Visualisation and network analysis of physical activity and its determinants: Demonstrating opportunities in analysing baseline associations in the Let's Move It trial

Psychological network analysis of the relations between beliefs about smoking for smokers with and without a recent quit attempt

OBJECTIVE

Psychological network analysis was used to evaluate the relations between beliefs about cigarette smoking in current smokers with and without a recent quit attempt and determine if these networks differed in global strength (how strongly beliefs are related) or global structure (which beliefs are related).

DESIGN

Using two publicly available datasets, the California Smokers' Cohort (CSC; N = 933) and Wave 1 of the Population Assessment of Tobacco and Health (PATH; N = 7855), we evaluated differences in global strength and global structure of the beliefs held by current smokers with and without a recent quit attempt.

MAIN OUTCOME MEASURES

Strength and structure of networks generated for current smokers with and without a recent quit attempt.

RESULTS

In the CSC dataset there were differences between smokers with and without a recent quit attempt in global structure and marginal differences in global strength; the PATH dataset suggested small differences in global strength and structure.

CONCLUSION

The present study suggests that consideration of relations among smoking beliefs may be a valuable contribution to characterizing smoking beliefs when assessing smoking quit attempts.

How does a school-based intervention impact students' social cognitions on reducing sedentary behavior over 14 months?

Despite sedentary behavior being ubiquitous in students and detrimental to health, interventions specifically targeting it are mostly restricted to leisure time screen time reduction. With six weekly sessions alongside a poster campaign and an additional teacher intervention, the Let's Move It trial delivered environmental and psychological strategies to increase physical activity (PA) and reduce sedentary behavior (SB) in vocational schools, an understudied environment for behavioral interventions. Participants in the intervention arm considerably reduced sedentary time post-intervention. To investigate how social cognitions about restricting SB, as defined by the Reasoned Action Approach, change in intervention and control arms, self-reported data on social cognitions was collected as part of a cluster-randomized controlled trial from 1166 students (59% female, mage = 18.7 years, range: 16-49) in six vocational schools before, post-intervention, and 14 months post-baseline. Data were analyzed using mixed between-within repeated measures ANOVA. We found greater improvements in intention (F(1, 833) = 9.69; η2p = 0.01; p = .018) and descriptive norms (F(1, 831) = 13.25; η2p = 0.016; p < .001) in the intervention than control arm, but these effects depended on the included control variables. Generally, intervention effects leveled off from post-intervention to follow-up. The Let's Move It intervention for SB reduction showed modest, short-lived effects on social cognitions, indicating that changes in behavior are likely due to other factors like changes to the classroom environment. Optimally, SB reduction interventions should not only change behavior but produce robust changes in conscious intentions to restrict one's sitting, so that positive effects generalize to other contexts.

Interventions to prevent obesity in children aged 12 to 18 years old

BACKGROUND

Prevention of obesity in adolescents is an international public health priority. The prevalence of overweight and obesity is over 25% in North and South America, Australia, most of Europe, and the Gulf region. Interventions that aim to prevent obesity involve strategies that promote healthy diets or 'activity' levels (physical activity, sedentary behaviour and/or sleep) or both, and work by reducing energy intake and/or increasing energy expenditure, respectively. There is uncertainty over which approaches are more effective, and numerous new studies have been published over the last five years since the previous version of this Cochrane Review.

OBJECTIVES

To assess the effects of interventions that aim to prevent obesity in adolescents by modifying dietary intake or 'activity' levels, or a combination of both, on changes in BMI, zBMI score and serious adverse events.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was February 2023.

SELECTION CRITERIA

Randomised controlled trials in adolescents (mean age 12 years and above but less than 19 years), comparing diet or 'activity' interventions (or both) to prevent obesity with no intervention, usual care, or with another eligible intervention, in any setting. Studies had to measure outcomes at a minimum of 12 weeks post baseline. We excluded interventions designed primarily to improve sporting performance.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our outcomes were BMI, zBMI score and serious adverse events, assessed at short- (12 weeks to < 9 months from baseline), medium- (9 months to < 15 months) and long-term (≥ 15 months) follow-up. We used GRADE to assess the certainty of the evidence for each outcome.

MAIN RESULTS

This review includes 74 studies (83,407 participants); 54 studies (46,358 participants) were included in meta-analyses. Sixty studies were based in high-income countries. The main setting for intervention delivery was schools (57 studies), followed by home (nine studies), the community (five studies) and a primary care setting (three studies). Fifty-one interventions were implemented for less than nine months; the shortest was conducted over one visit and the longest over 28 months. Sixty-two studies declared non-industry funding; five were funded in part by industry. Dietary interventions versus control The evidence is very uncertain about the effects of dietary interventions on body mass index (BMI) at short-term follow-up (mean difference (MD) -0.18, 95% confidence interval (CI) -0.41 to 0.06; 3 studies, 605 participants), medium-term follow-up (MD -0.65, 95% CI -1.18 to -0.11; 3 studies, 900 participants), and standardised BMI (zBMI) at long-term follow-up (MD -0.14, 95% CI -0.38 to 0.10; 2 studies, 1089 participants); all very low-certainty evidence. Compared with control, dietary interventions may have little to no effect on BMI at long-term follow-up (MD -0.30, 95% CI -1.67 to 1.07; 1 study, 44 participants); zBMI at short-term (MD -0.06, 95% CI -0.12 to 0.01; 5 studies, 3154 participants); and zBMI at medium-term (MD 0.02, 95% CI -0.17 to 0.21; 1 study, 112 participants) follow-up; all low-certainty evidence. Dietary interventions may have little to no effect on serious adverse events (two studies, 377 participants; low-certainty evidence). Activity interventions versus control Compared with control, activity interventions do not reduce BMI at short-term follow-up (MD -0.64, 95% CI -1.86 to 0.58; 6 studies, 1780 participants; low-certainty evidence) and probably do not reduce zBMI at medium- (MD 0, 95% CI -0.04 to 0.05; 6 studies, 5335 participants) or long-term (MD -0.05, 95% CI -0.12 to 0.02; 1 study, 985 participants) follow-up; both moderate-certainty evidence. Activity interventions do not reduce zBMI at short-term follow-up (MD 0.02, 95% CI -0.01 to 0.05; 7 studies, 4718 participants; high-certainty evidence), but may reduce BMI slightly at medium-term (MD -0.32, 95% CI -0.53 to -0.11; 3 studies, 2143 participants) and long-term (MD -0.28, 95% CI -0.51 to -0.05; 1 study, 985 participants) follow-up; both low-certainty evidence. Seven studies (5428 participants; low-certainty evidence) reported data on serious adverse events: two reported injuries relating to the exercise component of the intervention and five reported no effect of intervention on reported serious adverse events. Dietary and activity interventions versus control Dietary and activity interventions, compared with control, do not reduce BMI at short-term follow-up (MD 0.03, 95% CI -0.07 to 0.13; 11 studies, 3429 participants; high-certainty evidence), and probably do not reduce BMI at medium-term (MD 0.01, 95% CI -0.09 to 0.11; 8 studies, 5612 participants; moderate-certainty evidence) or long-term (MD 0.06, 95% CI -0.04 to 0.16; 6 studies, 8736 participants; moderate-certainty evidence) follow-up. They may have little to no effect on zBMI in the short term, but the evidence is very uncertain (MD -0.09, 95% CI -0.2 to 0.02; 3 studies, 515 participants; very low-certainty evidence), and they may not reduce zBMI at medium-term (MD -0.05, 95% CI -0.1 to 0.01; 6 studies, 3511 participants; low-certainty evidence) or long-term (MD -0.02, 95% CI -0.05 to 0.01; 7 studies, 8430 participants; low-certainty evidence) follow-up. Four studies (2394 participants) reported data on serious adverse events (very low-certainty evidence): one reported an increase in weight concern in a few adolescents and three reported no effect.

AUTHORS' CONCLUSIONS

The evidence demonstrates that dietary interventions may have little to no effect on obesity in adolescents. There is low-certainty evidence that activity interventions may have a small beneficial effect on BMI at medium- and long-term follow-up. Diet plus activity interventions may result in little to no difference. Importantly, this updated review also suggests that interventions to prevent obesity in this age group may result in little to no difference in serious adverse effects. Limitations of the evidence include inconsistent results across studies, lack of methodological rigour in some studies and small sample sizes. Further research is justified to investigate the effects of diet and activity interventions to prevent childhood obesity in community settings, and in young people with disabilities, since very few ongoing studies are likely to address these. Further randomised trials to address the remaining uncertainty about the effects of diet, activity interventions, or both, to prevent childhood obesity in schools (ideally with zBMI as the measured outcome) would need to have larger samples.

Observational longitudinal association between waking movement behaviours and psychological distress among adolescents using isotemporal analysis: DADOS study

This study aimed to examine the impact of reallocating time spent in waking movement behaviours at baseline on indicators of psychological distress at 24-month follow-up using isotemporal substitution regression models among a sample of Spanish adolescents. The DADOS (Deporte, ADOlescencia y Salud) study is a 3-year longitudinal observational research project carried out between years 2015-2017. The analyses included 197 adolescents (91 girls) aged 13.9 ± 0.3 years at baseline. Waking movement behaviours were assessed by a wrist-worn GENEActiv triaxial accelerometer and expressed as minutes/day of light physical activity (LPA), moderate-vigorous physical activity (MVPA) and time spent in sedentary behaviour (SB). The Behaviour Assessment System for Children and Adolescents (level 3 for adolescents) was used to assess psychological distress indicators (i.e., anxiety, social stress, and risk of depression). Results showed significant associations only for girls. The substitution of 10 min/day of SB or LPA at baseline with 10 min/day of MVPA was associated with lower levels of anxiety (both p ≤ 0.01) and social stress (both p < 0.05) at follow-up. The substitution of 10 min/day of SB with 10 min/day of LPA was associated with higher levels of anxiety at follow-up (p = 0.01). These findings highlight the need of specific physical activity recommendations for mental health paying special attention to sex-differences.

A Network Analysis of Multiple Preconception Health Behaviors in Chinese Women

BACKGROUND

A healthy preconception lifestyle, consisting of multiple health behaviors, is crucial for preventing adverse health outcomes in mothers and offspring. Although knowledge about the pattern of inter-behavior relations may provide insights for nudging multiple health behavior changes, this has not been adequately explored in the existing literature. Adopting a network perspective, the present study conceptualized multiple health behaviors as a behavior network (i.e., behaviors as nodes, inter-behavior relations as edges) and utilized network analysis to investigate the pattern of interrelations of preconception health behaviors in a large sample of Chinese women.

METHOD

We used the data of a population-based cohort study in China to estimate the behavior network. An analytic sample included 41,127 Chinese women who were surveyed about their adoptions of multiple health behaviors during the preconception period.

RESULTS

Network analysis revealed a relatively dense behavior network and visualized the network structure of multiple preconception health behaviors. Subsequent centrality analysis identified three central behaviors (i.e., avoiding second- or third-hand smoke, reducing psychosocial stress, and reducing alcohol) that had distinctively stronger connections to other behaviors.

CONCLUSIONS

Preconception health behaviors were strongly interconnected, and certain behaviors had stronger influences than others within the behavior network. Our findings highlight the strong inter-relatedness of preconception health behaviors. This study also encourages targeting the three central behaviors in preconception lifestyle promotions because this may bring more secondary improvements on other non-targeted behaviors and thereby achieve comprehensive lifestyle change.

Uptake of planning as a self-regulation strategy: Adolescents' reasons for (not) planning physical activity in an intervention trial

OBJECTIVES

Planning is an effective self-regulation strategy. However, little is known why some people take up planning and some do not. Such understanding would help interventions to promote planning. We investigated how adolescents explain their (non) use of planning for physical activity after an intervention.

METHODS

Qualitative content analysis was employed to investigate follow-up interviews (a purposeful sampling; n = 19 low-to-moderately active, vocational school students) of Let's Move It trial participants twice post-intervention: 6-8 weeks and 14 months post-baseline. In the intervention, planning was one of the key techniques used to promote PA.

RESULTS

We identified seven categories linked to reasons for (not) using planning. Most were related to feelings anticipated to result from planning. Action- and identity-related concerns were also raised. The reasons for planning were that the plan (1) helps to clarify what to do and to get things done, (2) strengthens the feeling of autonomy, (3) promotes a sense of progress, ability and control over one's PA. The reasons for not planning were that (having) a plan may (1) feel forced and like an unpleasant duty, (2) take away life's spontaneity and freedom, (3) result in anticipated annoyance and bad mood if one fails to enact the plan, or (4) be an effective strategy for others but not for the interviewee.

CONCLUSIONS

Planning may not only link to behavioural control but also the sense of autonomy, and thus subsequent motivation. We suggest various strategies to promote planning, including challenging non-planner identity and harnessing social dimension of planning.

Studying Behaviour Change Mechanisms under Complexity

Understanding the mechanisms underlying the effects of behaviour change interventions is vital for accumulating valid scientific evidence, and useful to informing practice and policy-making across multiple domains. Traditional approaches to such evaluations have applied study designs and statistical models, which implicitly assume that change is linear, constant and caused by independent influences on behaviour (such as behaviour change techniques). This article illustrates limitations of these standard tools, and considers the benefits of adopting a complex adaptive systems approach to behaviour change research. It (1) outlines the complexity of behaviours and behaviour change interventions; (2) introduces readers to some key features of complex systems and how these relate to human behaviour change; and (3) provides suggestions for how researchers can better account for implications of complexity in analysing change mechanisms. We focus on three common features of complex systems (i.e., interconnectedness, non-ergodicity and non-linearity), and introduce Recurrence Analysis, a method for non-linear time series analysis which is able to quantify complex dynamics. The supplemental website provides exemplifying code and data for practical analysis applications. The complex adaptive systems approach can complement traditional investigations by opening up novel avenues for understanding and theorising about the dynamics of behaviour change.

Differences in Habitual Physical Activity Behavior between Students from Different Vocational Education Tracks and the Association with Cognitive Performance

Vocational education and training (VET) educates students for a broad range of occupations, which may be associated with differences in habitual physical activity behavior (PAB). Research suggests that physical activity (PA) is positively and sedentary behavior (SB) is negatively associated with cognitive performance. Therefore, we aimed to compare habitual PAB in VET students from different educational tracks and investigate its association with cognitive performance in a cross-sectional study. Students wore an ActivPAL accelerometer continuously for seven days to measure PAB. Cognitive performance was assessed with objective tests for inhibition, shifting, and updating. Hairdresser and Sports students sat significantly less than Administrative and Nursing students. Hairdresser students stood significantly more than other tracks. Admin students stood significantly less than Sports/Nursing students. Sports students moved significantly more than Hairdresser and Nursing students. Time in bed was significantly lowest in Nursing students. No significant associations between any PAB and cognitive performance were found. In general, Admin students showed the unhealthiest habitual PAB. Higher PA or lower SB neither improve nor decrease cognitive performance. Thus, future health interventions focusing on exchanging SB for PA at schools can facilitate a healthier lifestyle of VET students, especially in Admin students, without interfering with cognitive performance.

Thematic analysis of acceptability and fidelity of engagement for behaviour change interventions: The Let's Move It intervention interview study

OBJECTIVES

Intervention participants' responses to and engagement with interventions are a key intermediate step between interventions and intended outcomes. The aim of this study was to qualitatively investigate crucial aspects of engagement, namely acceptability (experienced cognitive and emotional responses to the intervention), receipt (comprehension of intervention content), and skill enactment (skill performance in target settings), within the Let's Move It, a multi-component school-based physical activity intervention.

DESIGN

A longitudinal qualitative study embedded in a cluster-randomized trial, with individual interviews of purposefully sampled intervention participants immediately post-intervention (n = 21) and at 14 months (n = 14).

METHODS

Semi-structured interviews were analysed using thematic analysis. Abductive coding process was taken to identify categories for themes.

RESULTS

The analysis resulted in 12 themes and 18 subthemes. Overall, participants reported perceived effectiveness of and affective attitude towards the intervention (acceptability) and understood the main messages and skills (receipt). For example, findings indicated comprehension of the non-judgemental nature and choice-providing messages of the intervention underpinned by self-determination theory. Despite reporting understanding how and why to perform the skills, not using them was a highlighted theme (skill enactment), particularly for self-regulatory techniques such as planning. Friends' role as key self-motivation technique was a prevalent theme. In the within-individual analysis, three different engager types were identified: positive, ambivalent, and negative.

CONCLUSION

Identifying misunderstandings and difficulties in skill acquisition can help interpret main trial outcomes and inform further intervention optimization. This study provides an example of how to use thematic analysis to assess acceptability, receipt, and enactment in interventions.

Modelling multiple health behavior change with network analyses: results from a one-year study conducted among overweight and obese adults

This study examined the between-person associations of seven health behaviors in adults with obesity participating in a weight loss intervention, as well as the covariations between these behaviors within-individuals across the intervention. The present study included data from a 12-month weight loss trial (N = 278). Seven health behaviors (physical activity, sedentary behavior, sleep duration, and consumption of fruits, vegetables, total fat and added sugar) were measured at baseline, 6- and 12-months. Between- and within-participants network analyses were conducted to examine how these behaviors were associated through the 12-month intervention and covaried across months. At the between-participants level, associations were found within the different diet behaviors and between total fat and sedentary behaviors. At the within-participants level, covariations were found between sedentary and diet behaviors, and within diet behaviors. Findings suggest that successful multiple health behaviors change interventions among adults with obesity will need to (1) simultaneously target sedentary and diet behaviors; and (2) prevent potential compensatory behaviors in the diet domain.