Inhibition Difficulties and Cyberbullying Perpetration in Alpha Generation Elementary School Students: The Moderating Role of Moderate-to-Vigorous Physical Activity and Gender

To compare the physical activity patterns of a cohort of Mexican children in kindergarten (K), first (1ES) and second grade (2ES) of elementary school. The physical activity of 217 children (123 girls and 94 boys) aged 5-6 years was measured (five full-day triaxial accelerometry) annually.Weekday and weekend moderate/ vigorous physical activity (MVPA) and school and off-school MVPA was calculated. Comparisons between surveys were made using longitudinal multilevel generalized linear models. Weekday MVPA was 22 and 37 min/d lower for 1ES (p=0.06) and 2ES (p<0.01), respectively, compared to K. School MVPA for 1ES and 2ES was 37 (-5.0 min/h) and 40% (-5.5 min/h) (p<0.001) lower, respectively, compared to K. No differences were found between weekend and off-school MVPA among school stages (p>0.5). MVPA was significantly reduced from K to ES,in part because of a decline in MVPA during school activities. Interventions targeted to school environment modifications should be promoted.

Background: Sedentary behaviour has detrimental health consequences, distinct from those of physical inactivity. An individual can be both highly active and highly sedentary: While the displacement hypothesis proposes that time spent active displaces time that would otherwise be spent sedentary, the compensation hypothesis suggests that increased physical activity (PA) may be associated with increased sedentary behaviour (SED) in non-active time. Objectives: The aim was to assess whether higher levels of childhood participation in moderate to vigorous PA (MVPA) are associated with higher levels of SED, or whether time spent in SED is displaced by higher levels of MVPA. Methods: Participants were 290 boys and 245 girls aged 8–10 years in the QUebec Adipose and Lifestyle InvesTigation in Youth (QUALITY) study. PA and SED were assessed by accelerometer over a 1-week period (SED ≤ 100 cpm, MVPA ≥ 2296 cpm), and quantified as mean time spent per day. Total PA was the sum of light PA + MVPA. Self-reported data included sports participation (number of teams), television viewing and computer/video game use (hours/day). Spearman correlations and multiple linear regression (adjusting for age, sex, body mass index, Tanner stage, parental education, accelerometer wear-time) were used to assess associations between PA and SED variables. Results: Higher MVPA and VPA were negatively correlated with SED (r=−0.44 and −0.35; p&lt;0.001), and positively correlated with total PA (r=0.58 and 0.45; p&lt;0.001). SED was negatively correlated with TPA (r=−0.65, p&lt;0.001). Only weak correlations were found between MVPA and sports participation, the latter not associated with SED. MVPA and VPA were not significantly correlated with TV, computer/video or total screen time; objectively measured SED was only weakly associated with specific sedentary behaviours. On average, for each additional 10 minutes of MVPA, children spent 14 minutes less in SED, or for each additional 5 minutes of VPA, 10 minutes less in SED. Associations were stronger in overweight/obese children compared to healthy weight children. Conclusions: Higher levels of MVPA in children displace SED, and are also associated with higher total PA over and above the additional amount of MVPA. The SED displacement benefits of higher MVPA may be greatest in overweight/obese children. Public health strategies should focus on both increasing PA and decreasing SED as essential targets to improve overall PA in children.

To describe active and sedentary time in children with spina bifida and to compare their physical activity on weekdays versus weekends. In this exploratory cross-sectional study, data from 13 Canadian and 22 Dutch children with spina bifida (14 females, 21 males; mean age 10y 11mo, standard deviation [SD] 3y 6mo, range 5y 6mo-18y; Hoffer classification distribution: community [n=28], household [n=3], non-functional [n=3], and non-ambulator [n=1]) were analysed. Objective measures of physical activity and sedentary behaviour were obtained by using ActiGraph or Actiheart activity monitors. Data for the participants wearing the ActiGraph were compared with age- and sex-matched controls that were developing typically using independent-samples t-tests. Activity data collected on weekdays was compared to those on weekends. ActiGraph data demonstrated children with spina bifida spent more time sedentary (mean [SD] 49.5min/h [5.78]) and less time in moderate to vigorous physical activity (mean [SD] 2.33min/h [1.61]) compared with the typically developing group (mean [SD] 41.0min/h [5.76] and 5.46min/h [2.13], p=0.001 and p<0.001 respectively). For both ActiGraph- and Actiheart-derived data, physical activity and sedentary time were not significantly different between weekdays and weekends. Children with spina bifida have reduced levels of physical activity and increased sedentary behaviour, with no statistical differences seen between weekdays and weekends. Several methodological issues related to activity monitoring warrant consideration when choosing the appropriate method to quantify physical activity and sedentary behaviour. Reduced levels of physical activity and sedentary time were quantified in children with spina bifida. Objective quantification of physical behaviour in ambulatory and non-ambulatory school-aged children with spina bifida is possible.

Background: Participation in at least 150 minutes/week of moderate-intensity aerobic activity is suggested for postpartum women. However, few women engage in these recommended levels of physical activity after pregnancy. To inform the development of interventions aimed at maintaining or increasing physical activity in the postpartum period, it is important to understand which factors are associated with postpartum physical activity. Methods: We examined the correlates of self-reported moderate to vigorous physical activity (MVPA) at 3- and 12-months postpartum among a cohort of women in the Pregnancy, Infection, and Nutrition Postpartum study. Women self-reported the frequency, duration, and mode of MVPA. Potential correlates were identified according to the socioecological framework and included sociodemographics, behavioral characteristics, non-recreational modes of MVPA (assessed only for recreational MVPA), reproductive history, infant care, psychosocial factors, and barriers to MVPA. Logistic regression models with GEE were used to identify correlates of any MVPA (≥10 minutes/week across all modes of activity) and any recreational MVPA (≥10 minutes/week) among women at 3-months (n=667) and 12-months (n=530) postpartum. Results: At both time points, lower odds of participation in any MVPA were associated with lower education, breastfeeding, depression, and minimal emotional support. Low confidence in exercise ability, receipt of advice about physical activity, and warmer seasons were associated with higher odds of participation in any MVPA. Associations varied by time point for two correlates. Low poverty and odds of any MVPA were negatively associated at 3-months and positively associated at 12-months postpartum. History of preeclampsia and odds of any MVPA were positively associated at 3-months and negatively associated at 12-months postpartum. For recreational MVPA at both time points, lower odds of participation were associated with unmarried status, lower education, employment, low poverty, history of preeclampsia, and minimal emotional support. Involvement in child/adult care activities and warmer seasons were associated with higher odds of participation in any recreational MVPA. Associations varied by time point for two correlates. Transportation MVPA and odds of any recreational MVPA were positively associated at 3-months and negatively associated at 12-months postpartum. Moderate stress and odds of any recreational MVPA were negatively associated at 3-months and positively associated at 12-months postpartum. Conclusion: These findings suggest that there are several modifiable factors associated with participation in MVPA in the postpartum period. Selected associations varied by time point. This information should be considered when developing interventions to help women maintain or increase physical activity following pregnancy.

To determine the predictors of magnitude of change in response to a participation-focused leisure-time physical activity intervention in children with cerebral palsy (CP) using the ParticiPAte CP protocol. We included 33 children (16 males, 17 females) aged 8 to 12years (mean age=10y, SD=1y 6mo) with CP with pre/postintervention data from a wait-list randomized trial. The hypothesized linear predictors of change in primary outcomes (Canadian Occupational Performance Measure [COPM]-performance and COPM-satisfaction, Belief in Goal Self-Competence Scale (BiGSS), and minutes per day moderate-to-vigorous physical activity [MVPA]) were: age; Gross Motor Function Classification System level; comorbid autism spectrum disorder (ASD); Goal Attainment Scaling T score; Problems in Schools Questionnaire; Physical Activity Climate Questionnaire; Motives for Physical Activities Measure-Revised; and stage of behaviour change. Multivariable models were selected using the Bayesian information criterion. Overcoming barriers to participation, age, and comorbid ASD explained 49% of the variance in change in COPM-performance. Being motivated by interest and/or enjoyment and age explained 32% of the variance in change in COPM-satisfaction. Being motivated by physical activity competence or appearance (extrinsic motivation) explained 24% of the variance in change in BiGSS. Parental autonomy supportiveness, overcoming barriers to participation, appearance motivation, and baseline MVPA explained 59% of the variance in change in MVPA. These findings support a behaviour paradigm for conceptualizing physical activity in children with CP. Children who met their treatment goals showed a greater increase in physical activity participation. Children who were more intrinsically motivated by physical activity at baseline improved more. Being older and having a comorbid diagnosis of autism spectrum disorder were associated with an attenuated effect of the therapy.

This study applies self-determination theory (SDT) to test the hypothesised relationships amongst three basic psychological needs, level of self-determined motivation (i.e. self-determination index, SDI) and moderate-to-vigorous physical activity (MVPA) of Chinese elementary and secondary school students during their physical education (PE) in Shanghai, China. Gender and school-level differences in these relationships are also explored. The participants comprise 1829 students from three elementary and secondary schools in Shanghai, China. Accelerometers are used to measure the MVPA duration of the participants in PE. The Self-regulation Questionnaire and the Psychological Needs Satisfaction Scale are completed by the participants to assess PE motivation and the three psychological needs of students. The structural equation modelling (SEM) results show that the hypothesised model has a good fit with our data. Autonomy, competence, and relatedness are positively associated with SDI for MVPA. The SDI is positively related to the time spent by students in MVPA in PE. The multi-group path analysis results reveal that the relationship between SDI and MVPA is stronger for secondary school students than elementary students. Overall, our findings support the applicability of SDT in understanding and promoting the physical activities amongst Chinese school students in PE. Accordingly, intervention should be conducted to develop autonomy, competence and social relatedness of elementary and secondary school students. Additional efforts are required to encourage elementary school students to be more self-determinant in PE classes. Highlights Findings support the applicability of SDT in understanding and promoting the physical activities amongst Chinese school students in PE SDI was positively related to school students’ MVPA level. The satisfaction of autonomy, competence and relatedness towards PE was positively associated with students’ SDI. The proposed motivational sequence for adolescent MVPA in PE were similar for male and female students. The relationship between SDI and MVPA of secondary school students was significantly stronger than elementary school students

Neighborhood walkability, socioeconomic status (SES) and psychosocial factors have each been associated with physical activity. Yet few U.S. studies have examined whether neighborhood SES or individual factors moderate associations between neighborhood walkability and adolescent physical activity levels. Adolescent data (n=1,288) from the NCI Family Life, Activity, Sun and Healthy Eating (FLASHE) study was used. Minutes per day of moderate to vigorous physical activity (MVPA) were calculated using the self-reported Youth Activity Profile and a subsample of participant accelerometer data. Adolescent home address was geocoded and linked to U.S. Census data at varying street network buffer sizes. Neighborhoods were defined by a 400m buffer around each participant's home. Factor analysis of neighborhood population density and built environment features revealed three neighborhood factors associated with walkability: 1) high density and non-auto commutes, 2) older homes, and 3) short auto commutes. Neighborhood SES was measured using the Yost index derived from Census data and categorized into quintiles (1 = lowest SES; 5 = highest SES). Multiple linear regression examined associations between neighborhood walkability factors and adolescent MVPA, and interactions between these factors and 1) neighborhood SES and 2) physical activity self-efficacy. We controlled for age, gender, race/ethnicity, and parent education. Living in neighborhoods with higher density (B=7.3, p=0.003) and older homes (B= 4.7, p=0.007) were positively associated with MVPA. The positive association between living in a higher density neighborhood with more non-auto commutes and MVPA was stronger for those living in neighborhoods at the 2nd and 4th quintiles of neighborhood SES, compared with those in the lowest SES neighborhoods. Similarly, the association between living in a neighborhood with older homes and MVPA was stronger for those living in the 2nd SES quintile compared with the lowest SES. Physical activity self-efficacy was independently positively associated with MVPA (B=18.9, p&amp;lt;.0.001), but did not moderate associations between walkability and MVPA. Neighborhood factors associated with walkability were associated with adolescent MVPA in this national sample of U.S. adolescents. For adolescents living in some higher SES neighborhoods, the association between living in a high-density or older neighborhood and MVPA was strengthened, suggesting that the walkability experience, or types of physical activities engaged in, may potentially vary by neighborhood SES, and are independent of individual self-efficacy. Citation Format: Heather D'Angelo, Laura Dwyer, Linda Nebeling, April Oh. Neighborhood socioeconomic status but not individual self-efficacy moderates associations between neighborhood walkability and adolescent physical activity in the NCI geoFLASHE Study [abstract]. In: Proceedings of the Eleventh AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2018 Nov 2-5; New Orleans, LA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl):Abstract nr C013.

650 Background: Regular moderate to vigorous physical activity (MVPA) in patients with gastrointestinal (GI) cancers is associated with improved health outcomes, including greater quality of life and reduced fatigue and comorbidity. PA guidelines for cancer survivors recommend ≥150 minutes of MVPA per week for optimal health. Identifying GI oncology patients with low MVPA is important to tailor interventions aimed at increasing MVPA levels in this population. The “Exercise as a Vital Sign” (EVS) tool is a validated, two question assessment tool to quantify minutes per week (min/wk) of MVPA that was incorporated in the clinical rooming process at an academic GI oncology clinic. Here, we report characteristics of patients by amount of MVPA by EVS. Methods: Patient information was entered in the electronic medical record at a large, academic oncology clinic. Data from the first clinic visit where min/wk of MVPA EVS was collected were extracted and included demographics (e.g. age, sex, marital status, race), health status (body mass index (BMI), Eastern Cooperative Oncology Group (ECOG) performance status, comorbidities), cancer characteristics (primary tumor site, localized/metastatic, current treatment), and reason for the clinic visit. MVPA was divided into two groups based on the recommended guidelines: 0-149 min/wk (“low”) and ≥150 min/wk (“high”). Chi-square and t-tests were used to examine statistically significant differences. Results: Among 265 patients abstracted, EVS data were reported from 156 (59%) patients. Mean (standard deviation (SD)) age was 61 (13) years (range: 25-82). The primary cancer site was 35% colorectal, 23% pancreatic, 17% gastroesophageal, 10% neuroendocrine, and 15% other GI cancers. While gastroesophageal cancer patients reported high amounts of MVPA (mean (SD) = 268 (309) min/wk), comparisons with other cancer sites were not statistically different. Of the 156 with EVS data, 84 (54%) had low MVPA (mean (SD): 55 (49) min/wk) and 72 (46%) had high MVPA (mean (SD): 357 (244) min/wk). Demographic and cancer characteristics were similar across the two groups. Patients with high MVPA were more likely to have BMI 18.5-24.9 kg/m2 (56% vs. 31%) and less likely to have BMI ≥25 kg/m2 (40% vs.61%) compared to patients with low MVPA (p = 0.02). Patients with high vs. low MVPA were also more likely to have excellent performance status (ECOG 0; 47% vs. 24%, p &lt; 0.001). Conclusions: In this study, GI oncology patients not meeting PA guidelines for cancer survivors were more likely to be overweight/obese and have worse performance status. The EVS tool was an inexpensive and accessible measure of MVPA that can be used to identify patients with low MVPA for interventions targeted to improve health outcomes. A lack of statistical significance may be due to low power. At the conference, more data will be presented (̃1000 patient visits), including longitudinal data and MVPA by active chemotherapy regimen.

Introduction: Rural communities in the US face disproportionately higher rates of physical inactivity as well as coronary heart disease mortality, when compared to their urban and suburban counterparts. As such, increasing physical activity (PA) and reducing barriers to PA is critical in improving population health. Neighborhood characteristics have been shown to influence PA, but are understudied in rural communities. The current analysis: (1) describes PA patterns in rural mid-western communities, and (2) examines the associations of and interactions between individual and environmental correlates of objectively assessed weekly moderate to vigorous physical activity (MVPA) minutes. Hypotheses: Overall, we expected low levels of weekly MVPA in rural residents; with lower levels anticipated in female, older, and low-income participants. We also expected positive associations of favorable perceptions of the neighborhood environment, trail use, and self-efficacy for PA with weekly MVPA. Finally, the test of interactions between intrapersonal and perceived environmental factors in relation to weekly MVPA is exploratory. Methods: Telephone surveys were conducted with 280 adults in 14 rural southeast Missouri communities, who were also asked to wear accelerometer devices for seven days. Participants were recruited via address-based sampling, and at local community events. Participants self-reported demographic information (age, sex, income), individual level behavioral factors (self-efficacy for PA, trail use) and neighborhood environment perceptions (indoor recreational access, safety from traffic, home neighborhood environment). Weekly MVPA minutes were assessed using the accelerometry data. Generalized linear mixed models using a negative binomial distribution were used examining associations of and interactions between individual characteristics and environmental correlates with weekly MVPA (Analyses were conducted using STATA V15). Results: Participants had a weekly average of 97 minutes MVPA, with 21% meeting PA guidelines. Increased age and being female were significantly associated with lower weekly MVPA. Additionally, increased self-efficacy and trail use were significantly associated with higher weekly MVPA. When exploring interaction effects, there was a significant interaction between gender and safety from traffic. For females, increased perceived safety from traffic was associated with lower MVPA. Conclusions: Rural residents have low levels of PA with less than a quarter meeting PA guidelines (75 minutes of vigorous and/or 150 minutes of moderate PA per week). Specifically, female residents face disproportionately lower levels of MVPA, with only 75 weekly minutes compared to 135 weekly minutes in males. Promoting trail use and targeting self efficacy for PA, may be effective strategies for increasing PA in rural residents.

Metabolic syndrome (MetS) is highly prevalent in children and adolescents with obesity and places them at an increased risk of cardiovascular-related diseases. However, the associations between objectively measured movement-related behaviors and MetS diagnosis remain unexplored in youths with obesity. The aim was to compare profiles of sedentary (SED) time (more sedentary, SED+ vs. less sedentary, SED−), moderate to vigorous physical activity (MVPA) time (more active, MVPA+ vs. less active, MVPA−) and combinations of behaviors (SED−/MVPA+, SED−/MVPA−, SED+/MVPA+, SED+/MVPA−) regarding the MetS diagnosis. One hundred and thirty-four adolescents with obesity (13.4 ± 2.2 years) underwent 24 h/7 day accelerometry, waist circumference (WC), blood pressure (BP), high-density lipoprotein-cholesterol (HDL-c), triglycerides (TG) and insulin-resistance (IR) assessments. Cumulative cardiometabolic risk was assessed by using (i) MetS status (usual dichotomic definition) and (ii) cardiometabolic risk z-score (MetScore, mean of standardized WC, BP, IR, TG and inverted HDL-c). SED− vs. SED+ and MVPA+ vs. MVPA− had lower MetS (p < 0.01 and p < 0.001) and MetScore (p < 0.001). SED−/MVPA+ had the lowest risk. While SED and MVPA times were lower in SED−/MVPA− vs. SED+/MVPA+ (p < 0.001), MetScore was lower in SED−/MVPA− independently of body mass index (BMI) (p < 0.05). MVPA, but not SED, time was independently associated with MetS diagnosis (p < 0.05). Both MVPA (p < 0.01) and SED times (p < 0.05) were associated with MetScore independently of each other. A higher MVPA and lower SED time are associated with lower cumulative cardiometabolic risk.

Moderate to vigorous physical activity (MVPA) is associated with positive physical and psychological health outcomes, yet youth with visual impairments tend to not to engage in sufficient MVPA. The purposes of this study were to (a) examine how familial factors were associated with MVPA among youth with visual impairments, their siblings, and parents and (b) examine the daily MVPA correlation among these family members. Twenty-two familial triads, including one child with a visual impairment, participated in this study. Accelerometers were used to measure MVPA and individual and familial factors were reported via questionnaire. Of the individual and familial factors measured, only family member role significantly predicted MVPA (β = .43, p < .01), as parents accumulated significantly more activity than their children (f2 = .22). The MVPA of children with visual impairments and their siblings were positively correlated (r = .39), while small negative relationships were found between MVPA of parents and children with and without visual impairments (r = -.16; r = -.33, respectively). In contrast with earlier findings, parents in the current study were significantly more active than their children with or without visual impairments. Potential reasons for this difference included the homogeneity of the sample, including a relatively high mean income level and parent education, which may have alleviated some typically reported barriers to parental MVPA. Future inquiries in this area should examine individual- and family-level factors concurrently to better understand their impact on MVPA within the familial triad.

Purpose: Mammographic density (MD) reflects the proportion of dense tissue in relation to non-dense tissue in the breast and is the strongest biological marker of breast cancer risk. MD is known to be higher among women with a family history compared to women in the general population. We have previously demonstrated that women with a strong family history of breast cancer but no BRCA mutation face an elevated lifetime risk of breast cancer estimated at 40% compared to 11% in the general population. Various lifestyle factors, such as physical activity and body mass index (BMI), have been shown to modify MD in the general population. It is of interest to determine if such an association exists among high-risk women. Objective: To evaluate the relationship between physical activity, BMI and MD in high-risk women. Methods: This study included 100 women enrolled in an on-going prospective study of high-risk women with a strong family history of breast cancer (two first-degree relatives with breast cancer under age 50 or three cases at any age) and no identified BRCA mutations in their families. Current physical activity levels and BMI were collected using self-reported questionnaires. Physical activity was defined as moderate to vigorous physical activity (MVPA). Two dichotomous variables were created to define high vs. low MVPA levels: 1) based on the Canadian Society for Exercise Physiology guideline of 2.5 hours of MVPA per week and 2) the 75th percentile of MVPA in the sample (3.5 hours per week). A BMI of 25 or more was defined as high using the World Health Organization criteria of overweight. Mammograms were assigned a percentage of density (0 - 100%) using a computer-assisted method (Cumulus 6). Multivariate linear regression modelling was used to evaluate the relationships between both MVPA and BMI with MD while adjusting for age, menopausal status, and parity. BMI models also adjusted for MVPA (continuous) and MVPA models adjusted for BMI (continuous). Results: Among all women, those with a high BMI had significantly lower mean percent density compared to women with a low BMI (13% vs. 23%; P = 0.01). This association was stronger for premenopausal (27% vs. 37%; P = 0.06) vs. postmenopausal (12% vs. 20%; P = 0.10) women. Women who engaged in MVPA for 2.5 hours per week or more had significantly greater mean percent density compared to women who were less physically active (29% vs. 22%; P = 0.04). This relationship did not vary by menopausal status (P ≥ 0.15). Based on the 75th percentile of MVPA, women with high MVPA levels had significantly greater mean percent density compared to women with low MVPA levels (31% vs. 22%; P = 0.02). This relationship was significant for postmenopausal (26% vs. 13%; P = 0.04) but not premenopausal (31% vs. 25%; P = 0.27) women. Conclusion: In this cohort of high-risk women, high BMI was associated with lower MD that was suggestively stronger for premenopausal women. Although preliminary, these findings suggest a possible mechanism by which a lifestyle factor may influence MD, and possibly breast cancer risk, in high-risk women. Further evaluation with a larger sample size is needed to elucidate the relationships between physical activity, as well as other modifiable factors, and MD in this cohort of women. This study adds to the growing evidence supporting the inclusion of MD into breast cancer risk prediction models, in order to improve individualized treatments and prevention strategies for women at an increased risk for disease. Citation Format: Olivia M. Moran, Dina Nikitina, Anoma Gunasekara, Martin J. Yaffe, Kelly A. Metcalfe, Steven A. Narod, Joanne Kotsopoulos. The effect of physical activity and body size on mammographic density in high-risk, BRCA mutation-negative women. [abstract]. In: Proceedings of the AACR Special Conference: Improving Cancer Risk Prediction for Prevention and Early Detection; Nov 16-19, 2016; Orlando, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2017;26(5 Suppl):Abstract nr B12.

Physical literacy and enjoyment are important factors that affect physical activity. This work studies whether physical activity enjoyment (PAE) mediates the association between moderate to vigorous physical activity (MVPA) and physical literacy (PL) among college students. Chinese college students were recruited using the Perceived Physical Literacy Instrument Scale (PPLI-SC), the International Physical Activity Questionnaire Short Form (IPAQ-SF), and the Physical Activity Enjoyment Scale. The SPSS Hayes process macro (model 4) was used to analyze the direct impact and the indirect impact. Pearson correlation, independent sample t-tests, and linear regression were used to analyze the relationship between indicators. The study surveyed 587 boys and 1,393 girls with a total of 1,980 valid questionnaires. MVPA, PAE, and PL of boys were significantly higher than girls (p < 0.01). The correlation analysis showed that MVPA, PL, and PAE were significantly correlated (p < 0.01). The results showed the direct effect of PL on MVPA was still statistically significant (β = 0.067, p < 0.05) after adding PAE variables; PAE has a positive effect on MVPA after controlling PL (β = 0.170, p < 0. 01). PL has a positive effect on PAE (β = 0.750, p < 0.01). PL impacted MVPA as explained by a 65.58% mediating effect of enjoyment. Physical activity enjoyment mediates the relationship between PL and MVPA among college students. This means that even high PL among student may not imply that they are physically active if they do not enjoy physical activity.

Relationships between movement-related behaviours and metabolic health remain underexplored in adolescents with obesity. To compare profiles of sedentary time (more sedentary, SED+ vs. less sedentary, SED-), moderate to vigorous physical activity (MVPA) time (more active, MVPA+ vs. less active, MVPA-) and combinations of behaviours (SED-/MVPA+, SED-/MVPA-, SED+/MVPA+, SED+/MVPA-) in regard to metabolic health. One hundred and thirty-four subjects (mean age 13.4± 2.2 yrs, mean body mass index [BMI] 98.9± 0.7 percentile, 48.5% females) underwent 24 h/7 day accelerometry, anthropometric, body composition, blood pressure (BP), lipid profile and insulin resistance (IR) assessments. Metabolic health was better in SED- [lower fat mass (FM) percentage (p < 0.05), blood pressure (BP) (p < 0.05), homeostasis model assessment of insulin resistance (HOMA-IR) (p < 0.001) and metabolic syndrome risk score (MetScore) (p < 0.001), higher high-density lipoprotein-cholesterol (HDL-c) (p=0.001)] vs. SED+ group and in MVPA+ [lower triglyceridemia (TG), (p < 0.05), HOMA-IR (p < 0.01) and MetScore (p < 0.001), higher HDL-c (p < 0.01)] vs. MVPA- group after adjustment with age, gender, maturation and BMI. SED-/MVPA+ group had the best metabolic health. While sedentary (p < 0.001) but also MVPA times (p < 0.001) were lower in SED-/MVPA- vs. SED+/MVPA+, SED-/MVPA- had lower FM percentage (p < 0.05), HOMA-IR (p < 0.01) and MetScore (p < 0.05) and higher HDL-c (p < 0.05), independently of BMI. Sedentary time was positively correlated with HOMA-IR and Metscore and negatively correlated with HDL-c after adjustment with MVPA (p < 0.05). MVPA was negatively correlated with HOMA-IR, BP and MetScore and positively correlated with HDL-c after adjustment with sedentary time (p < 0.05). Lower sedentary time is associated with a better metabolic health independently of MVPA and might be a first step in the management of pediatric obesity when increasing MVPA is not possible.

Background: It has been observed that physical activity patterns of health-related behavior are established in childhood and may continue into adulthood. Recent findings showing a relationship between the onset of chronic diseases and sedentary lifestyles support the importance of examining Moderate to Vigorous Physical Activity (MVPA). One instructional strategy that has been shown to correlate with higher physical activity levels in students at elementary school levels is the promotion of physical activity by teachers through verbal prompts, encouragement, and feedback. Purpose: To determine the functional relationship between distant interactions (a component of active monitoring where verbal interaction is given across the teaching environment) by physical education teachers and elementary students' MVPA levels during the physical fitness segment of their physical education class. Participants and setting: Five classes between Grades 3 and 5 (age range 8–10) and two elementary physical education teachers were observed for this study over 23–25 class sessions. Only the fitness segments were observed for this study. Intervention: Following a baseline phase, two conditions implemented and repeated across multiple class sessions. Condition C-IA (close interaction) consisted of the teachers only actively supervising those students in their immediate area (except for possible safety issues). During Condition D-IA (distant interaction) teachers also supervised actively, but only targeted their interactions to those students at fitness stations farthest removed from where they themselves were located. Research design: A reversal design using a baseline condition and two treatments, close interaction (C-IA) and distant interaction (D-IA) was implemented to demonstrate this relationship. Data collection: A modified System for Observing Fitness Instruction Time (SOFIT) and ‘live’ momentary time sampling along with videotape recordings were used to measure students' MVPA during fitness activities. Data analysis: The MVPA data were plotted graphically and analyzed visually, using data overlap, change in level, trends within and across phases, and variability within and across phases as the criteria to determine the functional relationship between the teacher's supervision techniques and the students' MVPA levels. Both session means and phase means were calculated for all conditions. Findings: Results indicated the teachers' use of distant interaction increased the MVPA levels for the students farthest from the teacher while the close students maintained their MVPA levels. Conclusions: Teachers need to be aware of the benefits of using distant interactions as part of their active supervision efforts to increase/sustain students' MVPA during fitness activities as part of the process aimed at shaping physical activity behavior in youth.