Policy determinants of physical activity across the life course: a 'DEDIPAC' umbrella systematic literature review.

Background: Despite the large number of studies and reviews available, the evidence regarding the policy determinants of physical activity (PA) is inconclusive. This umbrella systematic literature review (SLR) summarizes the current evidence on the policy determinants of PA across the life course, by pooling the results of the available SLRs and meta-analyses (MAs). Methods: A systematic online search was conducted on MEDLINE, ISI Web of Science, Scopus and SPORTDiscus databases up to April 2016. SLRs and MAs of observational studies investigating the association between policy determinants of PA and having PA as outcome were considered eligible. The extracted data were assessed based on the importance of the determinants, the strength of evidence and the methodological quality. Results: Fourteen reviews on 27 policy determinants of PA were eligible for this umbrella SLR. The majority of the reviews were of moderate quality. Among children, a clear association between time spent outdoors and PA emerged. Among adults, working hours were negatively associated with PA, though evidence was limited. At the population level, community- and street-scale urban design and land use policies were found to positively support PA levels, but levels of evidences were low. Conclusions: With this umbrella SLR the policy determinants of PA at individual-level and population-level have been summarized and assessed. None of the investigated policy determinants had a convincing level of evidence, and very few had a probable level of evidence. Further research is needed, preferably by using prospective study designs, standardized definitions of PA and objective measurement of PA.

Behavioral determinants of physical activity across the life course: a "DEterminants of DIet and Physical ACtivity" (DEDIPAC) umbrella systematic literature review.

BACKGROUND: Low levels of physical activity (PA) are a global concern and increasing PA engagement is becoming a priority in current public health policies. Despite the large number of studies and reviews available, the evidence regarding the behavioral determinants of PA is still inconclusive. Thus, the aim of this umbrella systematic literature review (SLR) was to summarize the evidence on the behavioral determinants of PA across the life course. METHODS: A systematic online search was conducted on MEDLINE, ISI Web of Science, Scopus, and SPORTDiscus databases. The search was limited to studies published in English from January, 2004 to April, 2016. SLRs and meta-analyses (MAs) of observational studies that investigated the behavioral determinants of PA were considered eligible. The extracted data were assessed based on the importance of the determinants, the strength of evidence, and the methodological quality. The full protocol is available from PROSPERO (PROSPERO 2014:CRD42015010616). RESULTS: Seventeen reviews on 35 behavioral determinants of PA were eligible for this umbrella SLR. Regardless of age, the most investigated determinants were those related with 'screen use' and 'smoking'. For youth, probable positive evidence emerged for 'previous PA' and 'independent mobility and active transport' among children and adolescents. For the adult population, 'transition to university' and 'pregnancy/having a child' showed probable negative associations. CONCLUSIONS: Although the majority of the evidence was limited and most of the determinants were not associated with PA, this umbrella SLR provided a comprehensive overview of the associations between behavioral determinants and PA. Youth should be physically active in the early years and increase active transportation to/from school, independent mobility, and 'free-range activities' without adult supervision, whilst adult PA behaviors are mostly influenced by the life events. Finally, more research is needed that incorporates prospective study designs, standardized definitions of PA, objective measurement methods of PA assessment, and the use of interactionist and mediational approaches for the evaluation of different behavioral determinants influencing PA behaviors.

Socio-cultural determinants of physical activity across the life course: a 'Determinants of Diet and Physical Activity' (DEDIPAC) umbrella systematic literature review.

OBJECTIVE: Regular physical activity (PA) reduces the risk of disease and premature death. Knowing factors associated with PA might help reducing the disease and economic burden caused by low activity. Studies suggest that socio-cultural factors may affect PA, but systematic overviews of findings across the life course are scarce. This umbrella systematic literature review (SLR) summarizes and evaluates available evidence on socio-cultural determinants of PA in children, adolescents, and adults. METHODS: This manuscript was drafted following the recommendations of the 'Preferred Reporting Items for Systematic reviews and Meta-Analyses' (PRISMA) checklist. The MEDLINE, Web of Science, Scopus, and SPORTDiscus databases were searched for SLRs and meta-analyses (MAs) on observational studies published in English that assessed PA determinants between January 2004 and April 2016. The methodological quality was assessed and relevant information on socio-cultural determinants and any associations with PA was extracted. The available evidence was evaluated based on the importance of potential determinants and the strength of the evidence. RESULTS: Twenty SLRs and three MAs encompassing 657 eligible primary studies investigated potential socio-cultural PA determinants, with predominantly moderate methodological quality. Twenty-nine potential PA determinants were identified that were primarily assessed in children and adolescents and investigated the micro-environmental home/household level. We found probable evidence that receiving encouragement from significant others and having a companion for PA were associated with higher PA in children and adolescents, and that parental marital status (living with partner) and experiencing parental modeling were not associated with PA in children. Evidence for the other potential determinants was limited, suggestive, or non-conclusive. In adults, quantitative and conclusive data were scarce. CONCLUSIONS: A substantial number of SLRs and MAs investigating potential socio-cultural determinants of PA were identified. Our data suggest that receiving social support from significant others may increase PA levels in children and adolescents, whereas parental marital status is not a determinant in children. Evidence for other potential determinants was limited. This was mainly due to inconsistencies in results on potential socio-cultural determinants of PA across reviews and studies. TRIAL REGISTRATIONS: This umbrella SLR was recorded on PROSPERO (Record ID: CRD42015010616 ).

The moderating effect of psychosocial factors in the relation between neighborhood walkability and children's physical activity.

BACKGROUND: The study aimed to investigate if psychosocial factors moderate the association between objective walkability and different domains of children's physical activity (PA). A second aim of the study was to investigate the direct associations between psychosocial factors and children's PA. Based on previous literature, it was hypothesized that walkability would be more strongly related to PA among children with negative psychosocial profiles. METHODS: Data were collected between December 2011 and May 2013 as part of the Belgian Environmental Physical Activity Study in children (BEPAS-child). In total, data from 494 children and one of their parents were included in the study. Children wore an accelerometer for 7 consecutive days and together with one of their parents, they completed the Flemish Physical Activity Questionnaire. Parents filled out a questionnaire concerning their child's psychosocial factors toward PA (i.e. parental attitude toward their child's PA, parental social norm toward their child's PA, parental support, friend support, children's self-efficacy, and perceived benefits and barriers toward sports and PA). Neighborhood walkability was calculated using geographical information systems (GIS). Multilevel cross-classified analyses were conducted. RESULTS: Of the 42 investigated interactions between neighborhood walkability and psychosocial factors in relation to PA among children, only 7 significant interactions were found of which 3 were only significant among children from low-income neighborhoods. Parental support and self-efficacy were positive correlates of children's PA in high- and low-income neighborhoods independent of the level of walkability, but effect sizes were small. CONCLUSIONS: The hypothesis that walkability would be more strongly related to PA among children with negative psychosocial profiles could not be confirmed and in general, psychosocial factors and objective walkability did not interact in relation to children's PA. Focusing on parental support and self-efficacy towards PA can possibly cause small effects on children's PA in both high- and low-walkable neighborhoods, as well as in high- and low-income neighborhoods.

Using an audit tool (MAPS Global) to assess the characteristics of the physical environment related to walking for transport in youth: reliability of Belgian data.

BACKGROUND: The aim was to examine inter-rater and alternate-form reliability of the Microscale Audit of Pedestrian Streetscapes (MAPS) Global tool to assess the physical environment along likely walking routes in Belgium. METHODS: For 65 children participating in the BEPAS-children study, routes between their individual homes and the nearest pre-defined destination were defined. Using MAPS Global, physical environmental characteristics of the routes were audited by 4 trained auditors (2 on-site, 2 online using Google Street View). Inter-rater reliability was studied for on-site and online ratings separately. Alternate-form reliability was examined by comparing on-site with online ratings. RESULTS: Inter-rater reliability for on-site ratings was acceptable for 68% of items (kappa range 0.03-1.00) and for online ratings for 60% of items (kappa range -0.03 to 1.00). Acceptable alternate-form reliability was reported for 60% of items (kappa range -0.01 to 1.00/r range 0.31-1.00). CONCLUSIONS: MAPS Global can be used to assess the physical environment of potential walking routes. For areas where Google Street View imagery is widely covered and often updated, MAPS Global can be completed online.

Changes in Individual and Social Environmental Characteristics in Relation to Changes in Physical Activity: a Longitudinal Study from Primary to Secondary School.

PURPOSE: Physical activity (PA) strongly decreases when children make the transition from primary to secondary school. The study aimed to investigate how individual and social environmental factors toward PA changed when children (11-12 years) made the transition from primary to secondary school (13-14 years) and how changes in these factors were related to changes in different PA domains. METHODS: In total, 321 children (48.9 % girls) and one of their parents both filled out a questionnaire concerning individual (i.e., attitude, self-efficacy, perceived benefits, and barriers of PA) and social environmental factors related to PA (parental support, friend's co-participation, parental trust in child's ability to be physically active, and social norm) in the last grade of primary school and 2 years later. Children wore an activity monitor for 7 days and self-reported different domains of PA. RESULTS: Most individual and social factors became less positive toward PA after the transition to secondary school. Among girls, a more positive attitude and an increase in self-efficacy were related to an increase in average daily steps and sports during leisure, respectively. Among boys, a decrease in perceived barriers (lack of time and parental reported lack of transportation to sport activities) was related to a decrease in average daily steps. An increase in parental support and a decrease in the parental perceived barrier of not liking sports were related to an increase in sports during leisure. CONCLUSIONS: The prevention of adverse changes in individual and social factors toward physical activity may lead to a smaller decrease or an increase in physical activity.

Organizing "Play Streets" during school vacations can increase physical activity and decrease sedentary time in children.

A Play Street is a street that is reserved for children's safe play for a specific period during school vacations. It was hypothesized that a Play Street near children's home can increase their moderate- to vigorous-intensity physical activity (MVPA) and decrease their sedentary time. Therefore, the aim of this study was to investigate the effect of Play Streets on children's MVPA and sedentary time.A nonequivalent control group pretest-posttest design was used to determine the effects of Play Streets on children's MVPA and sedentary time. Data were collected in Ghent during July and August 2013. The study sample consisted of 126 children (54 from Play streets, 72 from control streets). Children wore an accelerometer for 8 consecutive days and their parents fill out a questionnaire before and after the measurement period. During the intervention, streets were enclosed and reserved for children's play. Four-level (neighborhood - household - child - time of measurement (no intervention or during intervention)) linear regression models were conducted in MLwiN to determine intervention effects.Positive intervention effects were found for sedentary time (ß = -0.76 ± 0.39; χ(2) = 3.9; p = 0.05) and MVPA (ß = 0.82 ± 0.43; χ(2) = 3.6; p = 0.06). Between 14h00 and 19h00, MVPA from children living in Play Streets increased from 27 minutes during normal conditions to 36 minutes during the Play Street intervention, whereas control children's MVPA decreased from 27 to 24 minutes. Sedentary time from children living in the Play Street decreased from 146 minutes during normal conditions to 138 minutes during the Play Street intervention, whereas control children's sedentary time increased from 156 minutes to 165 minutes. The intervention effects on MVPA (ß = -0.62 ± 0.25; χ(2) = 6.3; p = 0.01) and sedentary time (ß = 0.85 ± 0.0.33; χ(2) = 6.6; p = 0.01) remained significant when the effects were investigated during the entire day, indicating that children did not compensate for their increased MVPA and decreased sedentary time, during the rest of the day.Creating a safe play space near urban children's home by the Play Street intervention is effective in increasing children's MVPA and decreasing their sedentary time.

Cross-continental comparison of the association between the physical environment and active transportation in children: a systematic review.

BACKGROUND: The purpose of this systematic review was to determine the relationship between a wide range of physical environmental characteristics and different contexts of active transportation in 6- to 12-year-old children across different continents. METHODS: A systematic search was conducted in six databases (Pubmed, Web of Science, Cinahl, SportDiscus, TRIS and Cochrane) resulting in 65 papers, eligible for inclusion. The investigated physical environmental variables were grouped into six categories: walkability, accessibility, walk/cycle facilities, aesthetics, safety, recreation facilities. RESULTS: The majority of the studies were conducted in North America (n = 35), Europe (n = 17) and Australia (n = 11). Active transportation to school (walking or cycling) was positively associated with walkability. Walking to school was positively associated with walkability, density and accessibility. Evidence for a possible association was found for traffic safety and all forms of active transportation to school. No convincing evidence was found for associations between the physical environment and active transportation during leisure. General safety and traffic safety were associated with active transportation to school in North America and Australia but not associated with active transportation to school in Europe. CONCLUSIONS: The physical environment was mainly associated with active transportation to school. Continent specific associations were found, indicating that safety measures were most important in relation to active commuting to school in North America and Australia. There is a need for longitudinal studies and studies conducted in Asia, Africa and South-America and studies focusing specifically on active transportation during leisure.

The influence of dairy consumption and physical activity on ultrasound bone measurements in Flemish children.

The study's aim was to analyse whether children's bone status, assessed by calcaneal ultrasound measurements, is influenced by dairy consumption and objectively measured physical activity (PA). Moreover, the interaction between dairy consumption and PA on bone mass was studied. Participants of this cross-sectional study were 306 Flemish children (6-12 years). Body composition was measured with air displacement plethysmography (BodPod), dairy consumption with a Food Frequency Questionnaire, PA with an accelerometer (only in 234 of the 306 children) and bone mass with quantitative ultrasound, quantifying speed of sound (SOS), broadband ultrasound attenuation (BUA) and Stiffness Index (SI). Regression analyses were used to study the associations between dairy consumption, PA, SOS, BUA and SI. Total dairy consumption and non-cheese dairy consumption were positively associated with SOS and SI, but no significant association could be demonstrated with BUA. In contrast, milk consumption, disregarding other dairy products, had no significant effect on calcaneal bone measurements. PA [vigorous PA, moderate to vigorous physical activity (MVPA) and counts per minute] was positively associated and sedentary time was negatively associated with BUA and SI, but no significant influence on SOS could be detected. Dairy consumption and PA (sedentary time and MVPA) did not show any interaction influencing bone measurements. In conclusion, even at young age, PA and dairy consumption positively influence bone mass. Promoting PA and dairy consumption in young children may, therefore, maximize peak bone mass, an important protective factor against osteoporosis later in life.

The association between the parental perception of the physical neighborhood environment and children's location-specific physical activity.

BACKGROUND: The relationship between children's physical neighborhood environment and their physical activity, has been largely investigated. However in recent reviews, only a few significant and consistent direct associations between children's physical neighborhood environment and their physical activity were found. This is possibly due to the fact that the location where children's physical activity took place, is insufficiently specified. Therefore, this study aimed to investigate the association between parental perceived neighborhood characteristics and children's physical activity in clearly defined environments. METHODS: Children (9-12 years; n = 606) wore an Actigraph accelerometer for 7 days. Parents completed the parental version of the Neighborhood Environmental Walkability Scale questionnaire and reported on children's physical activity in specific locations: physical activity in nearby streets and on sidewalks, physical activity in public recreation spaces and physical activity in the garden. Multilevel logistic regression analyses were conducted in MLwiN 2.30. RESULTS: Children were more likely to be active in nearby streets and on sidewalks, if their parents perceived lower street connectivity (OR = 0.479; 95% CI = 0.33 and 0.70), higher land use mix accessibility (OR = 1.704; 95% CI = 1.25 and 2.33) and more crime safety (OR = 1.879; 95% CI = 1.29 and 2.74). Children whose parents perceived higher presence of recreation facilities (OR = 1.618; CI = 1.23; 2.12) were more likely to be active in public recreation spaces. No environmental neighborhood variables were related to physical activity in the garden and overall moderate- to vigorous-intensity physical activity. CONCLUSIONS: The parental perceived physical neighborhood environment relates differently to physical activity in different locations. In order to develop effective interventions, it seems promising to further investigate the association between location-specific physical activity and specific neighborhood environmental correlates.

The influence of dairy consumption, sedentary behaviour and physical activity on bone mass in Flemish children: a cross-sectional study.

BACKGROUND: This cross-sectional study aimed to look for an association in young children between whole body bone mineral content (BMC) and areal bone mineral density (aBMD) and dairy consumption as well as sedentary behaviour (SB) and physical activity (PA). Moreover, we investigated whether there was an interaction effect between dairy consumption and SB or PA on BMC and aBMD. METHODS: Healthy children (6-12 years) were recruited from primary schools. Body composition and whole body bone mass were measured with dual-energy X-ray absorptiometry (DXA), dairy consumption was assessed with a food frequency questionnaire (FFQ) and PA and SB with an accelerometer. In total, 272 children underwent a DXA scan. Complete FFQ data were available for 264 children and 210 children had matching data from accelerometry recordings. Regression analyses were used to study the associations between (1) BMC and aBMD and (2) dairy consumption, SB and PA, adjusting for age, gender, pubertal stage, height and body composition. RESULTS: Dairy consumption was positively associated with whole body BMC and aBMD (absolute value as well as z-score), after correction for relevant confounders. SB was negatively associated with aBMD z-score and light PA was positively associated with both BMC and aBMD z-score. No gender differences were found. Moreover, an interaction effect between vigorous PA (VPA) and dairy consumption on aBMD (z-score) and BMC z-score was found, indicating that children with both high VPA and high dairy consumption had higher values for BMC and aBMD of the whole body minus the head. CONCLUSION: Already at young age, PA and dairy consumption positively influence whole body bone mass assessed by DXA. Moreover, this study indicates clearly that SB is negatively associated with whole body bone density. Promoting regular PA and sufficient dairy consumption in young children and limiting SB can be expected to positively influence their bone mass accumulation, which can help in the prevention of osteoporosis later in life.

Feasibility and effectiveness of drop-off spots to promote walking to school.

BACKGROUND: Drop-off spots are locations in the proximity of primary schools where parents can drop off or pick up their child. From these drop-off spots children can walk to and from school. This pilot study aimed to investigate the feasibility and effectiveness of drop-off spots and to evaluate how drop-off spots are perceived by school principals, teachers and parents of 6-to-12-year old children. METHODS: First, a feasibility questionnaire was completed (n = 216) to obtain parental opinions towards the implementation of drop-off spots. A drop-off spot was organized (500-800 m distance from school) in two primary schools. A within-subject design was used to compare children's (n = 58) step counts and number of walking trips during usual conditions (baseline) and during implementation of a drop-off spot (intervention). Three-level (class-participant-condition) linear regression models were used to determine intervention effects. After the intervention, 2 school principals, 7 teachers and 44 parents filled out a process evaluation questionnaire. RESULTS: Prior to the intervention, 96% expressed the need for adult supervision during the route to school. Positive significant intervention effects were found for step counts before/after school hours (+732 step counts/day; X2 = 12.2; p < 0.001) and number of walking trips to/from school (+2 trips/week; X2 = 52.9; p < 0.001). No intervention effect was found for total step counts/day (X2 = 2.0; p = 0.16). The intervention was positively perceived by the school principals and parents, but teachers expressed doubts regarding future implementation. CONCLUSION: This pilot study showed that implementing drop-off spots might be an effective intervention to promote children's walking to school. Implementing drop-off spots does not require major efforts from the schools and schools can choose how and when they organize drop-off spots. However, motivating teachers and involving other volunteers (e.g. parents, grandparents) may be needed. Future studies should investigate the feasibility and effectiveness of drop-off spots in a larger sample of schools.

The association between objective walkability, neighborhood socio-economic status, and physical activity in Belgian children.

BACKGROUND: Objective walkability is an important correlate of adults' physical activity. Studies investigating the relation between walkability and children's physical activity are scarce. However, in order to develop effective environmental interventions, a profound investigation of this relation is needed in all age groups. The aim of this study was to investigate the association between objective walkability and different domains of children's physical activity, and to investigate the moderating effect of neighborhood socio-economic status in this relation. METHODS: Data were collected between December 2011 and May 2013 as part of the Belgian Environmental Physical Activity Study in children. Children (9-12 years old; n = 606) were recruited from 18 elementary schools in Ghent (Belgium). Children together with one of their parents completed the Flemish Physical Activity Questionnaire and wore an accelerometer for 7 consecutive days. Children's neighborhood walkability was calculated using geographical information systems. Multilevel cross-classified modeling was used to determine the relationship between children's PA and objectively measured walkability and the moderating effect of neighborhood SES in this relation. RESULTS: In low SES neighborhoods walkability was positively related to walking for transportation during leisure time (ß = 0.381 ± 0.124; 95% CI = 0.138, 0.624) and was negatively related to sports during leisure time (ß = -0.245 ± 0.121; 95% CI = -0.482, -0.008). In high socio-economic status neighborhoods, walkability was unrelated to children's physical activity. No relations of neighborhood walkability and neighborhood socio-economic status with cycling during leisure time, active commuting to school and objectively measured moderate- to vigorous-intensity physical activity were found. CONCLUSIONS: No univocal relation between neighborhood walkability and physical activity was found in 9-12 year old children. Results from international adult studies cannot be generalized to children. There is a need in future research to determine the key environmental correlates of children's physical activity.

Effectiveness and feasibility of lowering playground density during recess to promote physical activity and decrease sedentary time at primary school.

BACKGROUND: This pilot study aimed at investigating the effectiveness of lowering playground density on increasing children's physical activity and decreasing sedentary time. Also the feasibility of this intervention was tested. METHODS: Data were collected in September and October 2012 in three Belgian schools in 187, 9-12 year old children. During the intervention, playground density was decreased by splitting up recesses and decreasing the number of children sharing the playground. A within-subject design was used. Children wore accelerometers during the study week. Three-level (class - participant - measurement (baseline or intervention)) linear regression models were used to determine intervention effects. After the intervention week the school principals filled out a questionnaire concerning the feasibility of the intervention. RESULTS: The available play space was 12.18 ± 4.19 m²/child at baseline and increased to 24.24 ± 8.51 m²/child during intervention. During the intervention sedentary time decreased (-0.58 min/recess; -3.21%/recess) and moderate-to-vigorous physical activity (+1.04 min/recess; +5.9%/recess) increased during recess and during the entire school day (sedentary time: -3.29%/school day; moderate-to-vigorous physical activity +1.16%/school day). All principals agreed that children enjoyed the intervention; but some difficulties were reported. CONCLUSIONS: Lowering playground density can be an effective intervention for decreasing children's sedentary time and increasing their physical activity levels during recess; especially in least active children.

Criterion distances and environmental correlates of active commuting to school in children.

BACKGROUND: Active commuting to school can contribute to daily physical activity levels in children. Insight into the determinants of active commuting is needed, to promote such behavior in children living within a feasible commuting distance from school. This study determined feasible distances for walking and cycling to school (criterion distances) in 11- to 12-year-old Belgian children. For children living within these criterion distances from school, the correlation between parental perceptions of the environment, the number of motorized vehicles per family and the commuting mode (active/passive) to school was investigated. METHODS: Parents (n = 696) were contacted through 44 randomly selected classes of the final year (sixth grade) in elementary schools in East- and West-Flanders. Parental environmental perceptions were obtained using the parent version of Neighborhood Environment Walkability Scale for Youth (NEWS-Y). Information about active commuting to school was obtained using a self-reported questionnaire for parents. Distances from the children's home to school were objectively measured with Routenet online route planner. Criterion distances were set at the distance in which at least 85% of the active commuters lived. After the determination of these criterion distances, multilevel analyses were conducted to determine correlates of active commuting to school within these distances. RESULTS: Almost sixty percent (59.3%) of the total sample commuted actively to school. Criterion distances were set at 1.5 kilometers for walking and 3.0 kilometers for cycling. In the range of 2.01 - 2.50 kilometers household distance from school, the number of passive commuters exceeded the number of active commuters. For children who were living less than 3.0 kilometers away from school, only perceived accessibility by the parents was positively associated with active commuting to school. Within the group of active commuters, a longer distance to school was associated with more cycling to school compared to walking to school. CONCLUSIONS: Household distance from school is an important correlate of transport mode to school in children. Interventions to promote active commuting in 11-12 year olds should be focusing on children who are living within the criterion distance of 3.0 kilometers from school by improving the accessibility en route from children's home to school.

Opinions towards physical activity interventions using Facebook or text messaging: Focus group interviews with vocational school-aged adolescents.

Feasible and effective interventions to promote physical activity among vocational school-aged adolescents are strongly needed. Text messaging and Facebook are feasible and acceptable delivery modes for PA interventions among youth. However, little is known about the opinion of vocational school-aged adolescents regarding behavioural change techniques that can be applied through Facebook or text messaging. Therefore, our aim was to gain insight into the opinions of vocational school-aged adolescents towards the use of different behaviour change techniques and towards Facebook/text messaging as a delivery mode for PA interventions. Six focus groups were conducted with 41 adolescents from the first grade (12-14 years) of secondary vocational schools in Flanders (Belgium). In total 41 adolescents participated and completed a questionnaire about their text messaging and Facebook use prior to group discussions. Focus group discussions were audio-recorded and analysed using a thematic analysis method in Nvivo. Participants thought that different behaviour change techniques (e.g., providing feedback, goal setting, self-monitoring, social comparison) could be integrated in a PA intervention using text messaging and Facebook and were enthusiastic about participating in such an intervention. They indicated that text messages are an easy way to receive information about PA, and that a group page on Facebook is ideal to share information with others. Participants deemed it very important that the group page on Facebook would only include peers with whom they also share an offline connection. Furthermore, adolescents stressed the importance of having autonomy (e.g., to determine their personal activity goals, to self-monitor their behaviour) and of being active together with friends. This qualitative study revealed that the use of Facebook and text messaging is promising as a delivery method for PA interventions among vocational school-aged adolescents. The adolescents were keen to participate in an intervention that integrates behaviour change techniques using text messaging or Facebook.

Biological determinants of physical activity across the life course: a "Determinants of Diet and Physical Activity" (DEDIPAC) umbrella systematic literature review.

BACKGROUND: Despite the large number of studies and reviews available, the evidence regarding the biological determinants of physical activity (PA) is inconclusive. In this umbrella review, we summarized the current evidence on the biological determinants of PA across the life course, by pooling the results of the available systematic literature reviews (SLRs) and meta-analyses (MAs). METHODS: We conducted an online search on MEDLINE, ISI Web of Science, Scopus, and SPORTDiscus databases up to January 2018. SLRs and MAs of observational studies that investigated the association between biological determinants of PA and having PA as outcome were considered eligible. The extracted data were assessed based on the importance of the determinants, the strength of evidence, and the methodological quality. RESULTS: We identified 19 reviews of which most were of moderate methodological quality. Determinants that were studied most frequently among all ages and demonstrated evidence suggesting a positive association to PA were younger age, being male, higher health status, and higher physical fitness levels. Among adults, normal birth weight was found to be positively associated to PA with convincing strength of evidence, while findings among adolescents were inconsistent and with limited strength of evidence. CONCLUSIONS: Different social or behavioral factors may contribute to the decrease of PA with age and among females versus males, and creating programmes targeted at diverse ages, female population, and adults with abnormal birth weight is recommended. Future studies should use prospective study designs, standardized definitions of PA, and objective measurement methods of PA assessment.

Socio-economic determinants of physical activity across the life course: A "DEterminants of DIet and Physical ACtivity" (DEDIPAC) umbrella literature review.

BACKGROUND: To date, the scientific literature on socioeconomic correlates and determinants of physical activity behaviours has been dispersed throughout a number of systematic reviews, often focusing on one factor (e.g. education or parental income) in one specific age group (e.g. pre-school children or adults). The aim of this umbrella review is to provide a comprehensive and systematic overview of the scientific literature from previously conducted research by summarising and synthesising the importance and strength of the evidence related to socioeconomic correlates and determinants of PA behaviours across the life course. METHODS: Medline, Embase, ISI Web of Science, Scopus and SPORTDiscus were searched for systematic literature reviews and meta-analyses of observational studies investigating the association between socioeconomic determinants of PA and PA itself (from January 2004 to September 2017). Data extraction evaluated the importance of determinants, strength of evidence, and methodological quality of the selected papers. The full protocol is available from PROSPERO (PROSPERO2014:CRD42015010616). RESULTS: Nineteen reviews were included. Moderate methodological quality emerged. For adults, convincing evidence supports a relationship between PA and socioeconomic status (SES), especially in relation to leisure time (positive relationship) and occupational PA (negative relationship). Conversely, no association between PA and SES or parental SES was found for pre-school, school-aged children and adolescents. CONCLUSIONS: Available evidence on the socioeconomic determinants of PA behaviour across the life course is probable (shows fairly consistent associations) at best. While some evidence is available for adults, less was available for youth. This is mainly due to a limited quantity of primary studies, weak research designs and lack of accuracy in the PA and SES assessment methods employed. Further PA domain specific studies using longitudinal design and clear measures of SES and PA assessment are required.

A life course examination of the physical environmental determinants of physical activity behaviour: A "Determinants of Diet and Physical Activity" (DEDIPAC) umbrella systematic literature review.

BACKGROUND: Participation in regular physical activity is associated with a multitude of health benefits across the life course. However, many people fail to meet PA recommendations. Despite a plethora of studies, the evidence regarding the environmental (physical) determinants of physical activity remains inconclusive. OBJECTIVE: To identify the physical environmental determinants that influence PA across the life course. METHODS: An online systematic literature search was conducted using MEDLINE, ISI Web of Science, Scopus and SPORTDiscus. The search was limited to studies published in English (January 2004 to April 2016). Only systematic literature reviews (SLRs) and meta-analyses (MAs) of observational studies, that investigated the association between physical determinants and physical activity outcomes, were eligible for inclusion. The extracted data were assessed on the importance of determinants, strength of evidence and methodological quality. RESULTS: The literature search identified 28 SLRs and 3 MAs on 67 physical environmental characteristics potentially related to physical activity that were eligible for inclusion. Among preschool children, a positive association was reported between availability of backyard space and outdoor toys/equipment in the home and overall physical activity. The availability of physical activity programs and equipment within schools, and neighbourhood features such as pedestrian and cyclist safety structure were positively associated with physical activity in children and adolescents. Negative street characteristics, for example, lack of sidewalks and streetlights, were negatively associated with physical activity in adults. Inconsistent associations were reported for the majority of reviewed determinants in adults. CONCLUSION: This umbrella SLR provided a comprehensive overview of the physical environment determinants of physical activity across the life course and has highlighted, particularly amongst youth, a number of key determinants that may be associated with overall physical activity. Given the limited evidence drawn mostly from cross-sectional studies, longitudinal studies are needed to further explore these associations. REGISTRATION: PROSPERO CRD42015010616.

Psychological determinants of physical activity across the life course: A "DEterminants of DIet and Physical ACtivity" (DEDIPAC) umbrella systematic literature review.

Low levels of physical activity (PA) are reported to contribute to the occurrence of non-communicable diseases over the life course. Although psychological factors have been identified as an important category concerning PA behavior, knowledge on psychological determinants of PA is still inconclusive. Therefore, the aim of this umbrella systematic literature review (SLR) was to summarize and synthesize the scientific evidence on psychological determinants of PA behavior across the life course. A systematic online search was conducted on MEDLINE, ISI Web of Science, Scopus, and SPORTDiscus databases. The search was limited to studies published in English from January 2004 to April 2016. SLRs and meta-analyses (MAs) of observational studies investigating the association of psychological variables and PA were considered eligible. Extracted data were evaluated based on importance of determinants, strength of evidence, and methodological quality. The full protocol is available from PROSPERO (Record ID: CRD42015010616). Twenty reviews (14 SLRs and 6 MAs), mostly of moderate methodological quality, were found eligible. Convincing evidence was found for self-efficacy (positive association with PA) in children and adolescents, and stress (negative association with PA) regardless of age. Most of the evidence revealing an association between psychological determinants and PA is probable and limited, mainly due to differences in the definition of PA and of psychological determinants across reviews. Thus, scholars are urged to reach a consensus on clear definitions of relevant psychological determinants of PA, subsuming cultural biases and allowing the possibility to obtain clear interpretations and generalizability of findings. Finally, most psychological determinants should be considered within a larger framework of other multi-level determinants that may interact or mediate some of the effects.