Norah M. Nelson

Active commuting to school: How far is too far?

BackgroundWalking and cycling to school provide a convenient opportunity to incorporate physical activity into an adolescents daily routine. School proximity to residential homes has been identified as an important determinant of active commuting among children. The purpose of this study is to identify if distance is a barrier to active commuting among adolescents, and if there is a criterion distance above which adolescents choose not to walk or cycle.MethodsData was collected in 2003–05 from a cross-sectional cohort of 15–17 yr old adolescents in 61 post primary schools in Ireland. Participants self-reported distance, mode of transport to school and barriers to active commuting. Trained researchers took physical measurements of height and weight. The relation between mode of transport, gender and population density was examined. Distance was entered into a bivariate logistic regression model to predict mode choice, controlling for gender, population density socio-economic status and school clusters.ResultsOf the 4013 adolescents who participated (48.1% female, mean age 16.02 ± 0.661), one third walked or cycled to school. A higher proportion of males than females commuted actively (41.0 vs. 33.8%, χ2 (1) = 22.21, p < 0.001, r = -0.074). Adolescents living in more densely populated areas had greater odds of active commuting than those in the most sparsely populated areas (χ2 (df = 3) = 839.64, p < 0.001). In each density category, active commuters travelled shorter distances to school. After controlling for gender and population density, a 1-mile increase in distance decreased the odds of active commuting by 71% (χ2 (df = 1) = 2591.86, p < 0.001). The majority of walkers lived within 1.5 miles and cyclists within 2.5 miles. Over 90% of adolescents who perceived distance as a barrier to active commuting lived further than 2.5 miles from school.ConclusionDistance is an important perceived barrier to active commuting and a predictor of mode choice among adolescents. Distances within 2.5 miles are achievable for adolescent walkers and cyclists. Alternative strategies for increasing physical activity are required for individuals living outside of this criterion.

Development of the Scottish Walkability Assessment Tool (SWAT)

The Scottish Walkability Assessment Tool (SWAT) was designed to objectively record aspects of the physical environment believed to be related to walking in urban Scotland. Reliability was assessed by three pairs of trained raters auditing 30 street segments on two occasions. Eighteen items were reliably audited and displayed adequate environmental variability, 25 items proved unreliable, and 69 items lacked adequate environmental variability. The large number of items that lacked environmental variability indicates a relatively uniform environment in terms of characteristics, which the literature indicates might be used to differentiate walkability; however, the 18 reliable items can potentially be used to differentiate walkability.

Obesogenic environments: Are neighbourhood environments that limit physical activity obesogenic?

The impact of obesogenic environments on adolescent health is poorly understood. This study examines if neighbourhood features related to physical activity are also related to unhealthy weight status. Adolescents (N=4587, age 15-17 years, 51.4% male) self-reported physical activity and neighbourhood perceptions. Trained researchers measured height and weight. Logistic regression identified if neighbourhood perceptions predicted overweight or obesity. Adolescents who reported convenient physical activity facilities were 2% less likely to be overweight/obese and 5% less likely to be obese, controlled for socio-demographic variables and clustering by school. Physical activity does not appear to directly influence or mediate the relationship between perceived convenient facilities and weight status.

Predicting active school travel : the role of planned behavior and habit strength

BackgroundDespite strong support for predictive validity of the theory of planned behavior (TPB) substantial variance in both intention and behavior is unaccounted for by the model’s predictors. The present study tested the extent to which habit strength augments the predictive validity of the TPB in relation to a currently under-researched behavior that has important health implications, namely children’s active school travel.MethodParticipants (N = 126 children aged 8–9 years; 59 % males) were sampled from five elementary schools in the west of Scotland and completed questionnaire measures of all TPB constructs in relation to walking to school and both walking and car/bus use habit. Over the subsequent week, commuting steps on school journeys were measured objectively using an accelerometer. Hierarchical multiple regressions were used to test the predictive utility of the TPB and habit strength in relation to both intention and subsequent behavior.ResultsThe TPB accounted for 41 % and 10 % of the variance in intention and objectively measured behavior, respectively. Together, walking habit and car/bus habit significantly increased the proportion of explained variance in both intention and behavior by 6 %. Perceived behavioral control and both walking and car/bus habit independently predicted intention. Intention and car/bus habit independently predicted behavior.ConclusionsThe TPB significantly predicts children’s active school travel. However, habit strength augments the predictive validity of the model. The results indicate that school travel is controlled by both intentional and habitual processes. In practice, interventions could usefully decrease the habitual use of motorized transport for travel to school and increase children’s intention to walk (via increases in perceived behavioral control and walking habit, and decreases in car/bus habit). Further research is needed to identify effective strategies for changing these antecedents of children’s active school travel.

Where is the Theoretical Basis for Understanding and Measuring the Environment for Physical Activity

Researchers are beginning to explore environmental correlates to further the field of physical activity research. Before interventions and experimental investigations can be undertaken, it is necessary to identify specific environmental features that are consistent correlates of physical activity. There has been a plethora of research measuring such cross-sectional associations since this field came to the fore in 2003. This paper posits that it is time for researchers to evaluate the state of knowledge, and suggests that future developments in this field focus on the theoretical bases for (i) measurement of the environment and (ii) understanding the links between perceptions of the environment and behaviour through psychological theories of cognition. Key theories considered include social ecology and the theory of planned behaviour. It is suggested that with a continued absence of a common conceptual framework, vocabulary and measurement tools the majority of studies may remain at a correlates stage. In highlighting issues with current methodologies, this commentary encourages more grounded theoretical approaches to the study of the environment and physical activity.

The effect of a school-based active commuting intervention on children's commuting physical activity and daily physical activity

OBJECTIVE To investigate the effect of a school-based intervention called Travelling Green (TG) on childrens walking to and from school and total daily physical activity. METHOD A quasi-experiment with 166 Scottish children (8-9 years) was conducted in 2009. One group (n=79) received TG and another group (n=87) acted as a comparison. The intervention lasted 6 weeks and consisted of educational lessons and goal-setting tasks. Steps and MVPA (daily, a.m. commute, p.m. commute, and total commute) were measured for 5 days pre- and post-intervention using accelerometers. RESULTS Mean steps (daily, a.m., p.m., and total commute) decreased from pre- to post-intervention in both groups (TG by 901, 49, 222, and 271 steps/day and comparison by 2528, 205, 120, and 325 steps/day, respectively). No significant group by time interactions were found for a.m., p.m., and total commuting steps. A medium (partial eta squared=0.09) and significant (p<0.05) group by time interaction was found for total daily steps. MVPA results were similar to step results. CONCLUSIONS TG has a little effect on walking to and from school. However, for total daily steps and daily MVPA, TG results in a smaller seasonal decrease than for children who do not receive the intervention.

The Take PART Study (Physical Activity Research for Teenagers): Rationale and Methods

BACKGROUND The Take PART study--Physical Activity Research for Teenagers--was undertaken to assess (1) physical activity and sedentary behaviors, (2) indices of health and fitness, and (3) to provide information, from a social ecological perspective, on the correlates of physical activity in a large sample of 15- to 17-year-old Irish adolescents. This manuscript outlines the rationale and methodology of the Take PART study. METHODS A sample of 4720 students (mean age=16.03 years+/-0.66, range 15 to 17 years; 49.5% female) participated. Fifty participants were assessed during each 3-hour school visit, with a ratio of 1 researcher to 10 students. Standardized testing procedures and extensive researcher training ensured that intertester and intratester reliability for all physical measures was >or=.85. The height, weight, waist circumference, hip circumference, blood pressure, and cardiorespiratory fitness protocols are explained. The questionnaire used well-known, valid, and reliable self-report measures. Where appropriate, additional psychometric testing was undertaken. CONCLUSIONS Take PART is a school-based study. Its methods are simple, easy to replicate, financially viable, and scientifically valid. Its unique dataset will allow the evaluation of a social ecological approach as a viable option for improving understanding of youth inactivity. Ultimately, this knowledge will assist in successful intervention design.

The Strathclyde Evaluation of Children's Active Travel (SE-CAT): study rationale and methods

BackgroundThe school commute is a prime opportunity to increase childrens physical activity levels. However, active commuting has decreased over the past 40 years. Strategies that increase walking to school are therefore needed. Travelling Green (TG) is a school-based active travel resource aimed at increasing childrens walking to school. The resource consists of a curriculum-based program of lessons and goal setting activities. A previous study found that children who received the TG intervention increased self-reported distance travelled to school by active modes and reduced the distance travelled by inactive modes. This study was limited by self-reported outcome measures, a small sample, and no follow-up measures. A more robust evaluation of TG is required to address these limitations. This paper describes the rationale and methods for such an evaluation of Travelling Green, and describes the piloting of various active commuting measures in primary school children.Methods/DesignMeasures of active commuting were piloted in a sample of 26 children (aged 8-9 years) over one school week. These measures were subsequently used in an 18-month quasi-experimental design to evaluate the effect of TG on commuting behaviour. Participants were 166 children (60% male) aged 8-9 years from 5 primary schools. Two schools (n = 79 children) received TG in September/October 2009. Three schools (n = 87 children) acted as a comparison group, and subsequently received TG at a later date. Physical activity was measured using Actigraph GT1M accelerometers. Personal and environmental determinants of active commuting were measured via parent and child questionnaires, as were factors related to the Theory of Planned Behaviour and the construct of habit. Measures were taken pre- and post-intervention and at 5 and 12 months follow-up.DiscussionThe piloted protocol was practical and feasible and piloted measures were reliable and valid. All study data, including 5 and 12 month follow-up, have been collected and processed. Data analysis is ongoing. Results will indicate whether TG successfully increases active commuting in a sample of Scottish school children and will inform future efforts in school active travel promotion.