonstrate recommended levels of motivation and confidence, and to have better movement skills, which are hypothesized to be critical prerequisites for the development of a healthy lifestyle. Further research with more robust designs is merited to understand the impact of teachers' training on the various components of physical literacy development.

The relationship between sedentary behaviour and physical literacy in Canadian children: a cross-sectional analysis from the RBC-CAPL Learn to Play study

BACKGROUND

Physical literacy is the foundation of a physically active lifestyle. Sedentary behaviour displays deleterious associations with important health indicators in children. However, the association between sedentary behaviour and physical literacy is unknown. The purpose of this study was to identify the aspects of physical literacy that are associated with key modes of sedentary behaviour among Canadian children participating in the RBC-CAPL Learn to Play study.

METHODS

A total of 8,307 children aged 8.0-12.9 years were included in the present analysis. Physical literacy was assessed using the Canadian Assessment of Physical Literacy, which measures four domains (Physical Competence, Daily Behaviour, Motivation and Confidence, Knowledge and Understanding). Screen-based sedentary behaviours (TV viewing, computer and video game use), non-screen sedentary behaviours (reading, doing homework, sitting and talking to friends, drawing, etc.) and total sedentary behaviour were assessed via self-report questionnaire. Linear regression models were used to determine significant (p<0.05) correlates of each mode of sedentary behaviour.

RESULTS

In comparison to girls, boys reported more screen time (2.7±2.0 vs 2.2±1.8 hours/day, Cohen's d=0.29), and total sedentary behaviour (4.3±2.6 vs 3.9±2.4 hours/day, Cohen's d=0.19), but lower non-screen-based sedentary behaviour (1.6±1.3 vs 1.7±1.3 hours/day, Cohen's d=0.08) (all p< 0.05). Physical Competence (standardized β's: -0.100 to -0.036, all p<0.05) and Motivation and Confidence (standardized β's: -0.274 to -0.083, all p<0.05) were negatively associated with all modes of sedentary behaviour in fully adjusted models. Knowledge and Understanding was negatively associated with screen-based modes of sedentary behaviour (standardized β's: -0.039 to -0.032, all p<0.05), and positively associated with non-screen sedentary behaviour (standardized β: 0.098, p<0.05). Progressive Aerobic Cardiovascular Endurance Run score and log-transformed plank score were negatively associated with all screen-based modes of sedentary behaviour, while the Canadian Agility and Movement Skill Assessment score was negatively associated with all modes of sedentary behaviour other than TV viewing (all p<0.05).

CONCLUSIONS

These results highlight differences in the ways that screen and non-screen sedentary behaviours relate to physical literacy. Public health interventions should continue to target screen-based sedentary behaviours, given their potentially harmful associations with important aspects of physical literacy.

The relationship between physical literacy scores and adherence to Canadian physical activity and sedentary behaviour guidelines

BACKGROUND

Physical literacy is an emerging construct in children's health promotion, and may impact their lifelong physical activity habits. However, recent data reveal that only a small portion of Canadian children are regularly physically active and/or meet sedentary behaviour guidelines. To our knowledge, no study has investigated the association between physical literacy and movement behaviour guidelines. Therefore, the purpose of this study was to examine the relationship between physical literacy scores in Canadian children who meet or do not meet physical activity and sedentary behaviour guidelines.

METHODS

Children (n = 2956; 56.6% girls) aged 8-12 years from 10 Canadian cities had their physical literacy levels measured using the Canadian Assessment of Physical Literacy, which consists of four domains (Physical Competence; Daily Behaviour; Knowledge and Understanding; and Motivation and Confidence) that are aggregated to provide a composite physical literacy score. Physical activity levels were measured by pedometers, and sedentary behaviour was assessed through self-report questionnaire. Analyses were conducted separately for each guideline, comparing participants meeting versus those not meeting the guidelines. Comparisons were performed using MANOVA and logistic regression to control for age, gender, and seasonality.

RESULTS

Participants meeting physical activity guidelines or sedentary behaviour guidelines had higher physical literacy domain scores for Physical Competence and for Motivation and Confidence compared to those not meeting either guideline (both p < 0.0001). Participants had increased odds of meeting physical activity guidelines and sedentary behaviour guidelines if they met the minimum recommended level of the Physical Competence and Motivation and Confidence domains. Significant age (OR 0.9; 95% CI: 0.8, 0.9), gender (OR 0.4; 95% CI: 0.3, 0.5) and seasonality effects (OR 1.6; 95% CI: 1.2, 2.2 spring and OR 1.7; 95% CI: 1.2, 2.5 summer, reference winter) were seen for physical activity guidelines, and age (OR 0.8; 95% CI: 0.7, 0.8) and gender effects (OR 1.7; 95% CI: 1.4, 2.0) for sedentary behaviour guidelines. Knowledge and Understanding of physical activity principles was not related to guideline adherence in either model.

CONCLUSIONS

These cross-sectional findings demonstrate important associations between physical literacy and guideline adherence for physical activity and sedentary behaviour. Future research should explore the causality of these associations.

A cross-sectional study exploring the relationship between age, gender, and physical measures with adequacy in and predilection for physical activity

BACKGROUND

Physical literacy is a complex construct influenced by a range of physical, behavioural, affective, and cognitive factors. Researchers are interested in relationships among these constituent factors. The purpose of this study was to investigate how age, gender, and physical competence components of physical literacy relate to a child's adequacy in and predilection for physical activity.

METHODS

A sample of 8530 Canadian youth (50% girl) aged 8.0 to 12.9 years participated in the study. Participants completed the Canadian Assessment of Physical Literacy (CAPL) protocol, which assesses physical literacy in four domains: Physical Competence, Daily Behaviour, Motivation and Confidence, and Knowledge and Understanding. Stepwise multiple regression analyses were conducted to investigate the relationship between physical competence components of physical literacy (Progressive Aerobic Cardiovascular Endurance Run [PACER], Canadian Agility and Movement Skill Assessment [CAMSA], sit and reach, handgrip, plank, and body mass index) and children's perceived adequacy and predilection toward physical activity as measured by subscales from the Children's Self-Perceptions of Adequacy in and Predilection for Physical Activity scale (CSAPPA).

RESULTS

The variable most strongly associated with adequacy and predilection was the PACER shuttle run score. The PACER accounted for 10.9% of the variance in adequacy and 9.9% of the variance in predilection. Participants' age was inversely related to adequacy (β = - 0.374) and predilection (β = - 0.621). The combination of other variables related to adequacy brought the total variance explained to 14.7%, while the model for predilection explained a total of 13.7%.

CONCLUSIONS

Results indicate an association between cardiorespiratory fitness and measures of physical activity adequacy and predilection. These findings suggest that practitioners should consider the physiological and psychological makeup of the child, and ways to enhance adequacy and predilection among children with limited cardiorespiratory fitness, in order to create the best possible environment for all children to participate in physical activity.

Physical literacy levels of Canadian children aged 8-12 years: descriptive and normative results from the RBC Learn to Play-CAPL project

BACKGROUND

The current physical literacy level of Canadian children is unknown. The Royal Bank of Canada (RBC) Learn to Play - Canadian Assessment of Physical Literacy (CAPL) project, which is anchored in the Canadian consensus statement definition of physical literacy, aimed to help establish the current physical literacy level of Canadian children.

METHODS

The CAPL was used to assess the physical literacy (and component domains: Daily Behaviour, Physical Competence, Knowledge and Understanding, and Motivation and Confidence) of Canadian children aged 8-12 years. Data were collected from 11 sites across Canada, yielding a sample of 10,034 participants (5030 girls). Descriptive statistics by age and gender were calculated and percentile distributions of physical literacy scores, including each domain and individual measure, were derived.

RESULTS

The mean age of participants was 10.1 ± 1.2 years. Total physical literacy scores (out of 100) were on average 63.1 ± 13.0 for boys and 62.2 ± 11.3 for girls. For boys and girls respectively, domain scores were 19.9 ± 4.7 and 19.3 ± 4.1 (out of 32) for Physical Competence; 18.6 ± 7.9 and 18.5 ± 7.4 (out of 32) for Daily Behaviour; 12.7 ± 2.8 and 12.2 ± 2.6 (out of 18) for Motivation and Confidence; and 11.8 ± 2.8 and 12.2 ± 2.6 (out of 18) for Knowledge and Understanding. Physical Competence measures were on average 28.1 ± 8.4 cm (sit-and-reach flexibility), 33.5 ± 9.4 kg (grip strength, right + left), 23.4 ± 14.1 laps (Progressive Aerobic Cardiovascular Endurance Run [PACER] shuttle run), 61.8 ± 43.8 s (isometric plank), 19.0 ± 3.8 kg/m2 (body mass index), 67.3 ± 10.8 cm (waist circumference), and 20.6 ± 3.9 out of 28 points for the Canadian Agility and Movement Skill Assessment (CAMSA), with scores for boys higher than girls and older children higher than younger children for grip strength, PACER, plank, and CAMSA score. Girls and younger children had better scores on the sit-and-reach flexibility than boys and older children. Daily pedometer step counts were higher in boys than girls (12,355 ± 4252 vs. 10,779 ± 3624), and decreased with age.

CONCLUSIONS

These results provide the largest and most comprehensive assessment of physical literacy of Canadian children to date, providing a "state of the nation" baseline, and can be used to monitor changes and inform intervention strategies going forward.

Measurement of sedentary behaviour in population health surveys: a review and recommendations

Background

The purpose of this review was to determine the most valid and reliable questions for targeting key modes of sedentary behaviour (SB) in a broad range of national and international health surveillance surveys. This was done by reviewing the SB modules currently used in population health surveys, as well as examining SB questionnaires that have performed well in psychometric testing.

Methods

Health surveillance surveys were identified via scoping review and contact with experts in the field. Previous systematic reviews provided psychometric information on pediatric questionnaires. A comprehensive search of four bibliographic databases was used to identify studies reporting psychometric information for adult questionnaires. Only surveys/studies published/used in English or French were included.

Results

The review identified a total of 16 pediatric and 18 adult national/international surveys assessing SB, few of which have undergone psychometric testing. Fourteen pediatric and 35 adult questionnaires with psychometric information were included. While reliability was generally good to excellent for questions targeting key modes of SB, validity was poor to moderate, and reported much less frequently. The most valid and reliable questions targeting specific modes of SB were combined to create a single questionnaire targeting key modes of SB.

Discussion

Our results highlight the importance of including SB questions in survey modules that are adaptable, able to assess various modes of SB, and that exhibit adequate reliability and validity. Future research could investigate the psychometric properties of the module we have proposed in this paper, as well as other questionnaires currently used in national and international population health surveys.

Sedentary Behavior Research Network (SBRN) - Terminology Consensus Project process and outcome

BACKGROUND

The prominence of sedentary behavior research in health science has grown rapidly. With this growth there is increasing urgency for clear, common and accepted terminology and definitions. Such standardization is difficult to achieve, especially across multi-disciplinary researchers, practitioners, and industries. The Sedentary Behavior Research Network (SBRN) undertook a Terminology Consensus Project to address this need.

METHOD

First, a literature review was completed to identify key terms in sedentary behavior research. These key terms were then reviewed and modified by a Steering Committee formed by SBRN. Next, SBRN members were invited to contribute to this project and interested participants reviewed and provided feedback on the proposed list of terms and draft definitions through an online survey. Finally, a conceptual model and consensus definitions (including caveats and examples for all age groups and functional abilities) were finalized based on the feedback received from the 87 SBRN member participants who responded to the original invitation and survey.

RESULTS

Consensus definitions for the terms physical inactivity, stationary behavior, sedentary behavior, standing, screen time, non-screen-based sedentary time, sitting, reclining, lying, sedentary behavior pattern, as well as how the terms bouts, breaks, and interruptions should be used in this context are provided.

CONCLUSION

It is hoped that the definitions resulting from this comprehensive, transparent, and broad-based participatory process will result in standardized terminology that is widely supported and adopted, thereby advancing future research, interventions, policies, and practices related to sedentary behaviors.

Canadian Agility and Movement Skill Assessment (CAMSA): Validity, objectivity, and reliability evidence for children 8-12 years of age

PURPOSE

The primary aim of this study was to develop an assessment of the fundamental, combined, and complex movement skills required to support childhood physical literacy. The secondary aim was to establish the feasibility, objectivity, and reliability evidence for the assessment.

METHODS

An expert advisory group recommended a course format for the assessment that would require children to complete a series of dynamic movement skills. Criterion-referenced skill performance and completion time were the recommended forms of evaluation. Children, 8-12 years of age, self-reported their age and gender and then completed the study assessments while attending local schools or day camps. Face validity was previously established through a Delphi expert (n = 19, 21% female) review process. Convergent validity was evaluated by age and gender associations with assessment performance. Inter- and intra-rater (n = 53, 34% female) objectivity and test-retest (n = 60, 47% female) reliability were assessed through repeated test administration.

RESULTS

Median total score was 21 of 28 points (range 5-28). Median completion time was 17 s. Total scores were feasible for all 995 children who self-reported age and gender. Total score did not differ between inside and outside environments (95% confidence interval (CI) of difference: -0.7 to 0.6; p = 0.91) or with/without footwear (95%CI of difference: -2.5 to 1.9; p = 0.77). Older age (p < 0.001, η 2 = 0.15) and male gender (p < 0.001, η 2 = 0.02) were associated with a higher total score. Inter-rater objectivity evidence was excellent (intraclass correlation coefficient (ICC) = 0.99) for completion time and substantial for skill score (ICC = 0.69) for 104 attempts by 53 children (34% female). Intra-rater objectivity was moderate (ICC = 0.52) for skill score and excellent for completion time (ICC = 0.99). Reliability was excellent for completion time over a short (2-4 days; ICC = 0.84) or long (8-14 days; ICC = 0.82) interval. Skill score reliability was moderate (ICC = 0.46) over a short interval, and substantial (ICC = 0.74) over a long interval.

CONCLUSION

The Canadian Agility and Movement Skill Assessment is a feasible measure of selected fundamental, complex and combined movement skills, which are an important building block for childhood physical literacy. Moderate-to-excellent objectivity was demonstrated for children 8-12 years of age. Test-retest reliability has been established over an interval of at least 1 week. The time and skill scores can be accurately estimated by 1 trained examiner.

Screen Time and Health Indicators Among Children and Youth: Current Evidence, Limitations and Future Directions

Despite accumulating evidence linking screen-based sedentary behaviours (i.e. screen time) with poorer health outcomes among children and youth <18 years of age, the prevalence of these behaviours continues to increase, with roughly half of children and youth exceeding the public health screen time recommendation of 2 h per day or less. The purpose of this article is to provide an overview of key research initiatives aimed at understanding the associations between screen time and health indicators including physical health, quality of life and psychosocial health. Available evidence suggests that screen time is deleteriously associated with numerous health indicators in child and youth populations, including adiposity, aerobic fitness, quality of life, self-esteem, pro-social behaviour, academic achievement, depression and anxiety. However, few longitudinal or intervention studies have been conducted, with most of these studies focusing on physical health indicators. While most studies have used self-reported assessments of screen time, the availability of more objective assessment methods presents important opportunities (e.g. more accurate and precise assessment of sedentary time and screen time) and challenges (e.g. privacy and participant burden). Novel statistical approaches such as isotemporal substitution modelling and compositional analysis, as well as studies using longitudinal and experimental methodologies, are needed to better understand the health impact of excessive screen time, and to develop strategies to minimise or reverse the negative impacts of these behaviours. The evidence to date suggests a clear need for policy aimed at minimising the hazardous health consequences associated with screen time among children and youth.

Interactions between sleep, movement and other non-movement behaviours in the pathogenesis of childhood obesity

Research examining the health effects of physical activity, sedentary behaviour and sleep on different health outcomes has largely been conducted independently or in isolation of the other behaviours. However, the fact that time is finite (i.e. 24 h) suggests that the debate on whether or not the influence of a single behaviour is independent of another one is conceptually incorrect. Time spent in one behaviour should naturally depend on the composition of the rest of the day. Recent evidence using more appropriate analytical approaches to deal with this methodological issue shows that the combination of sleep, movement and non-movement behaviours matters and all components of the 24-h movement continuum should be targeted to enhance health and prevent childhood obesity. The objective of this review is to discuss research investigating how combinations of physical activity, sedentary behaviour and sleep are related to childhood obesity. Emerging statistical approaches (e.g. compositional data analysis) that can provide a good understanding of the best 'cocktail' of behaviours associated with lower adiposity and improved health are also discussed. Finally, future research directions are provided. Collectively, it becomes clearer that guidelines and public health interventions should target all movement behaviours synergistically to optimize health of children and youth around the world.

Canadian 24-Hour Movement Guidelines for Children and Youth: An Integration of Physical Activity, Sedentary Behaviour, and Sleep

Leaders from the Canadian Society for Exercise Physiology convened representatives of national organizations, content experts, methodologists, stakeholders, and end-users who followed rigorous and transparent guideline development procedures to create the Canadian 24-Hour Movement Guidelines for Children and Youth: An Integration of Physical Activity, Sedentary Behaviour, and Sleep. These novel guidelines for children and youth aged 5-17 years respect the natural and intuitive integration of movement behaviours across the whole day (24-h period). The development process was guided by the Appraisal of Guidelines for Research Evaluation (AGREE) II instrument and systematic reviews of evidence informing the guidelines were assessed using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. Four systematic reviews (physical activity, sedentary behaviour, sleep, integrated behaviours) examining the relationships between and among movement behaviours and several health indicators were completed and interpreted by expert consensus. Complementary compositional analyses were performed using Canadian Health Measures Survey data to examine the relationships between movement behaviours and health indicators. A stakeholder survey was employed (n = 590) and 28 focus groups/stakeholder interviews (n = 104) were completed to gather feedback on draft guidelines. Following an introductory preamble, the guidelines provide evidence-informed recommendations for a healthy day (24 h), comprising a combination of sleep, sedentary behaviours, light-, moderate-, and vigorous-intensity physical activity. Proactive dissemination, promotion, implementation, and evaluation plans have been prepared in an effort to optimize uptake and activation of the new guidelines. Future research should consider the integrated relationships among movement behaviours, and similar integrated guidelines for other age groups should be developed.

Sedentary behaviours among adults across Canada

OBJECTIVES: While cross-Canada variations in physical activity and weight status have been illustrated, less is known about sedentary behaviour (SB). The aim of this study was to describe various SBs and their correlates among Canadian adults. METHODS: Cross-sectional data from the 2011-2012 Canadian Community Health Survey included 92,918 respondents aged 20-75+ years, representative of &gt;22 million Canadian adults. TV/video viewing, computer, video game playing and reading time were self-reported. Associations with socio-demographic, health and health behaviour variables were examined. RESULTS: About 31% of adults reported &gt;2 hours/day TV viewing, while 47% of men and 41% of women reported &gt;5 hours/week computer use, 24% of men and 12% of women reported ≥1 hour/week video game playing, and 33% of men and 46% of women reported &gt;5 hours/week reading; 28% of respondents reported ≥5 hours/day total SB time. Age was the strongest correlate: adults 75+ had 5 and 6 times greater odds respectively of reporting &gt;2 hours/day TV viewing and &gt;5 hours/week reading, but far lesser odds of reporting high computer or video game time, compared to adults 20-24. Other variables associated with specific SBs included gender, marital status, education, occupation, income and immigrant status, as well as BMI, weight perceptions, smoking, diet and physical activity. CONCLUSION: Common sedentary behaviours were associated with numerous socio-demographic, health and health behaviour characteristics in a large representative sample of Canadians. These correlates differed according to the type of SB. Public health interventions targeting SB should be behavior-specific and tailored to the population segment of interest.

Systematic review of sedentary behaviour and health indicators in school-aged children and youth: an update

This systematic review is an update examining the relationships between objectively and subjectively measured sedentary behaviour and health indicators in children and youth aged 5–17 years. EMBASE, PsycINFO, and Medline were searched in December 2014, and date limits were imposed (≥February 2010). Included studies were peer-reviewed and met the a priori-determined population (apparently healthy children and youth, mean age: 5–17 years), intervention (durations, patterns, and types of sedentary behaviours), comparator (various durations, patterns, and types of sedentary behaviours), and outcome (critical: body composition, metabolic syndrome/cardiovascular disease risk factors, behavioural conduct/pro-social behaviour, academic achievement; important: fitness, self-esteem) study criteria. Quality of evidence by outcome was assessed using the Grading of Recommendations Assessment, Development, and Evaluation framework. Due to heterogeneity, a narrative analysis was conducted. A total of 235 studies (194 unique samples) were included representing 1 657 064 unique participants from 71 different countries. Higher durations/frequencies of screen time and television (TV) viewing were associated with unfavourable body composition. Higher duration/frequency of TV viewing was also associated with higher clustered cardiometabolic risk scores. Higher durations of TV viewing and video game use were associated with unfavourable behavioural conduct/pro-social behaviour. Higher durations of reading and doing homework were associated with higher academic achievement. Higher duration of screen time was associated with lower fitness. Higher durations of screen time and computer use were associated with lower self-esteem. Evidence ranged from “very low” to “moderate” quality. Higher quality studies using reliable and valid sedentary behaviour measures should confirm this largely observational evidence.

Sit less, stand more: A randomized point-of-decision prompt intervention to reduce sedentary time

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.

Workplace standing time and the incidence of obesity and type 2 diabetes: a longitudinal study in adults

Background

It is increasingly recognized that standing represents a simple solution to extended periods of sitting. However, it is currently unknown whether workplace standing time is prospectively associated with a lower incidence of chronic diseases. The objective of this study was to examine the association between workplace standing time and the incidence of overweight/obesity (OW/OB) and impaired glucose tolerance/type 2 diabetes (IGT/T2D) in adults.

Methods

A longitudinal analysis from the Quebec Family Study (Canada) was conducted on 293 participants, aged 18 to 65 years, followed for a mean of 6 years. Information on self-reported occupational standing time as well as several covariates was collected at both baseline and follow-up. Outcome measures included the development of OW/OB (i.e. body mass index ≥25 kg/m²) and IGT/T2D (i.e. 2-h postload plasma glucose level ≥7.8 mmol/L).

Results

The incidence rates of OW/OB and IGT/T2D over the 6-year follow-up period were 17.4% and 12.6%, respectively. Significant negative associations were observed between the amount of occupational standing time and the development of outcome measures. However, the associations were no longer significant after adjustment for age, sex, smoking habits, total annual family income, daily caloric intake, and submaximal working capacity. In age- and sex-adjusted logistic regression analysis, significant negative linear trends were observed across levels of standing time and the outcome variables. However, the associations were no longer significant after further adjustment for the other covariates. Finally, we observed that the change in standing time from baseline to year 6 was significantly associated with the development of outcome measures, with higher incidence rates in adults reporting a reduction in standing time at follow-up. However, the associations became non-significant after adjustment for covariates.

Conclusions

Greater occupational standing time is not sufficient in and of itself to prevent the development of OW/OB and IGT/T2D in adults. Future efforts are needed to better understand the potential benefits of higher amounts of standing time throughout the day on the prevention of chronic diseases.