Associations of sedentary behavior, sedentary bouts and breaks in sedentary time with cardiometabolic risk in children with a family history of obesity

Early Lifestyle Determinants of Adiposity Trajectories from Childhood into Late Adolescence

Objective: The aim of this study was to examine associations of childhood physical activity, sedentary behavior, and dietary intake with adiposity trajectories from childhood to adolescence. Methods: Quebec Adipose and Lifestyle Investigation in Youth (QUALITY) cohort (n = 630) data from 3 time points (8-10, 10-12, and 15-17 years) for 377 Caucasian children with parental obesity were analyzed. Height and weight, physical activity and sedentary behavior (7-day accelerometry), screen time (self-reported), and dietary intake (three 24-hour diet recalls) were measured. Group-based trajectory modeling identified longitudinal trajectories of body-mass index z-scores (zBMIs). Inverse probability of exposure-weighted multinomial logistic regressions examined associations between baseline lifestyles and zBMI trajectory groups. Results: Six trajectory groups were identified: Stable-Low-Normal-Weight (two groups, 5.7% and 33.0%, which were combined), Stable-High-Normal-Weight (24.8%), Stable-Overweight (19.8%), Stable-Obesity (8.8%), and Overweight-Decreasers (7.9%). For every additional portion of fruits and vegetables, the likelihood of being in the group of Overweight-Decreasers increased by 29% (odds ratio [OR]: 1.29, 95% confidence interval [CI]: 1.09-1.55) compared with the reference group (Stable-Low-Normal-Weight). For every additional hour of sedentary behavior, the likelihood of belonging to the group of Overweight-Decreasers increased 2-fold (OR: 1.99, 95% CI: 1.28-3.21) and Stable-Obesity increased 1.5-fold (OR: 1.56, 95% CI: 1.08-2.23), compared with the reference. Every additional 10 minutes of moderate-to-vigorous physical activity was associated with a lower likelihood of belonging to the Stable-Obesity group (OR: 0.75, 95% CI: 0.61-0.89) and to the group of Overweight-Decreasers (OR: 0.79, 95% CI: 0.64-0.95) compared with the reference. Finally, children were more likely to belong to the Stable-Obesity group with each additional hour/day of screen time (OR: 1.23, 95% CI: 1.01-1.58). Conclusions: Trajectories of zBMIs from childhood to late adolescence were stable, except for one group which decreased from overweight in childhood to normal weight in adolescence. The latter had more favorable baseline dietary intake of fruits and vegetables. ClinicalTrials.org no. NCT03356262.

Sedentary time at school and work in Canada

OBJECTIVES

High levels of sedentary time (ST) are associated with poor physical and mental health. Given that Canadians spend a large portion of their days at school and work, they may be important targets for reducing ST. Our objectives are to estimate the daily amount of school and work ST among Canadians, examine differences by subgroups, and determine associations with health.

METHODS

Using the 2020 Canadian Community Health Survey Healthy Living Rapid Response module (N = 5242), the amount of time spent sitting while at school and work was estimated among youth (12-17 years) and adults (18-34 and 35-64 years). Differences by sociodemographics and 24-Hour Movement Guideline adherence were assessed with independent t-tests. Associations between school and work ST and health indicators were assessed using adjusted logistic regression.

RESULTS

Canadian youth aged 12-17 years and adults aged 18-34 years reported an average of 4.5 and 5.2 h/day of school ST, respectively. Adults 18-34 years and 35-64 years reported an average of 3.9 and 4.0 h/day of work ST, respectively. School and work ST differed within several subgroups. Among adults 18-34 years, higher school ST was associated with a reduced odds of 'excellent/very good' mental health, whereas higher work ST was associated with a greater likelihood of reporting 'excellent/very good' general health.

CONCLUSION

Canadian youth and working-age adults report an average of 4-5 h/day sedentary at school or work. This is the first study estimating school and work ST in a representative sample of Canadians and will aid in increasing awareness of setting-specific behaviours to better inform targeted interventions including addressing inequalities in ST.

The association of objectively measured sedentary time with asthma in US youth: A glimpse into the connection between obesity and asthma

BACKGROUND

Evidence suggests that asthma and obesity may share a common pathway, possibly through an increase in inflammation. Sedentary time is thought to promote both inflammation and obesity and previous studies have found a relationship between self-reported sedentary and asthma. However, the relationship between objectively measured sedentary time and asthma is not well described. We hypothesized that the association between asthma and sedentary time would not be present when physical activity was measured objectively, nor would objectively-measured sedentary time play an important role in the relationship between asthma and obesity.

OBJECTIVE

To determine if there is an association between asthma and objectively measured sedentary time in a large, nationally representative sample of the United States youth.

METHODS

Using the National Health and Nutrition Examination Survey 2003-2006, we assessed the relationship between asthma and sedentary time using objectively measured and self-reported measures of sedentary time, in 6-19 years-old subjects with available accelerometry data. We used multivariate logistic regression analysis to determine associations between the risk of asthma and sedentary time controlling for accelerometer wear time, gender, age, race/ethnicity, body mass index percentile, and moderate-to-vigorous physical activity (MVPA).

RESULTS

In this cohort, youth with asthma self-reported more time in sedentary behavior, specifically computer time, than those without asthma (p = 0.01). However, when sedentary time was measured objectively by accelerometry, sedentary time did not differ between youth with and without asthma (421 min [standard deviation 4.2] versus. 414 min [standard deviation 7.8] [p = 0.38]). Controlling for measures of activity, such as MVPA, or time spent in long versus short bouts of sedentary time did not modify our results.

CONCLUSIONS

Differences in sedentary time by self-report between those with and without asthma were not born out by examining sedentary time using objective measures. Further work is necessary to examine the complex interaction among inactivity, obesity, and asthma over time, specifically focusing on whether the type of sedentary activity (e.g., computer vs. television time) is important.

Meeting the WHO 24-h guidelines among 2-6-year-old children by family socioeconomic status before and during the COVID-19 pandemic: a repeated cross-sectional study

Background

The World Health Organization (WHO) has developed guidelines for 24-h physical activity (PA), sedentary behaviour and sleep for young children. Lower socioeconomic status (SES) has been linked to a lower likelihood of meeting these guidelines. The outbreak of the novel coronavirus disease (COVID-19) raised concerns about young children's opportunities to meet the guidelines. The study focused on the prevalence of meeting the WHO's 24-h guidelines on screen time (ST), PA and sleep among 2-6-year-old children, in association with family SES, before COVID-19 outbreak in 2019, and during the pandemic in 2020 and 2021 in Finland.

Methods

Data were collected at three timepoints by an online survey through day-care centres. Meeting the WHO 24-h guidelines was defined for each behaviour, from a parent-reported seven-day recall of a typical day on weekdays and weekend days and adapted to the national context. Children were considered to meet the ST guideline if they had maximum of 60 min of ST, the PA guideline if they had minimum of 60 min of outdoor PA, and the sleep guidelines if they had minimum of 11/10/9 h (2/3-5/6 years) of good or very good quality sleep. Binary logistic regression models were used to examine the odds ratios of meeting the guidelines.

Results

The prevalence of meeting the ST guideline was highest before the COVID-19 pandemic in 2019. The PA guideline was most met during the strict pandemic restrictions in 2020. Children from higher SES families were more likely to meet the ST and sleep duration guidelines either on weekdays or weekends. The PA guideline was met more on weekdays by children whose parents had lower education levels at all timepoints. In 2020, sleep quality guideline was less likely met by children with parents with the highest education levels.

Conclusion

Higher SES may increase the odds of young children meeting the ST and sleep duration guidelines, but the results are more complex regarding PA and SES. The impact of the COVID-19 pandemic on ST, outdoor PA, and sleep of young children varied by family SES, and further research is recommended to identify causality of these relationships.

Supplementary Information

The online version contains supplementary material available at 10.1186/s44167-022-00010-4.

A Systematic Review of the Associations of Adiposity and Cardiorespiratory Fitness With Arterial Structure and Function in Nonclinical Children and Adolescents

PURPOSE

To summarize the evidence on associations of adiposity and cardiorespiratory fitness (CRF) with arterial structure and function in nonclinical children and adolescents.

METHODS

Two researchers conducted a search in 5 electronic databases in April 2022 to find studies in nonclinical youth (age 5-17.9 y) reporting multivariable associations. Studies were eligible if adiposity and/or CRF were used as the predictor and arterial structure and/or function was the outcome. The Quality Assessment Tool for Quantitative Studies was used to assess methodological quality for experimental studies, and a modified version was used for observational studies.

RESULTS

Ninety-nine studies (72.7% cross-sectional) were included. Ninety-four assessed associations between adiposity and arterial outcomes, most using overall body proportion (n = 71), abdominal (n = 52), or whole-body adiposity (n = 40). Most evidence was inconsistent or nonsignificant, but 59 studies suggested higher abdominal adiposity and worse body proportion were associated with adverse arterial outcomes. Twenty-one assessed associations between CRF and arterial outcomes, with findings inconsistent. Most evidence was rated weak in quality.

CONCLUSION

While high adiposity may contribute to poor arterial outcomes, evidence is limited regarding CRF. Future studies should disentangle these associations by studying youth with healthy adiposity but poor CRF, or vice versa, using longitudinal or experimental study designs.

Sedentary Patterns and Sit-to-Stand Transitions in Open Learning Spaces and Conventional Classrooms among Primary School Students

Educational reforms worldwide have resulted in schools increasingly incorporating open and flexible classroom designs that may provide possibilities to reduce sedentary behavior among students during lessons. Cross-sectional associations of classroom type on accelerometry assessed sedentary bout durations and sit-to-stand transitions were investigated in 191 third and fifth grade students recruited from one school with open learning spaces and two schools with conventional classrooms. A three-way ANOVA for classroom type, gender and grade level indicated that students in open learning spaces had more 1-to-4-min sedentary bouts (mean difference 1.8 bouts/h, p < 0.001), fewer >10-min sedentary bouts (median 0.20 vs. 0.48 bouts/h, p = 0.004) and more sit-to-stand transitions (mean difference 0.9 STS/h, p = 0.009) than students in conventional learning spaces. Comparisons between schools by grade, which were conducted with a one-way ANCOVA adjusted for gender, indicated that most of the significant differences occurred between schools with different classroom types. There were only small and mostly statistically nonsignificant differences between the two schools with conventional classrooms. In conclusion, open learning spaces may improve children’s sedentary profiles towards shorter sedentary bout durations and facilitate also postural transitions during lessons, which may translate into beneficial health impacts over a longer period.

Sex Differences in Neuropeptide Y Serum, But Not in Fat Intake and Body Mass Index

Background:  One’s appetite has a role in controlling food intake and maintaining energy balance, but its effect on body metabolism related to obesity is still questionable. The purpose of this study was to determine the levels of neuropeptide Y in healthy people and to see differences in gender and anthropometric parameters. The hypothesis of this study was that there would be differences in neuropeptide Y levels in groups with gender and anthropometric parameter differences.      Methods:   This study was a cross-sectional study involving 62 study subjects, male and female, who did not have chronic diseases or metabolic disorders. This research was conducted from April to September 2020. The parameters examined in this study were neuropeptide Y levels and anthropometric parameters. The statistical analysis performed was the Mann–Whitney test to see the differences between groups.  Results:   The mean age of the research subjects was 40.48 ± 10.85 years, with the same ethnic distribution. The distribution of men and women was more women than men. Based on anthropometric examination, it was found that obesity nutritional status was more common in the female group than in the male group; however, serum neuropeptide Y levels were found to be significantly different between male and female groups (male group was higher) which were mean±standard deviation: 348.37±330.09 ng/L, p=0.036.  Conclusions: The study found significant differences in serum neuropeptide Y levels in male and female groups, with neuropeptide Y levels being higher in men than in women. 

Examining 24-Hour Activity and Sleep Behaviors and Related Determinants in Latino Adolescents and Young Adults With Obesity

Background. Few studies have examined 24-hour activity and sleep behaviors and their contribution to type 2 diabetes (T2D) in Latino adolescents and young adults with obesity. Aim. This study included quantitative data on T2D risk and 24-hour activity and sleep behaviors and qualitative data on individual, social, and environmental behavioral determinants. Method. A 7 day, 24-hour, wrist-worn accelerometer protocol assessed moderate-to-vigorous physical activity (PA), sedentary behaviors (SB), sleep, and sleep regularity, in adolescents (N = 38; 12-16 years) and young adults (N = 22; 18-22 years). T2D-related outcomes included adiposity (BMI, BF%, waist circumference), fasting, and 2-hour glucose. A subsample of participants (N = 16 adolescents, N = 15 young adults) completed interviews to identify behavioral determinants. Results. High levels of PA were observed among adolescents (M = 103.8 ± 67.5 minutes/day) and young adults (M = 96.8 ± 78.8 minutes/day) as well as high levels of SB across both age groups (≥10 hours/day). Sleep regularity was negatively associated with adiposity (all ps < .05) in both age groups as well as fasting and 2-hour glucose in young adults (all ps < .05). Social support was associated with PA in both age groups as well as SB in younger youth. Auditory noises, lights, and safety inhibited sleep in both age groups. Conclusion. PA is critical for disease reduction, yet reducing SB and improving sleep are also important targets for reducing T2D risk in Hispanic adolescents and young adults. Future health promotion and disease prevention strategies should leverage qualitative findings regarding behavioral determinants.

Impact of the COVID-19 Pandemic on Sedentary Time and Behaviour in Children and Adults: A Systematic Review and Meta-Analysis

The aim of this meta-analysis was to quantify the change in sedentary time during the COVID-19 pandemic and its effect on health outcomes in the general population. One thousand six hundred and one articles published after 2019 were retrieved from five databases, of which 64 and 40 were included in the systematic review and meta-analysis, respectively. Studies were grouped according to population: children (<18 years), adults (18–64 years) and older adults (>65 years). Average sedentary time was calculated, with sub-analyses performed by country, behaviour type and health outcomes. Children were most affected, increasing their sedentary time by 159.5 ± 142.6 min day⁻¹, followed by adults (+126.9 ± 42.2 min day⁻¹) and older adults (+46.9 ± 22.0 min day⁻¹). There were no sex differences in any age group. Screen time was the only consistently measured behaviour and accounted for 46.8% and 57.2% of total sedentary time in children and adults, respectively. Increases in sedentary time were negatively correlated with global mental health, depression, anxiety and quality of life, irrespective of age. Whilst lockdown negatively affected all age groups, children were more negatively affected than adults or older adults, highlighting this population as a key intervention target. As lockdowns ease worldwide, strategies should be employed to reduce time spent sedentary. Trial registration: PROSPERO (CRD42020208909).

Media use trajectories and risk of metabolic syndrome in European children and adolescents: the IDEFICS/I.Family cohort

Background

Media use may influence metabolic syndrome (MetS) in children. Yet, longitudinal studies are scarce. This study aims to evaluate the longitudinal association of childhood digital media (DM) use trajectories with MetS and its components.

Methods

Children from Belgium, Cyprus, Estonia, Germany, Hungary, Italy, Spain and Sweden participating in the IDEFICS/I.Family cohort were examined at baseline (W1: 2007/2008) and then followed-up at two examination waves (W2: 2009/2010 and W3: 2013/2014). DM use (hours/day) was calculated as sum of television viewing, computer/game console and internet use. MetS z-score was calculated as sum of age- and sex-specific z-scores of four components: waist circumference, blood pressure, dyslipidemia (mean of triglycerides and HDL-cholesterol⁻¹) and homeostasis model assessment for insulin resistance (HOMA-IR). Unfavorable monitoring levels of MetS and its components were identified (cut-off: ≥ 90^th percentile of each score). Children aged 2–16 years with ≥ 2 observations (W1/W2; W1/W3; W2/W3; W1/W2/W3) were eligible for the analysis. A two-step procedure was conducted: first, individual age-dependent DM trajectories were calculated using linear mixed regressions based on random intercept (hours/day) and linear slopes (hours/day/year) and used as exposure measures in association with MetS at a second step. Trajectories were further dichotomized if children increased their DM duration over time above or below the mean.

Results

10,359 children and adolescents (20,075 total observations, 50.3% females, mean age = 7.9, SD = 2.7) were included. DM exposure increased as children grew older (from 2.2 h/day at 2 years to 4.2 h/day at 16 years). Estonian children showed the steepest DM increase; Spanish children the lowest. The prevalence of MetS at last follow-up was 5.5%. Increasing media use trajectories were positively associated with z-scores of MetS (slope: β = 0.54, 95%CI = 0.20–0.88; intercept: β = 0.07, 95%CI = 0.02–0.13), and its components after adjustment for puberty, diet and other confounders. Children with increasing DM trajectories above mean had a 30% higher risk of developing MetS (slope: OR = 1.30, 95%CI = 1.04–1.62). Boys developed steeper DM use trajectories and higher risk for MetS compared to girls.

Conclusions

Digital media use appears to be a risk factor for the development of MetS in children and adolescents. These results are of utmost importance for pediatricians and the development of health policies to prevent cardio-metabolic disorders later in life.

Trial registration

ISRCTN, ISRCTN62310987. Registered 23 February 2018- retrospectively registered.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12966-021-01186-9.

The Incidence of Adult Obesity is Associated with Parental and Adolescent Histories of Obesity in North Sumatra, Indonesia: A Cross-Sectional Study

Purpose

Obesity that occurs in adulthood is influenced by various factors, not only energy balance, especially concerning the amount of energy consumed, but also heredity. The hereditary factors of obese parents on childhood obesity have been studied, but what about adulthood? This study examines the relationship between a history of obesity in adolescence, and maternal and paternal incidences of adult obesity.

Patients and Methods

This study was a cross-sectional study that included adult men and women aged 20–60 years old. The subjects had no chronic or metabolic disease. This research was conducted from April to November, 2020, in North Sumatra Province, Indonesia. The parameters studied were demographics, daily food intake, anthropometry and a history of obesity in adolescence, and for the participants’ fathers and mothers. The statistical test used was the chi-squared test/Fisher test.

Results

This study included 136 research subjects, 60 male and 76 female; based on the results of the study, 47.8% were found to be obese, but food intake showed a low intake (96.2%). There was a significant relationship between a history of obesity in adolescence and incidences of obesity (≥30 kg/m²) in the mother and father, with significance values of p=0.01, p=0.004, and p=0.001, respectively.

Conclusion

This study found that there was a significant relationship between a history of obesity in adolescence and incidences of adult obesity (≥ 30kg/m²) in parents, but not with the level of food intake per day. The risk of obesity will increase further with a history of obesity in parents and obesity in adolescence, and this can be used to understand and prevent obesity.

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Breaks in Sedentary Time and Cardiometabolic Markers in Adolescents

BACKGROUND

The interruption of the time spent in sedentary behavior (breaks) has been associated with better levels of cardiometabolic indicators in the adult population, but in adolescents, further investigations are still needed to confirm these findings.

OBJECTIVES

To analyze the association of the number of breaks per day in sedentary behaviors with cardiometabolic markers and whether it was moderated by nutritional status and excessive time on sedentary behavior in adolescents.

METHODS

This is a cross-sectional study of 537 adolescents (52.3% girls), aged between 10 and 14 years, enrolled in public schools in the city of João Pessoa, Paraíba state, Brazil. The number of daily breaks (>100 counts/minutes) in sedentary time was measured by Actigraph GT3X+ accelerometers. The following cardiometabolic markers were analyzed: systolic and diastolic blood pressure (mmHg), fasting blood glucose levels, total cholesterol, triglycerides, HDL-c, LDL-c (all in mg/dL) and body mass index (BMI) (kg/m2). Linear regression was used to analyze the association between the number of breaks and cardiometabolic markers and whether this association was moderated by nutritional status and excessive time in sedentary behavior. The significance level of p<0.05 was adopted for all analyses.

RESULTS

The number of daily breaks was negatively associated with BMI (boys - ß = -0.083; 95%CI: -0.132; -0.034 and girls - ß = -0.115; 95%CI: -0.169; -0.061), but not with the remaining cardiometabolic markers. The number of breaks per day was negatively associated with BMI (ß = -0.069; 95% CI: -0.102; -0.035), but not with the other cardiometabolic markers and this association was not moderated by the adolescents' nutritional status (p=0.221), or by excessive time in sedentary behavior (p=0.176).

CONCLUSIONS

Including breaks in sedentary time seems to contribute to lower BMI values in adolescents.

Association of sedentary patterns with body fat distribution among US children and adolescents: a population-based study

BACKGROUND/OBJECTIVES

Children and adolescents spend a substantial amount of time being sedentary. The impact of prolonged sedentary patterns on fat distribution has not been elucidated especially in the context of physical activity level. Our objective is to examine the independent and joint associations of prolonged sedentary patterns and physical activity level with fat distribution among children and adolescents.

SUBJECTS/METHODS

This included US children (8-11 years) and adolescents (12-19 years) from the National Health and Nutrition Examination Survey 2003-2006. Sedentary patterns comprise accelerometer-measured average sedentary bout duration and self-reported time of sitting watching TV/videos. Fat distribution (trunk and total fat percentage) was determined via dual X-ray absorptiometry.

RESULTS

Among 810 children and 2062 adolescents, average sedentary bout duration was associated with greater total and trunk fat percentages only among male children, after adjusting for moderate-to-vigorous physical activity (MVPA) level by accelerometer. Prolonged sitting watching TV/videos was associated with higher total and trunk fat percentages in male children and all adolescents, independent of levels of MVPA (all P for trend <0.05). Compared with ≤1 h/day, male children who spent ≥4 h/day sitting watching TV/videos had 4.43% higher trunk fat (95% CI, 1.69-7.17%), with similar associations for female (3.53%; 95% CI, 1.03-6.03%) and male adolescents (4.78%; 95% CI, 2.97-6.60%). About 13-17% children and adolescents spent <1 h on MVPA and ≥4 h sitting watching TV/videos per day. Compared with the most active group (MVPA ≥ 1 h/day and sitting watching TV/videos ≤1 h/day), trunk fat in this least active group was 6.21% higher in female children, 9.90% higher in male children, 6.84% higher in female adolescents, and 5.36% higher in male adolescents.

CONCLUSIONS

Prolonged time spent on sitting watching TV/videos was associated with fat accumulation among children and adolescents, independent of physical activity level.

Longitudinal differences in levels and bouts of sedentary time by different day types among Australian toddlers and pre-schoolers

The aim of the present study was to characterize sedentary time (ST) and sedentary bouts among young children, across a typical week and by day type (childcare days, non-childcare days and weekends), over a 12-month period.ST % (ST/accelerometer wear time*100) and number of sedentary bouts/hours were assessed using accelerometers at two time-points 12-months apart in 153 toddlers and 74 pre-schoolers. Differences between baseline and follow-up according to the whole week and the different day types were calculated using linear mixed models with adjustment for age, sex, socio-economic status and zBMI.During the weekend, toddlers had more 20-30 min/h sedentary bouts at follow-up than at baseline (MD: 0.03). In pre-schoolers, ST % (MD:-8.4), the number of 1-4 min/h (MD:-1.45), 5-9 min/h (MD: -0.46) and 10-19 min/h sedentary bouts (MD:-0.11) were lower at baseline, compared to follow-up, on non-childcare days; as were the number of 5-9 min/h sedentary bouts on weekends (MD:0.40). P < 0.05 for all.This study found that longer sedentary bouts (20-30 min/h) tended to decrease among toddlers and pre-schoolers, whereas ST and shorter sedentary bouts increased over 12-months, particularly among pre-schoolers on non-childcare weekdays. Non-childcare days, and home environment may be targeted for intervention to reduce ST and sedentary bouts among pre-schoolers.

Sedentary activity bout length was associated with BMI and waist circumference in Swedish children aged 5-7 years

AIM

This study examined the pattern of sedentary behaviour during the week and on weekends and associations with health outcomes among children aged 5-7 years in Sweden.

METHODS

This cross-sectional study used data from 342 children, many of whom had at least one parent born outside the Nordic region. Physical activity and sedentary time were measured by accelerometry. A sedentary bout was defined as 1-4 and 5-9 min. Diet, time in front of television or computer screen, sleep and physical activity behaviour were measured via parental reports, and anthropometric data by research staff.

RESULTS

The number of sedentary bouts was higher on weekends than on weekdays. Compared to girls, boys had more 1-4 min bouts on both weekdays and weekend days, and more 5-9 min bouts on weekends. A higher number of 5-9 min bouts was associated with a higher body mass index and waist circumference.

CONCLUSION

This study showed an association between sedentary activity and weight status in children as young as 5-7 years. Reducing time, especially longer bouts, spent in sedentary activities may encourage healthy weight development in children.

Comparison of Classroom-Based Sedentary Time and Physical Activity in Conventional Classrooms and Open Learning Spaces Among Elementary School Students

European children and adolescents spend most of their daily life and especially their school hours being sedentary which may increase their risk for chronic non-communicable diseases later in life. After the curriculum reform of Finnish basic education in 2014, most of the new or renovated comprehensive schools in Finland incorporate open and flexible classroom designs. Their open learning spaces may provide students opportunities to reduce sedentary behavior during school hours. Thus, waist-worn accelerometers were used to assess classroom-based sedentary time (ST), the number of breaks from sedentary time (BST), and physical activity (PA) among cross-sectional samples of 3rd and 5th grade students during two separate academic years in a school that underwent a renovation from conventional classrooms to open learning spaces. The cohort of 5th grade students before renovation had a smaller proportion of ST from total classroom time (56.97 ± 12.24%, n = 42 vs. 67.68 ± 5.61%, n = 28, mean difference = 10.71%-points, 95%CI = −15.65 to−5.77, p < 0.001), a greater number of BST per 60 min of classroom time (7.41 ± 1.16 breaks/h vs. 9.19 ± 1.59 breaks/h, mean difference = −1.78 breaks/h, 95%CI = −2.486 to −1.079, p < 0.001) and a greater proportion of light intensity PA (28.66 ± 9.99% vs. 22.56 ± 4.59%, mean difference = 6.10%, 95%CI = 2.56 to 9.64, p = 0.001) than the 5th grade cohort assessed after renovation. The cohort of 3rd grade student had a greater proportion of moderate-to-vigorous intensity PA (MVPA) after the renovation compared to the cohort assessed before the renovation [Mean Rank (Before) = 27.22, Mean Rank (After) = 37.58, U =524.0, p = 0.033]. Despite the greater ST found in 5th graders, schools with open learning spaces may facilitate BST or MVPA as observed in the 5th and 3rd grade cohorts in open learning spaces compared to the cohorts in conventional classrooms, respectively. Future studies should seek to investigate and develop teacher practices to capitalize the potential of open classrooms to reduce ST, since classroom renovation alone may not be a sufficient intervention as of itself. Longitudinal studies utilizing randomized controlled trials are warranted.

Relationship of Physical Activity and Sedentary Time with Metabolic Health in Children and Adolescents Measured by Accelerometer: A Narrative Review

The purpose of this study was to summarize the associations of physical activity (PA) and sedentary time (SED) with metabolic health and examine the effects of time reallocation on metabolic health in adolescents using accelerometer data. A literature search was conducted using PubMed, ScienceDirect, Web of Science, Cochran Library, and Google Scholar, and 27 articles were reviewed. Recent research generally confirms the associations of PA and SED with metabolic health. High PA levels and low SED levels had a positive relationship with metabolic health. Moreover, reallocating 10 min of daily SED to PA was associated with better metabolic health indicators. These results were stronger for moderate-to-vigorous physical activity than for light intensity PA. Thus, efforts to convert SED into PA of at least moderate intensity appear to be an effective strategy to prevent metabolic disease development in children and adolescents. However, some of the associations between PA and metabolic health indicators were inconsistent, depending on age, obesity degree, and PA intensity. Additionally, various accelerometer data collection and processing criteria impact the interpretation of the results. Therefore, consistent accelerometer data collection and analysis methods are needed in future studies. Further, intervention studies are required to verify the causality and effectiveness of the isotemporal substitution model.

Which intensities, types, and patterns of movement behaviors are most strongly associated with cardiometabolic risk factors among children?

PURPOSE

The purpose of this study was to determine which intensities, patterns, and types of 24-h movement behaviors are most strongly associated with cardiometabolic risk factors among children.

METHODS

A total of 369 children aged 10-13 years were studied. Participants wore an Actical accelerometer and a Garmin Forerunner 220 Global Positioning System logger and completed an activity and sleep log for 7 days. Data from these instruments were combined to estimate average minute per day spent in 14 intensities, 11 types, and 14 patterns of movement. Body mass index, resting heart rate, and systolic blood pressure values were combined to create a cardiometabolic risk factor score. Partial least squares regression analysis was used to examine associations between the 39 movement behavior characteristics and the cardiometabolic risk factor score. The variable importance in projection (VIP) values were used to determine and rank important movement behavior characteristics. There was evidence of interaction by biological maturity, and the analyses were conducted separately in the 50% least mature and 50% most mature participants.

RESULTS

For the least biologically mature participants, fifteen of the 39 movement behavior characteristics had important VIP value scores; eight of these reflected movement intensities (particularly moderate and vigorous intensities), six reflected movement patterns, and one reflected a movement type. For the most mature participants, thirteen of the 39 movement behavior characteristics had important VIP value scores, with five reflecting intensities (particularly moderate and vigorous intensities), five reflecting patterns, and three reflecting types of movement.

CONCLUSION

More than 12 movement behavior characteristics were associated with cardiometabolic risk factors within both the most and least mature participants. Movement intensities within the moderate and vigorous intensity ranges were the most consistent correlates of these risk factors.

Effects of a psychosocial intervention at one-year follow-up in a PREDIMED-plus sample with obesity and metabolic syndrome

This study examines if overweight/obesity are related to higher impulsivity, food addiction and depressive symptoms, and if these variables could be modified after 1 year of a multimodal intervention (diet, physical activity, psychosocial support). 342 adults (55-75 years) with overweight/obesity and metabolic syndrome (MetS) from the PREDIMED-Plus Cognition study were randomized to the intervention or to the control group (lifestyle recommendations). Cognitive and psychopathological assessments were performed at baseline and after 1-year follow-up. At baseline, higher impulsivity was linked to higher food addiction and depressive symptoms, but not to body mass index (BMI). Food addiction not only predicted higher BMI and depressive symptoms, but also achieved a mediational role between impulsivity and BMI/depressive symptoms. After 1 year, patients in both groups reported significant decreases in BMI, food addiction and impulsivity. BMI reduction and impulsivity improvements were higher in the intervention group. Higher BMI decrease was achieved in individuals with lower impulsivity. Higher scores in food addiction were also related to greater post-treatment impulsivity. To conclude, overweight/obesity are related to higher impulsivity, food addiction and depressive symptoms in mid/old age individuals with MetS. Our results also highlight the modifiable nature of the studied variables and the interest of promoting multimodal interventions within this population.

Objectively Measured Sedentary Levels and Bouts by Day Type in Australian Young Children

BACKGROUND

This study aimed to understand whether a higher number of sedentary bouts (SED bouts) and higher levels of sedentary time (SED time) occur according to different day types (childcare days, nonchildcare weekdays, and weekends) in Australian toddlers (1-2.99 y) and preschoolers (3-5.99 y).

METHODS

The SED time and bouts were assessed using ActiGraph GT3X+ accelerometers. The sample was composed of 264 toddlers and 343 preschoolers. The SED bouts and time differences were calculated using linear mixed models.

RESULTS

The toddlers' percentage of SED time was higher on nonchildcare days compared with childcare days (mean difference [MD] = 2.3; 95% confidence interval, 0.7 to 3.9). The toddlers had a higher number of 1- to 4-minute SED bouts on nonchildcare days compared with childcare days. The preschoolers presented higher percentages of SED time during nonchildcare days (MD = 3.1; 95% confidence interval, 1.6 to 4.5) and weekends (MD = 1.9; 95% confidence interval, 0.4 to 3.4) compared with childcare days. The preschoolers presented a higher number of SED bouts (1-4, 5-9, 10-19, and 20-30 min) during nonchildcare days and weekends compared with childcare days. No SED times or bout differences were found between nonchildcare days and weekends, neither SED bouts >30 minutes on toddlers nor on preschoolers.

CONCLUSION

The SED time and bouts seem to be lower during childcare periods, which means that interventions to reduce sedentary time should consider targeting nonchildcare days and weekends.

Cardiovascular health indicators in soccer exercise during adolescence: systematic review

This review analyzed the studies that evaluated cardiovascular health indicators (blood pressure, waist circumference, heart rate, glucose index and lipid blood) in recreational soccer players during adolescence, and identify possible associated factors. The search was performed in the electronic databases (PubMED, SciELO, LILACS, Scopus, SPORTDiscus and Web of Science). Inclusion criteria were: population composed of children and/or adolescents (10-19 years or average age up to 19 years); studies adolescents engaged in recreational soccer regularly and observational studies with cross-sectional or longitudinal design. The process of analysis of studies involved reading titles, abstracts and full texts. After these phases, seven articles were eligible. Regarding the design, all studies were cross-sectional. Of the total studies included, five presented moderate methodological quality values and two presented low methodological quality values, according to National Heart, Lung, and Blood Institute instrument. The most cardiovascular health indicators used in recreational soccer players during adolescence was waist circumference; three studies analyzed heart rate, two evaluated blood pressure, one analyzed insulin resistance and none of the included studies analyzed lipid profile. Factors associated were analyzed in four studies, being that sedentary time and body mass index (BMI) present association with at least one indicator of cardiovascular health.

Associations of Sedentary Patterns with Cardiometabolic Biomarkers in Physically Active Young Males

PURPOSE

Sitting time (ST) is a serious global health issue and positively associated with cardiometabolic disease. The present study investigated associations between objectively measured ST, sedentary patterns, and cardiometabolic biomarkers in physically active young males.

METHODS

Cross-sectional analysis was completed in 94 males 18-35 yr of age. Total ST, prolonged sedentary bouts (≥30 min with no interruption), and sedentary breaks (transitions from sitting/lying to standing/stepping) were assessed using activPAL. Lipids, insulin, C-peptide, C-reactive protein (CRP), vascular cellular adhesion molecule-1, intercellular adhesion molecule 1, E-selectin, P-selectin, leptin, resistin, and adiponectin were measured using assay kits. The expression of specific proteins related to endothelial dysfunction was determined using quantitative real-time polymerase chain reaction. Associations between total ST, prolonged sedentary bouts, and sedentary breaks with cardiometabolic biomarkers and total ST and levels of gene expression were assessed using generalized linear models.

RESULTS

Total ST was significantly associated with triglycerides (B = 1.814), insulin (B = 2.117), homeostasis model assessment of insulin resistance (B = 0.071), and E-selectin (B = 2.052). Leptin (B = 0.086), E-selectin (B = 1.623), and P-selectin (B = 2.519) were significantly associated with prolonged sedentary bouts, whereas leptin (B = -0.017) and CRP (B = -0.016) were associated with sedentary breaks. After adjustment for moderate to vigorous physical activity, the associations between triglycerides (B = 2.048) and total ST, and between CRP (B = -0.016) and sedentary breaks, remained significant. E-selectin mRNA levels (B = 0.0002) were positively associated with ST with or without adjustment for moderate to vigorous physical activity.

CONCLUSIONS

Total ST and prolonged sedentary bouts were positively associated with several cardiometabolic biomarkers, with interruptions in ST potentially contributing to reduced cardiometabolic risk in physically active young male adults.

Volume and accumulation patterns of physical activity and sedentary time: longitudinal changes and tracking from early to late childhood

BACKGROUND

Physical activity (PA) decreases and sedentary time (SED) increases across childhood, with both behaviours tracking. However, no studies have examined how accumulation patterns of PA and SED (i.e., prolonged bouts, frequency of breaks in sedentary time) change and track over time. The aim of this study was to investigate longitudinal changes in and tracking of total volume and accumulation patterns of SED, light-intensity PA (LPA), moderate-intensity PA (MPA), vigorous-intensity PA (VPA) among boys and girls.

METHODS

In 2008/09 (T1), children in HAPPY (3-5y; n = 758) in Melbourne, Australia wore ActiGraph GT1M accelerometers to objectively assess SED, LPA, MPA and VPA. This was repeated at age 6-8y (T2; n = 473) and 9-11y (T3; n = 478). Ten pattern variables were computed: bouts of ≥ 5-, ≥ 10-, ≥ 15- and ≥ 20-min for SED, ≥ 1- and ≥ 5-min for LPA, ≥ 1-min for MPA, ≥ 1- and ≥ 5-min for VPA, and breaks in SED (interruptions of > 25 counts 15 s^- 1). Longitudinal mixed models examined changes from T1-3, controlling for T1 age. Generalized estimating equations assessed tracking over the three time points, controlling for T1 age and time between measurements. Analyses were stratified by sex.

RESULTS

Total volume and bouts of SED and SED breaks increased, while total volume and bouts of LPA decreased for both sexes. There was a small decrease in total volume of MPA for girls, but time spent in ≥ 1-min bouts increased for both sexes. Total volume of VPA increased for both sexes, with time spent in ≥ 1-min bouts increasing for boys only. All volume and pattern variables tracked moderately for boys, except for all SED bouts ≥ 15-min, LPA bouts ≥ 5-min and MPA bouts ≥ 1-min (which tracked weakly). For girls, total SED and SED bouts ≥ 1-min tracked strongly, total volume of LPA, MPA and VPA, ≥ 5- and ≥ 10-min SED bouts, and ≥ 1-min LPA and MPA bouts tracked moderately, and SED breaks, all SED bouts ≥ 15 min, LPA bouts ≥ 5 min and all VPA bouts tracked weakly.

CONCLUSIONS

Patterns of SED and PA change from early to late childhood; with the exception of SED breaks and VPA, changes were detrimental. Total volumes and short bouts tended to track more strongly than longer bouts. Interventions to prevent declines in PA and increases in SED are important from early in life.

Association of mentally-passive and mentally-active sedentary behaviors with device-measured bouts and breaks of sedentary time in adolescents

Background: Our aim was to analyze the association of self-reported mentally-passive and mentally-active sedentary behaviors with different patterns (bouts and breaks) of device-measured sedentary time in adolescents.

Methods: This was a cross-sectional study conducted among 375 adolescents (177 boys) aged 1015 years. Total time, bouts and breaks of sedentary time were measured through accelerometers. Self-reported sedentary behavior in different activities was summed and divided into mentally-active (playing electronic games, studying and reading) and mentally-passive (watching TV, watching DVD, and using computer for leisure). Bayesian linear regression models were used for association analyses.

Results: Only mentally-passive sedentary behaviors were positively associated with longer bouts [1-4 minutes: mean posterior distribution: -0.431 (95% credible interval: -0.745 to -0.114); =15 minutes: 0.641 (0.122 to 1.222)] and lower number of breaks [-0.138 (-0.228 to -0.044)] of device-measured sedentary time.

Conclusion: Self-reported mentally-passive sedentary behaviors are associated with longer bouts and lower breaks of device-measured sedentary time.

Patterns of Sedentary Time in the Hispanic Community Health Study/Study of Latinos (HCHS/SOL) Youth

BACKGROUND

Total sedentary time and prolonged sedentary patterns can negatively impact health. This study investigated rates of various sedentary pattern variables in Hispanic/Latino youth.

METHODS

Participants were 956 youths (50.9% female) in the Hispanic Community Health Study/Study of Latinos Youth, a population-based cohort study of Hispanic/Latino 8- to 16-year-olds from 4 geographic regions in the United States (2012-2014). Total sedentary time and 10 sedentary pattern variables were measured through 1 week of accelerometer wear. Differences were examined by sociodemographic characteristics, geographic location, weekdays versus weekends, and season.

RESULTS

On average, youth were sedentary during 67.3% of their accelerometer wear time, spent 24.2% engaged in 10- to 29-minute sedentary bouts, and 7.2% in ≥60-minute bouts. 8- to 12-year-olds had more favorable sedentary patterns (less time in extended bouts and more breaks) than 13- to 16-year-olds across all sedentary variables. Sedentary patterns also differed by Hispanic/Latino background, with few differences across sex, household income, season, and place of birth, and none between weekdays versus weekends.

CONCLUSIONS

Variables representing prolonged sedentary time were high among Hispanic/Latino youth. Adolescents in this group appear to be at especially high risk for unhealthy sedentary patterns. Population-based efforts are needed to prevent youth from engaging in increasingly prolonged sedentary patterns.

Patterning of physical activity and sedentary behavior at and away from school in preadolescent children

Background

Understanding how and where children accumulate their physical activity (PA) and sedentary minutes throughout the day has important implications for behavioral interventions.

Purpose

The purpose of this study was to examine the duration and intensity of habitual PA and sedentary time (SED) at and away from school among preadolescent children.

Methods

Data from twenty-one children ages 7-11 (57% girls; 57% non-white; 24% overweight/obese) were included in this analysis. Proportion of time spent in PA, SED, and SED bouts were examined on school days (in-school and out-of-school) and non-school days via accelerometry.

Results

When comparing school time with non-school time on school days, children accumulated a higher proportion of light PA while in-school [49.3% (i.e. 5 minutes 18 seconds) vs. 39.6% (i.e. 3 hours 53 minutes), p=0.01]. While at school, the proportion of time spent in SED was less [46.3% (i.e. 3 hours 7 minutes) vs. 56.3% (i.e. 5 hours 32 minutes), p=0.01] and fewer children spent time engaged in prolonged sitting compared to out-of-school [uninterrupted SED for 30 minutes 52.4% (i.e. 11 children) vs. 85.7% (i.e. 18 children), p=0.02].

Discussion

These findings suggest children are proportionately most active and least sedentary when at school, yet children only accumulated approximately 18 minutes of moderate-to-vigorous PA in this environment.

Translation to Health Education Practice

These preliminary findings can help to inform physical activity programming designed to promote life-long physical activity behaviors in children.

Intervention Effects of the Health Promotion Programme "Join the Healthy Boat" on Objectively Assessed Sedentary Time in Primary School Children in Germany

Sedentary behaviour (SB) in children is related to negative health consequences that can track into adulthood. The programme "Join the Healthy Boat" promotes reduced screen time and a less sedentary lifestyle in schoolchildren. This study investigated the effects of the programme on children's SB. For one year, teachers delivered the programme. A total of 231 children (7.0 ± 0.6 years) participated in the cluster-randomised study; there were 154 one year later at follow-up. Children's SB was assessed using multi-sensor accelerometery, screen time via parental questionnaire. Effects were analysed using (linear) mixed effects regression models. At baseline, children spent 211 (±89) min daily in SB, at follow-up 259 (±109) min/day with no significant difference between the intervention (IG) and control group (CG). SB was higher during weekends (p < 0.01, for CG and IG). However, at follow-up, daily screen time decreased in IG (screen time of >1 h/day: baseline: 33.3% vs. 27.4%; follow-up: 41.2% vs. 27.5%, for CG and IG, respectively). This multi-dimensional, low-threshold intervention for one year does not seem to achieve a significant reduction in children's SB, although screen time decreased in IG. Therefore, it should be considered that screen time cannot be the key contributor to SB and should not solely be used for changing children's SB. However, if screen time is targeted, interventions should promote the replacement of screen time with active alternatives.

Longitudinal Changes in Children's Accelerometer-derived Activity Pattern Metrics

PURPOSE

The objective of this study was to quantify age-related changes in accelerometer-derived day-level physical activity and sedentary behavior pattern metrics (i.e., number, length, and temporal dispersion of bouts and breaks) across 3 yr of middle childhood. Differences by child sex and weekend versus weekday were examined.

METHOD

Children (N = 169, 54% female, 56% Hispanic; 8-12 yr old at enrollment) participated in a longitudinal study with six assessments across 3 yr. Day-level moderate-to-vigorous physical activity (MVPA; i.e., total minutes, number of short (<10 min) bouts, proportion of long (≥20 min) bouts, temporal dispersion) and sedentary behavior (i.e., total minutes, number of breaks, proportion of long (≥60 min) bouts, temporal dispersion) pattern metrics were measured using a waist-worn accelerometer (Actigraph GT3X).

RESULTS

Random intercept multilevel linear regression models showed that age-related decreases in the number of short MVPA bouts per were steeper for girls than for boys (b = -1.28; 95% confidence interval (CI), -1.93 to -0.64; P < 0.01) and on weekend days than on weekdays (b = -1.82; 95% CI, -2.36 to -1.29; P < 0.01). The evenness of the temporal dispersion of MVPA across the day increased more on weekend days than on weekdays as children got older (b = -0.02; 95% CI, -0.02 to -0.01; P < 0.01). Girls had steeper age-related decreases in the number of sedentary breaks per day (b = -2.89; 95% CI, -3.97 to -1.73; P < 0.01) and the evenness of the temporal dispersion of sedentary behavior across the day (b ≤ 0.01; 95% CI, <0.01 to 0.01; P < 0.01) than did boys. Changes in sedentary behavior metrics did not differ between weekend days and weekdays.

CONCLUSION

Strategies to protect against declines in short physical activity bouts and promote sedentary breaks, especially among girls and on weekend days, could reduce cardiometabolic risks.

Fitness, physical activity, or sedentary patterns? Integrated analysis with obesity surrogates in a large youth sample

OBJECTIVE

Physical fitness (PF) and physical activity (PA) are inversely associated with body mass index and waist circumference (WC), whereas sedentary time (ST) seems to boost obesity in youth. The aim was to examine the associations of each selected PF test, PA-related exposures, and specific ST patterns with obesity and determine the most relevant ones, in a large sample of a school-aged adolescent.

METHODS

The sample consisted of 2696 Portuguese youth aged 10 to 18 years. Height, weight, and WC were measured. PA and ST components were measured using accelerometry. PF was evaluated using a battery of tests.

RESULTS

The Progressive Aerobic Cardiovascular Endurance Run (PACER) and push-up tests seemed to be the exposures that presented the strongest and more consistent associations with obesity, independent of PA/ST profiles (P < .05). The second exposure of relevance for adolescent obesity level was the breaks in ST with a negative relationship regardless of PA/PF profiles (P < .05). Finally, ST accumulated in periods of <30 minutes, and moderate-to-vigorous PA were favorably associated with obesity, independent of ST/PF.

CONCLUSIONS

Independent of PA and ST, cardiorespiratory fitness (CRF), measured by PACER, was associated with obesity markers. This may be in part due to the dependence of PACER performance on adiposity. Also, limiting prolonged ST and promoting interruptions in this behavior were associated with obesity. These associations suggest that future research should examine other strategies beyond PA promotion for tackling obesity that consider CRF and breaking ST.

Objectively measured sedentary behaviour in overweight and obese prepubertal children: challenging the school

Sedentary lifestyle is associated with unfavourable health outcomes; however, few studies have analysed the daily fluctuations of sedentary behaviour in children. The aim was to characterise sedentary behaviour in low active, overweight/obese prepubertal children and to examine whether there were daily, age- or gender-based differences. In this observational study free-living movement was measured by accelerometry for one week. Eighty-eight low active, overweight/obese children (8- to 12-year-olds) were included. Analysis was conducted for weekends, weekdays, school time and non-school time on weekdays. Participants spent half of their waking hours engaged in sedentary behaviour (48.1%). Short sedentary bouts (1-4 min) accounted for 86% of sedentary time. Sedentary time was similar on weekends and non-school time, while it was highest during school time. Interventions for the management of childhood obesity should include strategies for shifting sedentary time to physical activity on weekends and non-school time and implementing more activity-permissive classroom lessons.

Differences in adolescent activity and dietary behaviors across home, school, and other locations warrant location-specific intervention approaches

BACKGROUND

Investigation of physical activity and dietary behaviors across locations can inform "setting-specific" health behavior interventions and improve understanding of contextual vulnerabilities to poor health. This study examined how physical activity, sedentary time, and dietary behaviors differed across home, school, and other locations in young adolescents.

METHODS

Participants were adolescents aged 12-16 years from the Baltimore-Washington, DC and the Seattle areas from a larger cross-sectional study. Participants (n = 472) wore an accelerometer and Global Positioning Systems (GPS) tracker (Mean days = 5.12, SD = 1.62) to collect location-based physical activity and sedentary data. Participants (n = 789) completed 24-h dietary recalls to assess dietary behaviors and eating locations. Spatial analyses were performed to classify daily physical activity, sedentary time patterns, and dietary behaviors by location, categorized as home, school, and "other" locations.

RESULTS

Adolescents were least physically active at home (2.5 min/hour of wear time) and school (2.9 min/hour of wear time) compared to "other" locations (5.9 min/hour of wear time). Participants spent a slightly greater proportion of wear time in sedentary time when at school (41 min/hour of wear time) than at home (39 min/hour of wear time), and time in bouts lasting ≥30 min (10 min/hour of wear time) and mean sedentary bout duration (5 min) were highest at school. About 61% of daily energy intake occurred at home, 25% at school, and 14% at "other" locations. Proportionately to energy intake, daily added sugar intake (5 g/100 kcal), fruits and vegetables (0.16 servings/100 kcal), high calorie beverages (0.09 beverages/100 kcal), whole grains (0.04 servings/100 kcal), grams of fiber (0.65 g/100 kcal), and calories of fat (33 kcal/100 kcal) and saturated fat (12 kcal/100 kcal) consumed were nutritionally least favorable at "other" locations. Daily sweet and savory snacks consumed was highest at school (0.14 snacks/100 kcal).

CONCLUSIONS

Adolescents' health behaviors differed based on the location/environment they were in. Although dietary behaviors were generally more favorable in the home and school locations, physical activity was generally low and sedentary time was higher in these locations. Health behavior interventions that address the multiple locations in which adolescents spend time and use location-specific behavior change strategies should be explored to optimize health behaviors in each location.

Feasibility and applicability of Evenson sedentary behavior cut points applied to children with and without intellectual and developmental disabilities

AIM

Sedentary behavior (SB) is widely studied as it is associated with cardiometabolic health and obesity issues. However, children with Intellectual and Developmental Disabilities (IDD) have been understudied. Accelerometers are commonly used to measure SB in typically developing populations but may be inappropriate for IDD populations due to differences in body movement and physiologic responses to the activity. The use of Evenson sedentary cut-points, created based on typically developing children, has yet to be applied and/or examined in children with IDD.

PURPOSE

A descriptive cross-sectional study was conducted to (1) Assess the feasibility of applying Evenson sedentary cut-points in children with IDD (2) Describe SB over a two-week period between diagnosis groups.

METHODS

The SB of 22 participants (8 children with Down syndrome, 6 children with spina bifida, 8 children with no chronic illness) was assessed on two separate occasions: (1) during a 7-minute sedentary protocol, and (2) over a two-week period.

RESULTS

The study supports the preliminary efficacy of using Evenson cut-points for this population, with 100% of participants being within the Evenson counts per minute (0-100 cpm) during the 7-minute sedentary protocol. The total volume of SB over a two-week period was not significantly different between diagnosis groups (8.8 h, 8.6 h, and 7.1 h of SB for children with Down syndrome, spina bifida, or those with no chronic illness, respectively; p = 0.36).

CONCLUSIONS

Evenson sedentary cut-points can be used for children with IDD. Preliminary data suggest that children with IDD do not engage in significantly different SB than children without a chronic illness. Further study is warranted.Implications for rehabilitationObjective measures of physical activity and sedentary behavior for children with Down syndrome or spina bifida are rarely used due to potential differences in body movement (e.g., gait) during ambulation compared to typically developing peers that may influence the accuracy of cut-points.This study supports that Evenson sedentary cut-points can be used in children with Down syndrome or spina bifida to assess sedentary activity.Preliminary findings from this study demonstrate similarities in patterns of sedentary behaviors exhibited by our sample of children with Down syndrome, spina bifida, or no chronic illness.

How do short sleepers use extra waking hours? A compositional analysis of 24-h time-use patterns among children and adolescents

BACKGROUND

To examine compositional associations between short sleep duration and sedentary behavior (SB), light physical activity (LPA) and moderate-to-vigorous physical activity (MVPA) among children and adolescents.

METHODS

Multi-day 24-h data on sleep, SB, LPA and MVPA were collected using accelerometers among 343 children (8-13 years old) and 316 adolescents (14-18 years old). Children and adolescents with sleep duration of < 9 and < 8 h, respectively, were classified as short sleepers. Robust compositional regression analysis was used to examine the associations between short sleep duration and the waking-time composition.

RESULTS

Seventy-one percent of children and 75.3% of adolescents were classified as short sleepers. In children, being a short sleeper was associated with higher SB by 95 min/day (p < 0.001) and lower MVPA by 16 min/day (p = 0.002). Specifically, it was associated with a higher amount of time spent in long sedentary bouts (β_ilr1 = 0.46, 95% confidence interval [CI] = 0.29 to 0.62) and lower amounts of time spent in sporadic SB (β_ilr1 = - 0.17, 95% CI = -0.24 to - 0.10), sporadic LPA (β_ilr1 = - 0.09, 95% CI = -0.14 to - 0.04) and sporadic MVPA (β_ilr1 = - 0.17, 95% CI = -0.25 to - 0.10, p < 0.001 for all), relative to the remaining behaviours. In adolescents, being a short sleeper was associated with a higher amount of time spent in SB by 67 min/day (p = 0.001) and lower LPA by 2 min/day (p = 0.035). Specifically, it was associated with more time spent in sedentary bouts of 1-9 min (β_ilr1 = 0.08, 95% CI = 0.02 to 0.14, p = 0.007) and 10-29 min (β_ilr1 = 0.10, 95% CI = 0.02 to 0.18, p = 0.015), relative to the remaining behaviours.

CONCLUSIONS

Among children and adolescents, short sleep duration seems to be highly prevalent and associated with less healthy waking time. Public health interventions and strategies to tackle the high prevalence of short sleep duration among children and adolescents are warranted.

School- and Leisure Time Factors Are Associated With Sitting Time of German and Irish Children and Adolescents During School: Results of a DEDIPAC Feasibility Study

Objective: The study aims to investigate to what extent school- and leisure time-related factors are associated with sedentary behavior during school in German and Irish children and adolescents. Methods: The study based on a sample of 198 children and adolescents surveyed in 2015. Sedentary and activity behavior were measured using the activPAL physical activity monitor. Information on socio-economic status, school- and leisure-time related factors were provided by questionnaires. Associations between school- and leisure time-related factors and sedentary time during school were estimated using linear multi-level models. Results: Access to play equipment in school was associated with reduced sitting time (hours/day) of children (ß = 0.78; 95%CI = 0.06-1.48). Media devices in bedroom and assessing the neighborhood as activity friendly was associated with increased sitting time of children (ß = 0.92; 95%CI = 0.12-1.72 and ß = 0.30; 95%CI = 0.01-0.60, respectively). The permission to use media devices during breaks was associated with increased sitting time (hours/day) of adolescents (ß = 0.37; 95% CI = 0.06-0.69). A less safe traffic surrounding at school was associated with reduced sitting time of adolescents (ß = -0.42; 95% CI = -0.80 to -0.03). Conclusion: Results suggest that school- and leisure time-related factors are associated to the sedentary behavior during school. We suggest that future strategies to reduce sedentary time should consider both contexts.

Sedentariness and Physical Activity during School Recess Are Associated with VO2Peak

Recess time (RT) is a main component of school-based activities, and could contribute up to 40% of the physical activity (PA) recommended in the health guidelines. The main goal was to analyze the association between accelerometer-measured PA and sedentary time during RT with cardiorespiratory fitness (CRF). A total of 146 children and adolescents, aged 8-19 years, were recruited from six schools. PA levels were measured with GT3X accelerometers over 7 days. CRF was measured using a portable breath-by-breath gas analyzer. A general linear model (GML) was conducted to analyze the association between PA intensities and CRF during RT. Additionally, a logistic binary regression was used to evaluate the risk of unhealthy CRF among different categories of PA and sedentary time. Participants classified as healthy showed higher PA levels during RT than those classed as unhealthy. GML analysis showed that sedentary time during RT was significantly associated with VO2Peak. Finally, individuals who were sedentary for more than 15 min during RT presented 97.7% lower odds of having unhealthy CRF (adjusted Odds Ratio = 0.023, 95% CI -0.002 to 0.263). Our data suggest an association between recess sedentary time and unhealthy CRF. Thus, school-aged children and adolescents must be empowered to perform PA during RT to prevent the deleterious effects of sedentary time on CRF.

Tracking of total sedentary time and sedentary patterns in youth: a pooled analysis using the International Children's Accelerometry Database (ICAD)

Background

To gain more understanding of the potential health effects of sedentary time, knowledge is required about the accumulation and longitudinal development of young people’s sedentary time. This study examined tracking of young peoples’ total and prolonged sedentary time as well as their day-to-day variation using the International Children’s Accelerometry Database.

Methods

Longitudinal accelerometer data of 5991 children (aged 4-17y) was used from eight studies in five countries. Children were included if they provided valid (≥8 h/day) accelerometer data on ≥4 days, including ≥1 weekend day, at both baseline and follow-up (average follow-up: 2.7y; range 0.7–8.2). Tracking of total and prolonged (i.e. ≥10-min bouts) sedentary time was examined using multilevel modelling to adjust for clustering of observations, with baseline levels of sedentary time as predictor and follow-up levels as outcome. Standardized regression coefficients were interpreted as tracking coefficients (low: < 0.3; moderate: 0.3–0.6; high: > 0.6).

Results

Average total sedentary time at study level ranged from 246 to 387 min/day at baseline and increased annually by 21.4 min/day (95% confidence interval [19.6–23.0]) on average. This increase consisted almost entirely of prolonged sedentary time (20.9 min/day [19.2–22.7]). Total (standardized regression coefficient (B) = 0.48 [0.45–0.50]) and prolonged sedentary time (B = 0.43 [0.41–0.45]) tracked moderately. Tracking of day-to-day variation in total (B = 0.04 [0.02–0.07]) and prolonged (B = 0.07 [0.04–0.09]) sedentary time was low.

Conclusion

Young people with high levels of sedentary time are likely to remain among the people with highest sedentary time as they grow older. Day-to-day variation in total and prolonged sedentary time, however, was rather variable over time.

The association between screen time and cardiometabolic risk in young children

OBJECTIVES

While studies exist on the association between screen time and cardiometabolic risk among adolescents, research examining the effect of screen time on cardiometabolic risk in young children is lacking. The primary objective of this study was to examine the association between daily screen time and cardiometabolic risk (CMR) [sum of age- and sex-standardized z-scores of systolic blood pressure (SBP), glucose, log-triglycerides, waist circumference (WC), and negative high-density lipoprotein (HDL) cholesterol divided by the square root of five] in young children. Secondary objectives included examining individual CMR risk factors, including waist-to-height ratio and non high-density lipoprotein (non-HDL) cholesterol, as well as the individual cut-offs of these risk factors. Additional analyses include examining the association between screen time and CMR by handheld/non-handheld devices.

METHODS

A study was conducted among young children 3 to 6 years from the TARGet Kids! practice-based research network in Toronto and Montreal, Canada. Children with one or more measures of screen time and CMR were included in this study. Generalized estimating equation (GEE) multivariable linear regressions and multivariable logistic regressions, using published cut-offs, were conducted to evaluate these associations.

RESULTS

Data from 1317 children [mean age 52 months (SD = 13.36), 44.34% female] were included for analyses. There was no evidence of associations between screen time and total CMR score or individual risk factors (p > 0.05) after adjusting for confounders. A statistically significant, but small association between daily screen time and non-HDL cholesterol was found (B = 0.046; CI = [0.017 to 0.075]; p = 0.002.

CONCLUSIONS

Though no relationship was reported between daily screen time and the majority of CMR factors in early childhood, there was an association between daily screen time and non-HDL cholesterol. As the relationship between daily screen time and CMR factors may not be apparent in early childhood, studies to evaluate longer-term cardiometabolic effects of screen time are needed. Although there is an evidence-based rationale to reduce screen time in early childhood, prevention of cardiometabolic risk may not be the primary driver.

Sedentary behavior patterns and adiposity in children: a study based on compositional data analysis

BACKGROUND

Between-person differences in sedentary patterns should be considered to understand the role of sedentary behavior (SB) in the development of childhood obesity. This study took a novel approach based on compositional data analysis to examine associations between SB patterns and adiposity and investigate differences in adiposity associated with time reallocation between time spent in sedentary bouts of different duration and physical activity.

METHODS

An analysis of cross-sectional data was performed in 425 children aged 7-12 years (58% girls). Waking behaviors were assessed using ActiGraph GT3X accelerometer for seven consecutive days. Multi-frequency bioimpedance measurement was used to determine adiposity. Compositional regression models with robust estimators were used to analyze associations between sedentary patterns and adiposity markers. To examine differences in adiposity associated with time reallocation, we used the compositional isotemporal substitution model.

RESULTS

Significantly higher fat mass percentage (FM%; β_ilr1 = 0.18; 95% CI: 0.01, 0.34; p = 0.040) and visceral adipose tissue (VAT; β_ilr1 = 0.37; 95% CI: 0.03, 0.71; p = 0.034) were associated with time spent in middle sedentary bouts in duration of 10-29 min (relative to remaining behaviors). No significant associations were found for short (< 10 min) and long sedentary bouts (≥30 min). Substituting the time spent in total SB with moderate-to-vigorous physical activity (MVPA) was associated with a decrease in VAT. Substituting 1 h/week of the time spent in middle sedentary bouts with MVPA was associated with 2.9% (95% CI: 1.2, 4.6), 3.4% (95% CI: 1.2, 5.5), and 6.1% (95% CI: 2.9, 9.2) lower FM%, fat mass index, and VAT, respectively. Moreover, substituting 2 h/week of time spent in middle sedentary bouts with short sedentary bouts was associated with 3.5% (95% CI: 0.02, 6.9) lower FM%.

CONCLUSIONS

Our findings suggest that adiposity status could be improved by increasing MVPA at the expense of time spent in middle sedentary bouts. Some benefits to adiposity may also be expected from replacing middle sedentary bouts with short sedentary bouts, that is, by taking standing or activity breaks more often. These findings may help design more effective interventions to prevent and control childhood obesity.

Tune out and turn in: the influence of television viewing and sleep on lipid profiles in children

BACKGROUND/OBJECTIVES

Physical activity is beneficial to lipid profiles; however, the association between sedentary behavior and sleep and pediatric dyslipidemia remains unclear. We aimed to investigate whether sedentary behavior or sleep predicted lipid profiles in children over a 2-year period.

SUBJECTS/METHODS

Six hundered and thirty children from the QUALITY cohort, with at least one obese parent, were assessed prospectively at ages 8-10 and 10-12 years. Measures of sedentary behavior included self-reported TV viewing and computer/video game use. Seven-day accelerometry was used to derive sedentary behavior and sleep duration. Adiposity was assessed using DEXA scans. Twenty-four-hour dietary recalls yielded estimates of carbohydrate and fat intake. Outcomes included fasting total cholesterol, triglycerides, HDL and LDL-cholesterol. Multivariable models were adjusted for adiposity and diet.

RESULTS

At both Visit 1 (median age 9.6 year) and Visit 2 (median age 11.6 year), children were of normal weight (55%), overweight (22%), or obese (22%). Every additional hour of TV viewing at Visit 1 was associated with a 7.0% triglyceride increase (95% CI: 3.5, 10.6; P < 0.01) and 2.6% HDL decrease (95% CI: -4.2, -0.9; P < 0.01) at Visit 2; findings remained significant after adjusting for adiposity and diet. Every additional hour of sleep at Visit 1 predicted a 4.8% LDL decrease (95% CI: -9.0, -0.5; P = 0.03) at Visit 2, after adjusting for fat intake; this association became nonsignificant once controlling for adiposity.

CONCLUSIONS

Longer screen time during childhood appears to deteriorate lipid profiles in early adolescence, even after accounting for other major lifestyle habits. There is preliminary evidence of a deleterious effect of shorter sleep duration, which should be considered in further studies.

Sedentary behaviour in hospitalised older people: a scoping review protocol

BACKGROUND

Older adults spend up to 23 h daily sitting or lying while in hospital. Sedentary behaviour (SB) within a hospital setting is often associated with poor health outcomes including physical and cognitive decline, reduced quality of life and death as well as hospital readmissions. Conversely, replacing SB with mild to moderate levels of physical activity such as walking can significantly reduce hospital readmission risk by 30 days. Given the potentially harmful effects of SB in hospitalised older adults, it is vital to identify current literature by broadly exploring different aspects of SB among older people in hospital. The overall aim of this scoping review is to produce a literature map of current evidence on key domains of sedentary behaviour in hospitalised older people.

METHOD

A search for relevant publications will be undertaken in Pedro, MEDLINE Ovid, Cochrane, Scopus, Cumulative Index to Nursing and Allied Health Literature, PsychInfo, Embase, Ageline, Joanna Briggs Institute (JBI) and clinical trials registries. Publications in English and those where the author can provide the full text in English will be included. Studies conducted in hospitals (including in-patient rehabilitation facilities) or acute and subacute care settings and in people aged ≥ 65 will be included. A three-stage method will be used to identify relevant articles, consisting of database search using keywords, keywords and index words across all databases, and reference searching. Articles will be selected following screening of titles/abstracts succeeded by a full-text appraisal utilising a standardised selection form. Two independent reviewers will extract data using the standardised form that will be tested on two articles. A narrative summary will accompany results presented in tables and figures.

Reciprocal associations between depression and screen-based sedentary behaviors in adolescents differ by depressive symptom dimension and screen-type

BACKGROUND

The heterogeneity of depression and sedentary behavior complicates understanding of mechanisms underlying and interventions addressing comorbid depression and sedentary behavior in adolescents. This study investigated reciprocal associations between four depressive symptom dimensions and two types of screen-based sedentary behaviors in adolescents, and tested whether these associations differed by sex.

METHODS

A school-based longitudinal cohort (N = =2,717, baseline Mage=14.57 years) completed questionnaires during two assessments one year apart. Participants reported on levels of four depressive symptom dimensions (continuous) and television viewing and computer/videogame use (≥2 h/day; yes vs. no).

RESULTS

Reciprocal associations between computer/videogame use and higher negative affect symptoms were observed (computer/video games predicting negative affect, β=0.06, 95%CI 0.01-0.11, p = =0.01; negative affect predicting computer/video games, OR 1.29, 95%CI 1.06-1.58, p = =0.01). The relationship between baseline computer/videogame use and subsequent negative affect differed by sex (p = =0.02), and was significant in girls (β=0.11, 95%CI 0.04-0.18, p = =0.002), but not boys (β=0.004, 95%CI -0.06-0.07, p = =0.90). Baseline computer/videogame use predicted somatic symptoms at follow-up (β=0.06, 95%CI 0.01-0.10, p = =0.02), but the reverse association was non-significant. Higher baseline positive affect predicted computer/videogame use at follow-up (OR 1.16, 95%CI 1.02-1.31, p = =0.02), but the reverse association was non-significant. Television viewing was unrelated to each depressive symptom dimension in either direction.

LIMITATIONS

Self-reports may be subject to recall errors and biases, and do not provide clinical diagnoses.

CONCLUSIONS

Associations are not uniform across screen-based sedentary behavior type, depressive symptom dimension, and sex. The association between computer/videogame use and negative affect symptoms may be reciprocal across time and particularly robust among girls.

Associations between accelerometry measured physical activity and sedentary time and the metabolic syndrome: A meta-analysis of more than 6000 children and adolescents

BACKGROUND

Metabolic syndrome is increasingly prevalent in the pediatric population. To prevent an early onset, knowledge about its association with modifiable lifestyle factors is needed.

OBJECTIVES

To estimate the prevalence of the metabolic syndrome and examine its cross-sectional associations with physical activity and sedentary time.

METHODS

Participants were 6009 children and adolescents from 8 studies of the International Children's Accelerometry Database. Physical activity and sedentary time were measured by accelerometer. Metabolic syndrome was defined based on International Diabetes Federation criteria. Logistic regression models adjusted for sex, age and monitor wear time were used to examine the associations between physical activity, sedentary time and the metabolic syndrome in each study and effect estimates were combined using random-effects meta-analysis.

RESULTS

The overall prevalence of the metabolic syndrome was 2.9%. In crude models, a 10 min increase in moderate-to-vigorous intensity physical activity and vigorous-intensity physical activity were inversely associated with the metabolic syndrome [OR 0.88, 95% CI 0.82-0.94, OR 0.80, 95% CI 0.70-0.92]. One hour increase in sedentary time was positively associated with the metabolic syndrome [OR 1.28, 95% CI 1.13-1.45]. After adjustment for sedentary time, the association between moderate-to-vigorous-intensity physical activity and the metabolic syndrome remained significant [OR 0.91, 95% CI 0.84-0.99]. Sedentary time was not associated with the metabolic syndrome after adjustment for moderate-to-vigorous intensity physical activity [OR 1.14 95% CI 0.96-1.36].

CONCLUSIONS

Physical activity of at least moderate intensity but not sedentary time is independently associated with the metabolic syndrome.

Accelerometer-Measured Physical Activity and Sedentary Behavior Patterns in Taiwanese Adolescents

Levels of physical activity and sedentary behavior among adolescents seem to vary within different settings, but few Asian studies have compared physical activity and sedentary activity patterns in adolescents across weekdays/weekends and during-school time/after-school time. This study aimed to provide objectively measured data describing intensity-specific physical activity and sedentary behavior patterns in Taiwanese adolescents. The results were sorted by gender and divided between weekdays/weekends and during-school time/after-school time. A total of 470 Taiwanese students (49.6% boys, ages 12–15 y) were recruited and fitted with GT3X+ accelerometers for seven days. Intensity-specific physical activity, total sedentary time, and sedentary bouts (number and duration ≥30 min) were measured. The Mann-Whitney U test was used to examine the significant differences in physical activity and sedentary behavior patterns between the genders on weekdays/weekends and during school/after-school time. The results show that the adolescents’ overall activity levels were below recommended thresholds, with girls engaging in significantly less moderate to vigorous physical activity, having longer sedentary time, longer time spent in sedentary bouts, and more frequent sedentary bouts than boys. Similar results were observed in physical activities of each intensity as well as sedentary behavior variables, both on weekdays/weekends and during-school/after-school periods. These findings emphasize the importance of developing and implementing approaches to increase moderate to vigorous physical activity, as well as decrease prolonged sedentary time and long sedentary bouts, especially for Taiwanese girls.

The trajectory of patterns of light and sedentary physical activity among females, ages 14-23

PURPOSE

Light physical activity (LPA) and patterns of sedentary behavior influence cardio-metabolic health independently of moderate-to-vigorous physical activity. Understanding the trajectory and determinants of these activity levels over time may provide insights relevant to public health practice.

METHODS

We measured a cohort of young women recruited in middle school (age 14) using accelerometry for 1 week and remeasured them in high school (age 17) and again at age 23 (n = 385). We assessed changes in LPA and patterns of sedentary behavior by hours in a day. We examined the association of social and contextual factors, including employment status, screen time, and neighborhood context with LPA and sedentary behavior patterns.

RESULTS

The amount of LPA decreased over time, while the length of LPA bouts tended to increase. Sedentary bout durations increased over time and sedentary breaks decreased. Sedentary time and bout length were correlated with internet use, rather than with TV or videogaming. Employment was associated with less sedentary time; being a student was associated with longer sedentary time and bouts.

CONCLUSIONS

Because LPA and sedentary breaks can be protective for cardio-metabolic health, and the duration of sedentary bouts increase as women age from adolescence to young adulthood, worksites and college campuses should remind employees and students to take frequent activity breaks when they use computers and the internet for long stretches.

Substituting prolonged sedentary time and cardiovascular risk in children and youth: a meta-analysis within the International Children's Accelerometry database (ICAD)

BACKGROUND

Evidence on the association between sitting for extended periods (i.e. prolonged sedentary time (PST)) and cardio-metabolic health is inconsistent in children. We aimed to estimate the differences in cardio-metabolic health associated with substituting PST with non-prolonged sedentary time (non-PST), light (LIPA) or moderate-to-vigorous physical activity (MVPA) in children.

METHODS

Cross-sectional data from 14 studies (7 countries) in the International Children's Accelerometry Database (ICAD, 1998-2009) was included. Accelerometry in 19,502 participants aged 3-18 years, together with covariate and outcome data, was pooled and harmonized. Iso-temporal substitution in linear regression models provided beta coefficients (95%CI) for substitution of 1 h/day PST (sedentary time accumulated in bouts > 15 min) with non-PST, LIPA or MVPA, for each study, which were meta-analysed.

RESULTS

Modelling substitution of 1 h/day of PST with non-PST suggested reductions in standardized BMI, but estimates were > 7-fold greater for substitution with MVPA (- 0.44 (- 0.62; - 0.26) SD units). Only reallocation by MVPA was beneficial for waist circumference (- 3.07 (- 4.47; - 1.68) cm), systolic blood pressure (- 1.53 (- 2.42; - 0.65) mmHg) and clustered cardio-metabolic risk (- 0.18 (- 0.3; - 0.1) SD units). For HDL-cholesterol and diastolic blood pressure, substitution with LIPA was beneficial; however, substitution with MVPA showed 5-fold stronger effect estimates (HDL-cholesterol: 0.05 (0.01; 0.10) mmol/l); diastolic blood pressure: - 0.81 (- 1.38; - 0.24) mmHg).

CONCLUSIONS

Replacement of PST with MVPA may be the preferred scenario for behaviour change, given beneficial associations with a wide range of cardio-metabolic risk factors (including adiposity, HDL-cholesterol, blood pressure and clustered cardio-metabolic risk). Effect estimates are clinically relevant (e.g. an estimated reduction in waist circumference of ≈1.5 cm for 30 min/day replacement). Replacement with LIPA could be beneficial for some of these risk factors, however with substantially lower effect estimates.

Associations of accelerometer-measured sedentary time, sedentary bouts, and physical activity with adiposity and fitness in children

Sedentary time (ST) has been inconsistently associated with adiposity and cardiorespiratory fitness in children in previous studies. We studied cross-sectional associations of ST, light physical activity (LPA), and moderate-to-vigorous physical activity (MVPA) with fat mass index (FMI) and cardiorespiratory fitness (estimated VO₂max). Associations were evaluated with and without considering pattern of ST by bout length. We measured ST and activity by a wrist-worn accelerometer, FMI by bioelectrical impedance, and VO₂max by Pacer test in 443 children (51.2% girls, 10.2 ± 0.6 years). Isotemporal substitution regression models estimated the effects of substituting ST, LPA, and MVPA on FMI and VO₂max. Further models repeated analyses separating ST into short (<10 min) and long (≥10 min) bouts. Only replacing ST or LPA with MVPA was consistently associated with lower FMI and greater VO₂max. When separated by bout length, only one unique association was found where replacing long ST bouts with short ST bouts was associated with lower FMI in girls only. In conclusion, activity pattern is associated with adiposity in girls and fitness in boys and girls. Separating ST into long and short ST bouts may be of minimal importance when assessing associations with adiposity and fitness using wrist-worn accelerometry in children.

Associations between the Home Physical Environment and Children's Home-Based Physical Activity and Sitting

It is important to understand the correlates of children's physical activity (PA) and sitting at home, where children spend significant time. The home social environment has an important influence; however, much less is known about the home physical environment. Therefore, the study aimed to assess relationships between the physical environment and children's sitting and PA at home. In total, 235 child-parent dyads were included in the analyses. Children spent 67% of their time at home sitting. Linear regression analyses examined associations between physical home environmental factors obtained via an audit and children's (55% girl, 10.2 ± 0.7) objective PA and sitting at home. Following adjustment for socio-demographics and social environmental factors, an open plan living area (OPLA), musical instrument accessibility and availability, and perceived house size were negatively and positively associated, whereas media equipment accessibility and availability was positively and negatively associated with sitting and standing, respectively. Additionally, an OPLA was positively associated with total and moderate-to-vigorous PA. Furthermore, sitting breaks were positively associated with objective garden size and negatively associated with digital TV. The physical home environment may have an important influence on children's sitting, standing and PA at home; therefore, interventions that target this environment are needed.

SEDENTARY BEHAVIOR AND CARDIOVASCULAR RISK IN CHILDREN: A SYSTEMATIC REVIEW

ABSTRACT In recognition of the increasing time spent in sedentary activities in modern life, an emerging area of study linking sedentary time to health has highlighted its role in the development of chronic diseases. Therefore, the objective of this systematic review was to investigate the indicators and characteristics of sedentary behavior associated with cardiovascular risk factors in children and adolescents. The databases SciVerse Scopus, MEDLINE®/PubMed and LILACS were selected as a source of reference, using the associated terms “sedentary lifestyle” or “sedentary behavior” or “sedentary” AND “cardiovascular diseases” AND “child or adolescent” to identify studies published from January 2006 to March 2019. The methodological quality of the studies was evaluated and a score was assigned. Fifty articles were included in this review at the end. Extensive sedentary time, especially greater screen and TV exposure time, were associated with cardiovascular risk factors. In addition, the accumulation of prolonged sedentary bouts with few breaks in sedentary time tended to compromise the cardiometabolic profile. These findings highlight the importance of differentiating and considering these various indicators and characteristics of sedentary behavior. Further studies are needed to elucidate the multiple and overlapping facets of sedentary behavior and their relationship with health, and to encourage the development of evidence-based recommendations for this population. Level of Evidence I; Systematic Review of Level I Studies.

Edmonton Obesity Staging System for Pediatrics, quality of life and fitness in adolescents with obesity

BACKGROUND

Body mass index (BMI) is often used to diagnose obesity in childhood and adolescence but has limitations as an index of obesity-related morbidity. The Edmonton Obesity Staging System for Pediatrics (EOSS-P) is a clinical staging system that uses weight-related comorbidities to determine health risk in paediatric populations. The purpose of this study was to investigate the associations of EOSS-P and BMI percentile with quality of life (QOL), cardiorespiratory fitness (CRF) and muscular strength in adolescents with obesity.

METHODS

Participants were enrolled at baseline in the Healthy Eating, Aerobic and Resistance Training in Youth trial (BMI = 34.6 ± 4.5 kg m-2, age = 15.6 ± 1.4 years, N = 299). QOL, CRF (peak oxygen uptake, VO2peak) and muscular strength were assessed by the Pediatric QOL Inventory (PedsQL), indirect calorimetry during a maximal treadmill test and eight-repetition maximum bench and leg press tests, respectively. Participants were staged from 0 to 3 (absent to severe health risk) according to EOSS-P. Associations were assessed using age-adjusted and sex-adjusted general linear models.

RESULTS

Quality of life decreased with increasing EOSS-P stages (p < 0.001). QOL was 75.7 ± 11.4 in stage 0/1, 69.1 ± 13.1 in stage 2 and 55.4 ± 13.0 in stage 3. BMI percentile was associated with VO2peak (β = -0.044 mlO2 kg-1 min-1 per unit increase in BMI percentile, p < 0.001), bench press (β = 0.832 kg per unit increase in BMI percentile, p = 0.029) and leg press (β = 3.992 kg, p = 0.003). There were no significant differences in treadmill time or VO2peak between EOSS-P stages (p > 0.05).

CONCLUSION

As EOSS-P stages increase, QOL decreases. BMI percentile was negatively associated with CRF and positively associated with muscular strength.

Maternal BMI Change Linked to Child Activity Change in Family-Based Behavioral Interventions for Pediatric Weight Management

Background: This study investigated whether change in maternal BMI was associated with change in child's moderate-to-vigorous physical activity (MVPA) and prolonged sedentary time during the course of family-based behavioral interventions (FBBIs) for pediatric weight management. Methods: Children (n = 120) ages 5-12 [mean age = 9.04 ± 1.7) years with a baseline BMI ≥85th percentile (mean BMIz = 1.8 ± 0.5) and families were enrolled in one of three similar FBBIs for pediatric weight management and followed over 6-12 months. Activity data were collected through accelerometers. Mixed effects regression models assessed the relationship of maternal change in BMI to child change in (1) minutes/d of MVPA and (2) proportion of time spent in sedentary bouts lasting ≥10 minutes (termed prolonged sedentary time), and whether the effect of maternal BMI change was moderated by child age, sex, and race/ethnicity. Results: A decrease in maternal BMI was associated with both an increase in child MVPA, B = -2.77, t = -2.03, p = 0.048, and a decrease in proportion/d of prolonged sedentary time, B = 0.02, t = 2.40, p = 0.020, from baseline to follow-up. Child age moderated the association between maternal BMI change and change in child prolonged sedentary time (p = 0.095), whereby the association was limited to 5- to 10-year-olds and became stronger as age decreased. Conclusions: Improvement in maternal BMI showed important positive associations with child MVPA and prolonged sedentary time over the course of FBBIs for pediatric weight management. Targeting parent weight loss could improve child outcomes in FBBIs, particularly in younger children.