David McMinn

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.

A bidirectional relationship between physical activity and executive function in older adults

Physically active lifestyles contribute to better executive function. However, it is unclear whether high levels of executive function lead people to be more active. This study uses a large sample and multi-wave data to identify whether a reciprocal association exists between physical activity and executive function. Participants were 4555 older adults tracked across four waves of the English Longitudinal Study of Aging. In each wave executive function was assessed using a verbal fluency test and a letter cancelation task and participants reported their physical activity levels. Fixed effects regressions showed that changes in executive function corresponded with changes in physical activity. In longitudinal multilevel models low levels of physical activity led to subsequent declines in executive function. Importantly, poor executive function predicted reductions in physical activity over time. This association was found to be over 50% larger in magnitude than the contribution of physical activity to changes in executive function. This is the first study to identify evidence for a robust bidirectional link between executive function and physical activity in a large sample of older adults tracked over time.

Validity of the New Lifestyles NL-1000 Accelerometer for Measuring Time Spent in Moderate-to-Vigorous Physical Activity in School Settings

Current interest in promoting physical activity in the school environment necessitates an inexpensive, accurate method of measuring physical activity in such settings. Additionally, it is recognized that physical activity must be of at least moderate intensity in order to yield substantial health benefits. The purpose of the study, therefore, was to determine the validity of the New Lifestyles NL-1000 (New Lifestyles, Inc., Lees Summit, Missouri, USA) accelerometer for measuring moderate-to-vigorous physical activity in school settings, using the Actigraph GT1M (ActiGraph, Pensacola, Florida, USA) as the criterion. Data were collected during a cross-country run (n = 12), physical education (n = 18), and classroom-based physical activities (n = 42). Significant and meaningful intraclass correlations between methods were found, and NL-1000 estimates of moderate-to-vigorous physical activity were not meaningfully different from GT1M-estimated moderate-to-vigorous physical activity. The NL-1000 therefore shows promising validity evidence as an inexpensive, convenient method of measuring moderate-to-vigorous physical activity in school settings.

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.

A Bidirectional Relationship between Executive Function and Health Behavior: Evidence, Implications, and Future Directions.

Physically active lifestyles and other health-enhancing behaviors play an important role in preserving executive function into old age. Conversely, emerging research suggests that executive functions facilitate participation in a broad range of healthy behaviors including physical activity and reduced fatty food, tobacco, and alcohol consumption. They do this by supporting the volition, planning, performance monitoring, and inhibition necessary to enact intentions and override urges to engage in health damaging behavior. Here, we focus firstly on evidence suggesting that health-enhancing behaviors can induce improvements in executive function. We then switch our focus to findings linking executive function to the consistent performance of health-promoting behaviors and the avoidance of health risk behaviors. We suggest that executive function, health behavior, and disease processes are interdependent. In particular, we argue that a positive feedback loop may exist whereby health behavior-induced changes in executive function foster subsequent health-enhancing behaviors, which in turn help sustain efficient executive functions and good health. We conclude by outlining the implications of this reciprocal relationship for intervention strategies, the design of research studies, and the study of healthy aging.

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.

Does real time variability in inhibitory control drive snacking behavior? An intensive longitudinal study.

Objective: Laboratory eating studies and cross-sectional surveys indicate individuals with inefficient executive function (EF) consume more unhealthy snacks than others. However, the importance of EF in determining snacking behavior in the “real world” has not been established. Contemporary behavioral and self-control theories posit EF as a dynamic resource fluctuating over time. Consequently, a test of the relevance of EF to behavior within individuals is required. This study tested within- and between-person effects of real-time variability in objectively measured inhibitory control (a core facet of EF) on subsequent snacking behavior in daily life. Method: A community sample of 64 adults recorded snacking behavior and completed a short Go/No-Go test (assessing inhibitory control) hourly over 7 consecutive days, yielding a total well-powered sample of 6,284 data-points. Generalized linear mixed models using lagged effects examined within-person and between-person effects of inhibitory control efficiency on snacking behavior. Results: When Go/No-Go test responses were 100 ms slower than the person-mean (indicating periods of poorer inhibitory control), snack consumption in the following hour was 25.67% higher, Exp (&ggr;) = 1.26, p = .002, 95% confidence interval (CI) [1.06, 1.49]. Between-individuals, person-mean reaction time (RT) did not predict snack consumption, Exp (&ggr;) = 1.02, p = .965, 95% CI [0.71, 1.46]. Conclusions: RT variability in inhibitory control efficiency is highly relevant to snacking behavior within individuals. Inhibitory control is an important driver of snacking in everyday life and an important target for interventions.

Evaluation of the trackstick (TM) super GPS tracker for use in walking research

Low levels of physical activity and an associated rise in obesity prevalence in adults and children are causes for concern (Lobstein, Baur, & Uauy, 2004). One approach to increasing daily physical activity levels is through active commuting to work or school. Interventions to increase active modes to and from the workplace or school include Walk in to Work Out (Mutrie et al., 2002) and Australia’s Walk to Work Day (Merom, Miller, Lymer, & Bauman, 2005), Traveling Green (McKee, Mutrie, Crawford, & Green, 2007), and the Walking Bus (Kearns, Collins, & Neuwelt, 2003). The recent interest in promoting active commuting necessitates an accurate and feasible method to measure ambulatory physical activity and track routes, for sound evaluation of these interventions. Previous studies used basic measures such as “hands up” surveys, travel diaries, questionnaires, and physical activity recall (Boarnet, Anderson, Day, McMillan, & Alfonzo, 2005). However, these measures are susceptible to social desirability and may result in misreported activity levels (Corder, Ekelund, Steele, Wareham, & Brage, 2008). Other more objective measures of commuting behavior include pedometers, accelerometers, and Geographic Information Systems-derived shortest routes (e.g., from home to school; Michaud-Thomson, Davidson, & Cuddihy, 2003; Sirard, Riner, McIver, & Pate, 2005; Timperio et al., 2006). None of these measures provides accurate information on distance walked and route taken. Due to children’s erratic travel habits, this information is particularly important when studying their trips to and from school. Children may deviate from the most direct route to play in a park or accompany a friend home, especially as the route home has a more flexible deadline for time of arrival. Additionally, children move in more lateral directions when unaccompanied than when traveling with an adult (Mackett, Brown, Gong, Kitazawa, & Paskins, 2007). Recent developments in physical activity monitoring have led to the use of global positioning systems (GPS), which captures movements in a way that other methods cannot.

Does pride really come before a fall? Longitudinal analysis of older English adults

Abstract Objective To test whether high levels of reported pride are associated with subsequent falls. Design Secondary analysis of the English Longitudinal Study of Ageing (ELSA) dataset. Setting Multi-wave longitudinal sample of non-institutionalised older English adults. Participants ELSA cohort of 6415 participants at wave 5 (baseline, 2010/11), of whom 4964 were available for follow-up at wave 7 (follow-up, 2014/15). Main outcome measures Self reported pride at baseline (low/moderate/high) and whether the participant had reported having fallen during the two years before follow-up. Results The findings did not support the contention that “pride comes before a fall.” Unadjusted estimates indicate that the odds of reported falls were significantly lower for people with high pride levels compared with those who had low pride (odds ratio 0.69, 95% confidence interval 0.58 to 0.81, P<0.001). This association remained after adjustment for age, sex, household wealth, and history of falls (odds ratio 0.81, 0.68 to 0.97, P<0.05). It was partially attenuated after further adjustment for mobility problems, eyesight problems, the presence of a limiting long term illness, a diagnosis of arthritis or osteoporosis, medication use, cognitive function, and pain and depression (odds ratio 0.86, 0.72 to 1.03, P<0.1). Because the confidence interval exceeded 1 in the final model, it remains possible that pride may not be an independent predictor of falls when known risk factors are considered. People with moderate pride did not have lower odds of having fallen than those with low pride in adjusted models. Participants lost to follow-up did not differ from those retained in terms of key variables, and weighting the analyses to account for selective attrition did not produce different results. Conclusions Contrary to the well known saying “pride comes before a fall,” these findings suggest that pride may actually be a protective factor against falling in older adults. Future studies may seek to investigate the mechanisms underpinning this relation.

The SNAPSHOT study protocol: SNAcking, Physical activity, Self-regulation, and Heart rate Over Time.

BackgroundThe cognitive processes responsible for effortful behavioural regulation are known as the executive functions, and are implicated in several factors associated with behaviour control, including focussing on tasks, resisting temptations, planning future actions, and inhibiting prepotent responses. Similar to muscles, the executive functions become fatigued following intensive use (e.g. stressful situations, when tired or busy, and when regulating behaviour such as quitting smoking). Therefore, an individual may be more susceptible to engaging in unhealthy behaviours when their executive functions are depleted. In the present study we investigate associations between the executive functions, snack food consumption, and sedentary behaviour in real time. We hypothesise that individuals may be more susceptible to unhealthy snacking and sedentary behaviours during periods when their executive functions are depleted. We test this hypothesis using real-time objective within-person measurements.Methods/DesignA sample of approximately 50 Scottish adults from varied socio-economic, working, and cultural backgrounds will participate in the three phases of the SNAcking, Physical activity, Self-regulation, and Heart rate Over Time (SNAPSHOT) study. Phase one will require participants to complete home-based questionnaires concerned with diet, eating behaviour, and physical activity (≈1.5 hours to complete). Phase two will constitute a 2-3 hour psychological laboratory testing session during which trait-level executive function, general intelligence, and diet and physical activity intentions, past behaviour, and automaticity will be measured. The final phase will involve a 7-day ambulatory protocol during which objective repeated assessments of executive function, snacking behaviour, physical activity, mood, heart rate, perceived energy level, current context and location will be measured during participants’ daily routines. Multi-level regression analysis, accounting for observations nested within participants, will be used to investigate associations between fluctuations in the executive functions and health behaviours.DiscussionData from the SNAPSHOT study will provide ecologically valid information to help better understand the temporal associations between self-regulatory resources (executive functions) and deleterious health behaviours such as snacking and sedentary behaviour. If we can identify particular periods of the day or locations where self-regulatory resources become depleted and produce suboptimal health behaviour, then interventions can be designed and targeted accordingly.