Ilse De Bourdeaudhuij

Ghent University, Gand, Flemish, Belgium

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Publications (462)1193.81 Total impact

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    ABSTRACT: Occupational sitting can be the largest contributor to overall daily sitting time in white-collar workers. With adverse health effects in adults, intervention strategies to influence sedentary time on a working day are needed. Therefore, the present aim was to examine employees' and executives' reflections on occupational sitting and to examine the potential acceptability and feasibility of intervention strategies to reduce and interrupt sedentary time on a working day. Seven focus groups (four among employees, n = 34; three among executives, n = 21) were conducted in a convenience sample of three different companies in Flanders (Belgium), using a semi-structured questioning route in five themes [personal sitting patterns; intervention strategies during working hours, (lunch) breaks, commuting; and intervention approach]. The audiotaped interviews were verbatim transcribed, followed by a qualitative inductive content analysis in NVivo 10. The majority of participants recognized they spend their working day mostly sitting and associated this mainly with musculoskeletal health problems. Participants suggested a variety of possible strategies, primarily for working hours (standing during phone calls/meetings, PC reminders, increasing bathroom use by drinking more water, active sitting furniture, standing desks, rearranging the office) and (lunch) breaks (physical activity, movement breaks, standing tables). However, several barriers were reported, including productivity concerns, impracticality, awkwardness of standing, and the habitual nature of sitting. Facilitating factors were raising awareness, providing alternatives for simply standing, making some strategies obligatory and workers taking some personal responsibility. There are some strategies targeting sedentary time on a working day that are perceived to be realistic and useful. However several barriers emerged, which future trials and practical initiatives should take into account.
    International Journal of Behavioral Nutrition and Physical Activity 12/2015; 12(1). DOI:10.1186/s12966-015-0177-5 · 3.68 Impact Factor
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    ABSTRACT: Women living in deprived neighborhoods are a risk group for overweight and obesity, particularly during the childbearing years. Several socio-demographic characteristics may compound this risk, but little is known about why this might be the case. Sedentary behaviors are emerging as a socio-demographically patterned risk factor for obesity. The purpose of the present study was to assess socio-demographic differences in sedentary behaviors, and to examine whether these behaviors could explain the relation between socio-demographic variables and BMI (BMI) in this risk group. Women aged 18-46 years were recruited from 40 urban and 40 rural deprived neighborhoods in Victoria, Australia. In total, 3879 women reported socio-demographic variables (age, educational level, employment status, marital status, number of children, residential location and country of birth), sedentary behaviors (television time, computer time, total screen time and total sedentary time), physical activity, and height and weight, which were used to calculate BMI. For each socio-demographic variable, four single mediation models were conducted using two-level mixed-models regression analyses. Mediating effects were examined using the MacKinnon product-of-coefficients procedure and the Sobel test. All socio-demographic variables were significantly associated with sedentary behaviors. Single mediation analyses revealed that television time (αβ = 0.017, 95% CI = 0.000, 0.030) and total screen time (αβ = 0.006, 95% CI = 0.000, 0.012) mediated 14.1% and 4.9% of the relationship between educational level and BMI, respectively. Total screen time mediated 45.1% of the relationship between employment status and BMI (αβ = -0.020, 95% CI = -0.033, -0.006), and television time mediated 8.2% of the relationship between country of birth and BMI (αβ = -0.008, 95% CI = -0.016, -0.001). Sedentary behaviors differed depending on socio-demographic characteristics, and partly explained the relationship between socio-demographic factors and BMI in this sample of women. Both television time and total screen time are potential behaviors to target in future programs aimed at reducing socio-demographic disparities in overweight and obesity.
    International Journal of Behavioral Nutrition and Physical Activity 12/2015; 12(1). DOI:10.1186/s12966-015-0209-1 · 3.68 Impact Factor
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    Benedicte Deforche · Delfien Van Dyck · Tom Deliens · Ilse De Bourdeaudhuij
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    ABSTRACT: The transition to higher education involves a significant life change and might be accompanied with less healthy behaviours. However, the only longitudinal study that spanned the period from high school to college/university was limited to self-reported weight. Other studies assessed objective weight, but only at the start of the first semester at college/university and used retrospective questionnaires to asses health behaviours in high school. This study investigated changes in objectively assessed weight and prospective health behaviours during the transition from high school to college/university in Belgian students and examined which health behaviour changes were related to weight change. A sample of 291 students was followed from the final year of high school until the second year of college/university. Body mass index (BMI) and waist circumference were measured objectively. Physical activity, sedentary behaviours and dietary intake were estimated using validated questionnaires. In order to study changes in BMI and health behaviours, 2 × 2 (time × gender) Repeated Measures ANOVA analyses were conducted. A stepwise multiple regression analysis was executed to investigate the association between changes in health behaviours and BMI changes, and the moderating effect of gender. On average students gained 2.7 kg with a greater increase in boys (boys: 4.2 kg, girls: 1.9 kg). Active transportation and sport participation decreased. Some sedentary behaviours (watching TV/DVD, playing computer games) decreased, while others (internet use, studying) increased. Consumption of different foods decreased, while alcohol consumption increased. A higher decrease in sport participation, a higher increase in internet use and a lower increase in studying were related to a greater increase in BMI. An increase in alcohol consumption only contributed to weight gain in boys, whereas a decrease in fruit/vegetable intake only contributed to weight gain in girls. We can conclude that the transition to higher education is an at risk period for weight gain and unfavourable changes in health behaviours. Interventions to prevent weight gain in college/university students should therefore already start in high school with a somewhat different focus in boys versus girls.
    International Journal of Behavioral Nutrition and Physical Activity 12/2015; 12(1). DOI:10.1186/s12966-015-0173-9 · 3.68 Impact Factor
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    Tom Deliens · Benedicte Deforche · Ilse De Bourdeaudhuij · Peter Clarys
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    ABSTRACT: College or university is a critical period regarding unhealthy changes in energy related behaviours in students. The first objective of this explorative study was to identify determinants of physical activity and sedentary behaviour in Belgian university students. Secondly, we aimed to collect ideas and recommendations to increase physical activity and decrease sedentary behaviours in university students. Using a semi-structured question guide, seven focus group discussions were conducted consisting of 17 male and 29 female university students from a variety of study disciplines, with a mean age of 20.7 ± 1.6 yrs. Using Nvivo9, an inductive thematic approach was used for data analysis. Students reported that both physical and sedentary activities were influenced by individual factors (e.g. perceived enjoyment, self-discipline, time and convenience), their social networks (e.g. (lack of) parental control, modelling, social support), physical environment (e.g. availability and accessibility, travel time/distance, prices), and macro environment (e.g. media and advertising). Furthermore, the relationships between determinants and university students' physical activity and sedentary behaviour seemed to be moderated by university characteristics, such as residency, university lifestyle, exams and academic pressure. Recommendations for future physical activity interventions include improving information strategies regarding on-campus sports activities, cheaper and/or more flexible sports subscriptions and formulas, including 'sports time' into the curricula, and providing university bicycles around campus. Students also believed that increasing students' physical activity might decrease their sedentary behaviour at the same time. The recommendations and ideas discussed in this study may facilitate the development of effective and tailored (multilevel) intervention programs aiming to increase physical activity and decrease sedentary behaviours in university students.
    BMC Public Health 12/2015; 15(1):1553. DOI:10.1186/s12889-015-1553-4 · 2.32 Impact Factor
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    Sara D'Haese · Delfien Van Dyck · Ilse De Bourdeaudhuij · Benedicte Deforche · Greet Cardon
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    ABSTRACT: 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 (β = -0.76 ± 0.39; χ2 = 3.9; p = 0.05) and MVPA (β = 0.82 ± 0.43; χ2 = 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 (β = -0.62 ± 0.25; χ2 = 6.3; p = 0.01) and sedentary time (β = 0.85 ± 0.0.33; χ2 = 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.
    International Journal of Behavioral Nutrition and Physical Activity 12/2015; 12(1):171. DOI:10.1186/s12966-015-0171-y · 3.68 Impact Factor
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    ABSTRACT: School educators play an important role in cyberbullying management. Since scarce earlier research indicated low perceived competence of school educators in handling cyberbullying, more insight is needed in what determines their actions and how to improve these practices. This study assessed school educator practices, their perceptions and context factors from a behavior change theoretical framework, and investigated educator clusters related to this. An online survey was conducted among 451 secondary school educators (teachers, principals, school counselors). School educators mostly used recommended actions (i.e. conversations with pupils, enlisting professionals for support, parental involvement, providing supportive victim advice). Four educator clusters were identified: 'referrers' (65%), 'disengaged' educators (14%), 'concerned' educators (12%) and 'use all means' educators (9%). The first two clusters were less adept at handling cyberbullying and comprised mostly teachers, particularly indicating a need for training teachers. Our findings show a need for tailored educator training, e.g. by job position, gender, school size and grade. The behavior change theoretical framework can help target educators' particular needs.
    Computers & Education 10/2015; 88:192-201. DOI:10.1016/j.compedu.2015.05.006 · 2.63 Impact Factor
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    ABSTRACT: Insights into the diurnal patterns of sedentary behavior and the identification of subgroups that are at increased risk for engaging in high levels of sedentary behavior are needed to inform potential interventions for reducing older adults' sedentary time. Therefore, we examined the diurnal patterns and sociodemographic correlates of older adults' sedentary behavior(s). Stratified cluster sampling was used to recruit 508 non-institutionalized Belgian older adults (≥ 65 years). Morning, afternoon, evening and total sedentary time was assessed objectively using accelerometers. Specific sedentary behaviors, total sitting time and sociodemographic attributes were assessed using an interviewer-administered questionnaire. Participants self-reported a median of 475 (Q1-Q3 = 383-599) minutes/day of total sitting time and they accumulated a mean of 580 ± 98 minutes/day of accelerometer-derived sedentary time. Sedentary time was lowest during the morning and highest during the evening. Older participants were as sedentary as younger participants during the evening, but they were more sedentary during daytime. Compared to married participants, widowers were more sedentary during daytime. Younger participants (< 75 years), men and the higher educated were more likely to engage in (high levels of) sitting while driving a car and using the computer. Those with tertiary education viewed 29% and 22% minutes/day less television compared to those with primary or secondary education, respectively. Older participants accumulated 35 sedentary minutes/day more than did younger participants and men accumulated 32 sedentary minutes/day more than did women. These findings highlight diurnal variations and potential opportunities to tailor approaches to reducing sedentary time for subgroups of the older adult population.
    PLoS ONE 08/2015; 10(8):e0133175. DOI:10.1371/journal.pone.0133175 · 3.23 Impact Factor
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    ABSTRACT: This study investigated moderating effects of psychosocial factors on the association between walkability and physical activity (PA) in 433 Belgian older adults. Furthermore, main effects of psychosocial factors on PA were determined. No moderating effects were observed for the associations between walkability and transport walking, or moderate-to-vigorous PA (MVPA). Walkability was positively associated with recreational walking in those with high self-efficacy. Regarding main effects, benefits and social norm were positively associated with recreational walking. Benefits were positively and barriers were negatively associated with MVPA. There were no significant main effects for transport walking. The overall lack of moderation suggests that environmental interventions might enhance all older adults' transport walking and MVPA. Recreational walking might be enhanced by simultaneously targeting self-efficacy and neighborhood environmental factors. Copyright © 2015. Published by Elsevier Ltd.
    Health & Place 07/2015; 34. DOI:10.1016/j.healthplace.2015.05.004 · 2.44 Impact Factor
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    ABSTRACT: Online social networks offer considerable potential for delivery of socially influential health behavior change interventions. To determine the efficacy, engagement, and feasibility of an online social networking physical activity intervention with pedometers delivered via Facebook app. A total of 110 adults with a mean age of 35.6 years (SD 12.4) were recruited online in teams of 3 to 8 friends. Teams were randomly allocated to receive access to a 50-day online social networking physical activity intervention which included self-monitoring, social elements, and pedometers ("Active Team" Facebook app; n=51 individuals, 12 teams) or a wait-listed control condition (n=59 individuals, 13 teams). Assessments were undertaken online at baseline, 8 weeks, and 20 weeks. The primary outcome measure was self-reported weekly moderate-to-vigorous physical activity (MVPA). Secondary outcomes were weekly walking, vigorous physical activity time, moderate physical activity time, overall quality of life, and mental health quality of life. Analyses were undertaken using random-effects mixed modeling, accounting for potential clustering at the team level. Usage statistics were reported descriptively to determine engagement and feasibility. At the 8-week follow-up, the intervention participants had significantly increased their total weekly MVPA by 135 minutes relative to the control group (P=.03), due primarily to increases in walking time (155 min/week increase relative to controls, P<.001). However, statistical differences between groups for total weekly MVPA and walking time were lost at the 20-week follow-up. There were no significant changes in vigorous physical activity, nor overall quality of life or mental health quality of life at either time point. High levels of engagement with the intervention, and particularly the self-monitoring features, were observed. An online, social networking physical activity intervention with pedometers can produce sizable short-term physical activity changes. Future work is needed to determine how to maintain behavior change in the longer term, how to reach at-need populations, and how to disseminate such interventions on a mass scale. Australian New Zealand Clinical Trials Registry (ANZCTR): ACTRN12614000488606; (Archived by WebCite at
    Journal of Medical Internet Research 07/2015; 17(7):e174. DOI:10.2196/jmir.4086 · 4.67 Impact Factor
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    International Congres of Transport & Health, London; 07/2015
  • Nicole Gunther · Ann DeSmet · Niels Jacobs · Ilse De Bourdeaudhuij
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    ABSTRACT: This chapter describes the current research on the negative outcomes of traditional and cyberbullying concerning psychological health, physical health, social functioning, and behaviour problems. They explore these problems from the perspective of bullies, victims, bully/victims, and bystanders, and discuss whether the impact of cyberbullying compared to traditional bullying on the outcomes is equal, less, or more severe. Furthermore, they discuss the interrelatedness between (cyber-)bullying and negative (health) outcomes.
    Cyberbullying: From Theory to Interventions, Edited by Trijntje Vollinck, Francine Dehue, Connar McGuckin, 07/2015: chapter 4: pages 54-81; Psychology Press.
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    ABSTRACT: Dietary patterns, physical activity (PA) and sedentary behaviours are some of the main behavioural determinants of obesity; their combined influence in children has been addressed in a limited number of studies. Children (16 228) aged 2-9 years old from eight European countries participated in the baseline survey of the IDEFICS study. A subsample of 11 674 children (50.8% males) were included in the present study. Children's food and beverage consumption (fruit and vegetables (F&V) and sugar-sweetened beverages (SSBs)), PA and sedentary behaviours were assessed via parental questionnaires. Sex-specific cluster analysis was applied to identify behavioural clusters. Analysis of covariance and logistic regression were applied to examine the association between behavioural clusters and body composition indicators (BCIs). Six behavioural clusters were identified (C1-C6) both in boys and girls. In both sexes, clusters characterised by high level of PA (C1 and C3) included a large proportion of older children, whereas clusters characterised by low SSB consumption (C5 and C6) included a large proportion of younger children. Significant associations between derived clusters and BCI were observed only in boys; those boys in the cluster with the highest time spent in sedentary activities and low PA had increased odds of having a body mass index z-score (odds ratio (OR)=1.33; 95% confidence interval (CI)=(1.01, 1.74)) and a waist circumference z-score (OR=1.41; 95%CI=(1.06, 1.86)) greater than one. Clusters characterised by high sedentary behaviour, low F&V and SSB consumption and low PA turned out to be the most obesogenic factors in this sample of European children.European Journal of Clinical Nutrition advance online publication, 3 June 2015; doi:10.1038/ejcn.2015.76.
    European journal of clinical nutrition 06/2015; 69(7). DOI:10.1038/ejcn.2015.76 · 2.95 Impact Factor
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    Sara D'Haese · Delfien Van Dyck · Ilse De Bourdeaudhuij · Benedicte Deforche · Greet Cardon
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    ABSTRACT: 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. 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. 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. 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.
    BMC Public Health 06/2015; 15(1):565. DOI:10.1186/s12889-015-1937-5 · 2.32 Impact Factor
  • T Deliens · B Deforche · I De Bourdeaudhuij · P Clarys
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    ABSTRACT: This study examined changes in Belgian students' weight, body composition and physical fitness after 1.5 years at university. Furthermore, this study investigated whether these changes differed by gender and weight status. In this longitudinal study, 172 students' weight, body mass index (BMI) and waist circumference (WC) were objectively measured, whereas fat%, fat mass, fat-free mass, dynamic leg strength, handgrip strength, hamstring flexibility and cardiorespiratory fitness were estimated using validated instruments. Measurements were conducted at the start of the first semester (T0), after the first semester (T1) and after 1.5 years (T2) at university. Female students' weight and BMI did not change, whereas male students gained 2.7 kg of weight and showed a 0.7 kg/m(2) BMI increase after 1.5 years. After the first semester, an increase in fat% was observed in the total group of students, whereas this time effect did not remain significant when comparing T0 and T2. In contrast to females, increases in 2.1 kg of fat-free mass and 1.8 cm of WC were found in males after 1.5 years. Higher baseline BMI and WC predicted greater BMI and fat% increases in males. Handgrip strength improved for both sexes, whereas no changes in other physical fitness components were found across the 1.5-year period. The greatest weight and BMI gains as well as unfavourable changes in body composition were found in male students with higher baseline BMI and WC. The observed changes in body composition did not cohere with changes in physical fitness.European Journal of Clinical Nutrition advance online publication, 27 May 2015; doi:10.1038/ejcn.2015.79.
    European journal of clinical nutrition 05/2015; DOI:10.1038/ejcn.2015.79 · 2.95 Impact Factor
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    ABSTRACT: Ecological models of health behaviour are an important conceptual framework to address the multiple correlates of obesity. Several single-country studies previously examined the relationship between the built environment and obesity in adults, but results are very diverse. An important reason for these mixed results is the limited variability in built environments in these single-country studies. Therefore, the aim of this study was to examine associations between perceived neighbourhood built environmental attributes and BMI/weight status in a multi-country study including 12 environmentally and culturally diverse countries. A multi-site cross-sectional study was conducted in 17 cities (study sites) across 12 countries (Australia, Belgium, Brazil, China, Colombia, Czech Republic, Denmark, Mexico, New Zealand, Spain, the UK and USA). Participants (n = 14222, 18-66 years) self-reported perceived neighbourhood environmental attributes. Height and weight were self-reported in eight countries, and measured in person in four countries. Three environmental attributes were associated with BMI or weight status in pooled data from 12 countries. Safety from traffic was the most robust correlate, suggesting that creating safe routes for walking/cycling by reducing the speed and volume of traffic might have a positive impact upon weight status/BMI across various geographical locations. Close proximity to several local destinations was associated with BMI across all countries, suggesting compact neighbourhoods with more places to walk related to lower BMI. Safety from crime showed a curvilinear relationship with BMI, with especially poor crime safety being related to higher BMI. Environmental interventions involving these three attributes appear to have international relevance and focusing on these might have implications for tackling overweight/obesity.
    International Journal of Behavioral Nutrition and Physical Activity 05/2015; 12(1):62. DOI:10.1186/s12966-015-0228-y · 3.68 Impact Factor
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    ABSTRACT: As physical activity levels decrease as children age, sustainable and accessible forms of physical activity are needed from a young age. Transportation cycling is one such physical activity and has been associated with many benefits. The aims of the study were to identify whether manipulating micro-environmental factors (e.g. speed limis, evenness of cycle path) within a photographed street influences the perceived supportiveness for transportation cycling; and whether changing these micro-environmental factors has the same effect across different street settings. We recruited 305 fifth and sixth grade children and their parents from twelve randomly selected primary schools in Flanders, Belgium. They completed a web-based questionnaire including 12 choice-based conjoint tasks, in which they had to choose between two possible routes depicted on manipulated photographs, which the child would cycle along. The routes differed in four attributes: general street setting (enclosed, half open, open), evenness of cycle path (very uneven, moderately uneven, even), speed limit (70 km/h, 50 km/h, 30 km/h) and degree of separation between a cycle path and motorised traffic (no separation, curb, hedge). Hierarchical Bayes analyses revealed the relative importance of each micro-environmental attribute across the three street settings. For each attribute, children and their parents chose routes that had the best alternative (i.e. open street setting, even cycle path, 30 km/h, a hedge separating the cycle path from motorised traffic). The evenness of the cycle path and lower speed limit had the largest effect for the children, while the degree of separation and lower speed limit had the largest effect for their parents. Interactions between micro-scale and macro-scale factors revealed differences in the magnitude but not direction of their effects on route choice. The results held across the different kinds of street settings tested. Improving micro-scale attributes may increase the supportiveness of a street for children's transportation cycling. We call for on-site research to test effects of changes in micro-environmental attributes on transportation cycling among children.
    International Journal of Behavioral Nutrition and Physical Activity 05/2015; 12(1):54. DOI:10.1186/s12966-015-0216-2 · 3.68 Impact Factor
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    ABSTRACT: As cyberbullying is a phenomenon that is inherently social, the normative social influence of significant others can play an important role in the behaviour of adolescents involved in cyberbullying incidents. Using data from 525 adolescent bystanders of cyberbullying, we created a path model in order to investigate whether injunctive and descriptive norms of certain reference groups can cause bystanders to experience social pressure and join in cyberbullying. The results showed that social pressure fully mediated the relationship between the injunctive norm of friends approving of cyberbullying and joining in cyberbullying as a bystander. Furthermore, both the injunctive norm of parents approving of cyberbullying and bystanders’ involvement in cyberbullying perpetration were related to joining in cyberbullying as a bystander.
    Review of Social Development 05/2015; DOI:10.1111/sode.12134 · 1.56 Impact Factor
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    ABSTRACT: Adequate monitoring of older adults' physical activity (PA) is essential to develop effective health promotion programs. The present study examined criterion validity and test-retest reliability of the long International Physical Activity Questionnaire (IPAQ-L), adapted for Belgian, community-dwelling older adults (65y and older). Participants (n = 434) completed the last seven days version of IPAQ-L, modified for the Belgian population of community-dwelling older adults. This elderly-adapted version of IPAQ-L combined vigorous and moderate activities, and questions on gait speed and recreational cycling were added. Furthermore, participants wore an ActiGraph GT3X(+) accelerometer for at least five days. Criterion validity was determined by comparing self-reported weekly minutes of moderate-to-vigorous physical activity (MVPA) and weekly minutes of total PA with accelerometer data, defined by two different cut points (Freedson vs. Copeland). To examine test-retest reliability, a subsample of 29 participants completed IPAQ-L for a second time within a ten day interval. IPAQ-L showed moderate criterion validity for measuring weekly minutes of MVPA (Spearman's ρ range 0.33- and total PA (Spearman's ρ range 0.33-0.40) However, plots on agreement between self-reported and accelerometer PA showed a systematic over-reporting of IPAQ-L for MVPA. In contrast, plots indicated that IPAQ-L under-estimated levels of total PA, however, this under-estimation of total PA was substantially lower than the observed over-reporting of MVPA. Test-retest reliability was moderate-to-good for work-related PA, domestic PA, MVPA and total PA (ICC range 0.52-0.81), but poorer for transportation and recreational PA (ICC 0.44 and 0. 43, respectively). Criterion validity results suggest that IPAQ-L is more valid to measure older adults' weekly minutes of total PA than weekly MVPA minutes. Moreover, results might imply that content validity of IPAQ-L can be improved if specific light-intensity PA items are incorporated into IPAQ-L. Test-retest reliability of IPAQ-L was moderate to good, except for weekly minutes of transportation and recreational PA, probably due to week-to-week variability of these behaviors.
    BMC Public Health 04/2015; 15(1):433. DOI:10.1186/s12889-015-1785-3 · 2.32 Impact Factor
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    ABSTRACT: Relapse is high in lifestyle obesity interventions involving behavior and weight change. Identifying mediators of successful outcomes in these interventions is critical to improve effectiveness and to guide approaches to obesity treatment, including resource allocation. This article reviews the most consistent self-regulation mediators of medium- and long-term weight control, physical activity, and dietary intake in clinical and community behavior change interventions targeting overweight/obese adults. A comprehensive search of peer-reviewed articles, published since 2000, was conducted on electronic databases (for example, MEDLINE) and journal reference lists. Experimental studies were eligible if they reported intervention effects on hypothesized mediators (self-regulatory and psychological mechanisms) and the association between these and the outcomes of interest (weight change, physical activity, and dietary intake). Quality and content of selected studies were analyzed and findings summarized. Studies with formal mediation analyses were reported separately. Thirty-five studies were included testing 42 putative mediators. Ten studies used formal mediation analyses. Twenty-eight studies were randomized controlled trials, mainly aiming at weight loss or maintenance (n = 21). Targeted participants were obese (n = 26) or overweight individuals, aged between 25 to 44 years (n = 23), and 13 studies targeted women only. In terms of study quality, 13 trials were rated as "strong", 15 as "moderate", and 7 studies as "weak". In addition, methodological quality of formal mediation analyses was "medium". Identified mediators for medium-/long-term weight control were higher levels of autonomous motivation, self-efficacy/barriers, self-regulation skills (such as self-monitoring), flexible eating restraint, and positive body image. For physical activity, significant putative mediators were high autonomous motivation, self-efficacy, and use of self-regulation skills. For dietary intake, the evidence was much less clear, and no consistent mediators were identified. This is the first systematic review of mediational psychological mechanisms of successful outcomes in obesity-related lifestyle change interventions. Despite limited evidence, higher autonomous motivation, self-efficacy, and self-regulation skills emerged as the best predictors of beneficial weight and physical activity outcomes; for weight control, positive body image and flexible eating restraint may additionally improve outcomes. These variables represent possible targets for future lifestyle interventions in overweight/obese populations.
    BMC Medicine 04/2015; 13(1):84. DOI:10.1186/s12916-015-0323-6 · 7.28 Impact Factor
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    Ann DeSmet · Ross Shegog · Dimitri Van Ryckeghem · Geert Crombez · Ilse De Bourdeaudhuij
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    ABSTRACT: Serious games may be effective in promoting sexual health behavior. Their confidential nature may encourage users to discuss sensitive sexuality topics. Furthermore, they can tailor messages to the individual's needs and may be intrinsically motivating. This meta-analysis investigates the effectiveness of interventions for sexual health promotion that use serious games. A database search was conducted in PubMed, Web of Science, CINAHL, and PsycINFO for publications before the end of July 2013. Serious digital games studies measuring effects on behavior or its determinants, using a control condition, allowing the calculation of an effect size (Hedges' g, random-effects model) were included. Seven game studies for sexual health promotion were included. These showed positive effects on determinants (g=0.242; 95 percent confidence interval, 0.129, 0.356), albeit of small effect size. The effects on behavior, measured in only two studies, were not significant (g=0.456; 95 percent confidence interval, -0.649, 1.561). Most games did not use many game features that are considered to be immersive or enhancing flow. Instead, there was a strong reliance on pure gamification features, such as rewards and feedback. The effectiveness of the next generation of games may be enhanced by building on the behavioral change and educational gaming literatures (e.g., using role-play and simulation game formats, individual tailoring, offering adaptation in the difficulty of the challenge, and amount and timing of the feedback). There is a need for studies with rigorous evaluations of game effectiveness, longer-term follow-up, and using measures of behavior rather than merely their determinants.
    04/2015; 4(2). DOI:10.1089/g4h.2014.0110

Publication Stats

9k Citations
1,193.81 Total Impact Points


  • 1997–2015
    • Ghent University
      • • Department of Experimental Clinical and Health Psychology
      • • Department of Movement and Sports Sciences
      • • Faculty of Psychology and Educational Sciences
      Gand, Flemish, Belgium
  • 2013
    • University of Maiduguri
      • Department of Physiotherapy
      Maidugari, Borno, Nigeria
  • 2012
    • University of Antwerp
      • Department of Communication Studies
      Antwerpen, Flemish, Belgium
  • 2011
    • University of Granada
      • Department of Medicine
      Granata, Andalusia, Spain
  • 2010
    • University of Applied Sciences Coburg
      Landkreis Coburg, Bavaria, Germany
    • Universiteit Hasselt
      • Faculty of Business Economics (BEW)
      Flanders, Belgium
  • 2008
    • University of Leuven
      • Department of Human Kinesiology
      Louvain, Flanders, Belgium
  • 2007
    • Erasmus Universiteit Rotterdam
      • Department of Public Health (MGZ)
      Rotterdam, South Holland, Netherlands
  • 2005
    • Erasmus MC
      Rotterdam, South Holland, Netherlands
    • University of Oslo
      • Department of Nutrition
      Oslo, Oslo, Norway