Daniela Lange

Self-regulation prompts can increase fruit consumption : A one-hour randomised controlled online trial

Objective : The purpose was to examine whether a 1-h intervention would help increase fruit consumption in motivated individuals and to study the role of self-regulatory mechanisms in the behaviour change process, with a particular focus on dietary planning and action control. Methods : A randomised controlled trial compared a 1-h online intervention with controls in 791 participants. Dependent variables were fruit intake, planning to consume and dietary action control. Results : Experimental condition by time interactions documented superior treatment effects for the self-regulation group, although all participants benefited from the study. To identify the contribution of the intervention ingredients, multiple mediation analyses were conducted that yielded mediator effects for dietary action control and planning. Conclusions : A very brief self-regulatory nutrition intervention was superior to a control condition. Dietary planning and action control seem to play a major role in the mechanisms that facilitate fruit intake.

Preparing for Physical Activity: Pedometer Acquisition as a Self-regulatory Strategy

When people intend and plan to perform higher levels of physical activity, they do not start on impulse without preparing. Thus, preparation is a behavioral construct positioned between planning and target behavior. This may be reflected by the acquisition of sports equipment as well as monitoring devices such as pedometers. The research questions are who takes such preparatory action, whether picking up a complimentary pedometer can be predicted by self-efficacy and outcome expectancies, and whether this kind of preparatory action facilitates subsequent physical activity. A longitudinal physical activity survey was conducted with 143 university students who were offered a complimentary pedometer. Collecting this free gift served as indicator of preparatory behavior. Outcome expectancies and self-efficacy beliefs were specified as predictors of this behavior. Two weeks later, physical activity differences between the groups were determined. Collecting the pedometer was associated with higher levels of physical activity at follow-up. Outcome expectancies failed to predict the pedometer collection, but self-efficacy did. An interaction between these two factors indicated that self-efficacy compensated for low outcome expectancies. Pedometer acquisition signifies a preparatory action that is facilitated by self-efficacy. Positioned between planning and target behavior, they constitute a proximal self-regulatory step towards health behavior change.

Self-efficacy, planning, and preparatory behaviours as joint predictors of physical activity: A conditional process analysis

Objective: Planning can bridge the gap between intentions and action, but what bridges the gap between planning and action? This study helps to answer the question by disentangling the interrelationships between self-efficacy, planning and preparatory behaviours in predicting physical activity. Preparatory behaviours are tested as a working mechanism of planning. Moreover, it is tested whether the utility of preparatory behaviours depends on an individual’s level of self-efficacy. Methods: A survey assessed planning, self-efficacy and preparatory behaviours for physical activity. Adults (N = 166) provided data at two measurement points. In a longitudinal model, preparatory behaviours were specified as a mediator between planning and physical activity. Self-efficacy was specified as a possible moderator at two points in the model. Results: Preparatory behaviours mediated the relationship between planning and physical activity. An interaction between self-efficacy and preparatory behaviours on physical activity was found, indicating that individuals with low self-efficacy beliefs were more active if they engaged more frequently in preparatory behaviours. Conclusion: Planning seems to stimulate preparatory behaviours, which in turn make future physical activity more likely. Furthermore, as performing preparatory behaviours represent a step forward towards the enactment of behavioural goals, preparatory behaviours may be particular beneficial for individuals afflicted by self-doubts regarding physical activity.

A dietary planning intervention increases fruit consumption in Iranian women

The study examined whether a dietary planning intervention would help increase fruit consumption among Iranian women focusing on self-regulatory mechanisms in behavior change. We conducted a randomized controlled trial to compare a planning intervention with a control condition in 165 Iranian women (aged 17-48years). Dependent variable was fruit intake, and dietary planning served as the mediator. After baseline assessment (T1) the intervention group received a leaflet on fruit consumption with a planning sheet. Changes were assessed at 3-weeks (T2) and at 3-months follow-ups (T3). Findings showed that the dietary planning intervention led to an increase in fruit intake. Age moderated this mediation. Changes in dietary planning mediated between intervention and fruit consumption in middle aged women. Dietary planning seems to play a role in the mechanism that facilitates fruit intake among Iranian women. This mediation by planning was found in middle aged women (30-48 years old), but not in young adult women (17-29 years old).

The interplay of intention, autonomy, and sex with dietary planning: A conditional process model to predict fruit and vegetable intake

OBJECTIVES Dietary intentions are supposed to engender planning processes, which in turn stimulate dietary behaviour change. However, some studies failed to find such mediation effects, which suggest more complex and not yet unravelled relationships between these factors. One explanation may be that mediation works better under certain circumstances or only for specific subgroups. This study addresses this reasoning by examining autonomy beliefs and sex as putative moderators of the hypothesized mediation chain. DESIGN AND METHODS In a longitudinal design with three measurement points in time (1 week and 1 month apart), 912 women and 214 men were surveyed. Planning, intention, dietary autonomy beliefs, and sex were used to predict fruit and vegetable intake within a conditional process model designed to identify mechanisms of change. RESULTS The intention-planning-behaviour chain was qualified by a triple interaction involving autonomy beliefs and sex as moderators between intention and planning. Higher dietary autonomy resulted in higher levels of planning fruit and vegetable intake. For men, even in case of higher intention, at least medium levels of autonomy beliefs were necessary to facilitate planning processes. For women, already lower levels of autonomy beliefs can engender postintentional planning strategies and seem to even compensate lower intention. CONCLUSIONS Intention and planning are key predictors of dietary change. However, these variables work better under specific conditions (with a sufficient level of autonomy), and differently in subgroups (men vs. women). These results may explain the inconsistent findings of previous studies on the mediating effect of planning and allow for a better description of the mechanisms by which intentions may influence behaviour. Statement of contribution What is already known on this subject? The adoption of health-enhancing dietary behaviours can be facilitated by intentions and planning. Planning to eat more fruit and vegetable helps to translate intentions into actual consumption. Fruit and vegetable intake levels are higher in women than in men. What does this study add? Dietary intentions engender more likely planning processes when perceived autonomy concerning food consumption is high. Dietary autonomy beliefs and sex moderate the intention-planning-behaviour chain. Among men, dietary planning is highest when both intentions and autonomy are high.

Intervention Engagement Moderates the Dose–Response Relationships in a Dietary Intervention

Behavioral interventions could lead to changes in behavior through changes in a mediator. This dose–response relationship might only hold true for those participants who are actively engaged in interventions. This Internet study investigated the role of engagement in a planning intervention to promote fruit and vegetable consumption in addition to testing the intervention effect on planning and behavior. A sample of 701 adults (mean = 38.71 years, 81% women) were randomly assigned either to a planning intervention (experimental group) or to one of 2 control conditions (untreated waiting list control group or placebo active control group). Moderated mediation analyses were carried out. Significant changes over time and time × group effects revealed the effectiveness of the intervention. The effect of the intervention (time 1) on changes in behavior (time 3; 1 month after the personal deadline study participants set for themselves to start implementing their plans) was mediated by changes in planning (time 2; 1 week the personal deadline). Effects of planning on behavior were documented only at a moderate level of intervention engagement. This indicates an inverse U-shaped dose–response effect. Thus, examining participants’ intervention engagement allows for a more careful evaluation of why some interventions work and others do not.

Fruit and Vegetable Intake: the Interplay of Planning, Social Support, and Sex

PurposeIntention and planning are important predictors of dietary change. However, little attention has been given yet to the relationship between them as a function of other social-cognitive factors and their interplay with socio-demographics such as sex.MethodsIn an observational study (1520 women, 430 men) with two measurement points in time, intention (predictor), planning (mediator), social support (first moderator), and sex (second moderator) were assessed to predict changes in diet separately for fruit and vegetable intake.ResultsAll predictors had a main effect on fruit intake but no interactions emerged. For vegetable intake, the mediation-chain was qualified by a three-way interaction: for women, the lower the perceived social support, the more the translation of planning into behavior; for men, the higher the perceived social support, the more the translation of planning into behavior.ConclusionsEven though intention and planning are predictors of dietary change, they operate differently under specific conditions (level of social support), for specific subgroups (men vs. women), and for different target behaviors (fruit vs. vegetable intake). These results suggest to further examine the mechanisms by which intentions are translated into behavior via planning.

Sex differential mediation effects of planning within the health behavior change process

OBJECTIVE Previous research demonstrates that planning mediates the relationship between intention and health behavior change, but evidence is inconclusive, and possible sex differences within the intention-planning-behavior-chain are understudied so far. The current study, therefore, aims to disentangle this by addressing potential sex differences in the mediating role of planning in the health behavior change process. METHOD Three longitudinal studies were conducted in Germany between 2009 and 2011 (Study 1: 245 women, 216 men; Study 2: 156 women, 37 men; Study 3: 82 women, 84 men). In each study, intention (predictor), planning (mediator), and sex (moderator) were assessed to predict changes in (1) fruit and vegetable intake, (2) physical activity, and (3) sun protection. A moderated mediation model was specified to test whether the conditional direct effect of intention on health behavior change and/or the conditional indirect effect of intention on health behavior change through planning was different for men and women. RESULTS Similar patterns of sex differential effects emerged within the intention-planning-behavior-chain across all three studies. The conditional indirect effect of intention on health behavior change through planning was meaningful for men but not for women for all three health behaviors. Thus, planning acted as a mediator between intention and health behavior change only for men. CONCLUSION The study contributes to the understanding of the inconclusive evidence on the role of planning as mediator between intention and health behavior change and sheds some light of possible sex differences that qualify this mediation. The findings suggest that women and men may not similarly benefit from health behavior change modification techniques involving planning strategies. Future theoretical developments and interventions should take this into account.