According to the strength model, self-control is a finite resource that determines capacity for effortful control over dominant responses and, once expended, leads to impaired self-control task performance, known as ego depletion. A meta-analysis of 83 studies tested the effect of ego depletion on task performance and related outcomes, alternative explanations and moderators of the effect, and additional strength model hypotheses. Results revealed a significant effect of ego depletion on self-control task performance. Significant effect sizes were found for ego depletion on effort, perceived difficulty, negative affect, subjective fatigue, and blood glucose levels. Small, nonsignificant effects were found for positive affect and self-efficacy. Moderator analyses indicated minimal variation in the effect across sphere of depleting and dependent task, frequently used depleting and dependent tasks, presentation of tasks as single or separate experiments, type of dependent measure and control condition task, and source laboratory. The effect size was moderated by depleting task duration, task presentation by the same or different experimenters, intertask interim period, dependent task complexity, and use of dependent tasks in the choice and volition and cognitive spheres. Motivational incentives, training on self-control tasks, and glucose supplementation promoted better self-control in ego-depleted samples. Expecting further acts of self-control exacerbated the effect. Findings provide preliminary support for the ego-depletion effect and strength model hypotheses. Support for motivation and fatigue as alternative explanations for ego depletion indicate a need to integrate the strength model with other theories. Findings provide impetus for future investigation testing additional hypotheses and mechanisms of the ego-depletion effect.

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The aim of the present study was to examine relations between behavior, intentions, attitudes, subjective norms, perceived behavioral control, self-efficacy, and past behavior across studies using the Theories of Reasoned Action (TRA) and Planned Behavior (TPB) in a physical activity context. Meta-analytic techniques were used to correct the correlations between the TRA/TPB constructs for statistical artifacts across 72 studies, and path analyses were conducted to examine the pattern of relationships among the variables. Results demonstrated that the TRA and TPB both exhibited good fit with the corrected correlation matrices, but the TPB accounted for more variance in physical activity intentions and behavior. In addition, self-efficacy explained unique variance in intention, and the inclusion of past behavior in the model resulted in the attenuation of the intention-behavior, attitude-intention, self-efficacy-intention, and self-efficacy-behavior relationships. There was some evidence that the study relationships were moderated by attitude-intention strength and age, but there was a lack of homogeneity in the moderator groups. It was concluded that the major relationships of the TRA/TPB were supported in this quantitative integration of the physical activity literature, and the inclusion of self-efficacy and past behavior are important additions to the model.

Good self-control has been linked to adaptive outcomes such as better health, cohesive personal relationships, success in the workplace and at school, and less susceptibility to crime and addictions. In contrast, self-control failure is linked to maladaptive outcomes. Understanding the mechanisms by which self-control predicts behavior may assist in promoting better regulation and outcomes. A popular approach to understanding self-control is the strength or resource depletion model. Self-control is conceptualized as a limited resource that becomes depleted after a period of exertion resulting in self-control failure. The model has typically been tested using a sequential-task experimental paradigm, in which people completing an initial self-control task have reduced self-control capacity and poorer performance on a subsequent task, a state known as ego depletion Although a meta-analysis of ego-depletion experiments found a medium-sized effect, subsequent meta-analyses have questioned the size and existence of the effect and identified instances of possible bias. The analyses served as a catalyst for the current Registered Replication Report of the ego-depletion effect. Multiple laboratories (k = 23, total N = 2,141) conducted replications of a standardized ego-depletion protocol based on a sequential-task paradigm by Sripada et al. Meta-analysis of the studies revealed that the size of the ego-depletion effect was small with 95% confidence intervals (CIs) that encompassed zero (d = 0.04, 95% CI [-0.07, 0.15]. We discuss implications of the findings for the ego-depletion effect and the resource depletion model of self-control.

The trans-contextual model proposes that young people's perceived autonomy support in physical education will affect their perceived locus of causality, intentions, and physical activity behavior in leisure time. High school students completed measures of perceived autonomy support and perceived locus of causality in physical education. One week later, participants' perceived locus of causality and constructs from the theory of planned behavior were assessed in leisure time. Leisure-time physical activity behavior was measured 5 weeks later. Perceived autonomy support in physical education affected leisure-time physical activity directly and indirectly through a motivational sequence involving internal perceived locus of causality, attitudes, perceived behavioral control, and intentions. Results support the trans-contextual model indicating that perceived autonomy support in an educational context influences motivation in a leisure-time context.

Evidence from this synthesis supported the theoretical integration and proposed motivational sequence. Results are discussed with reference to the complementary aspects of the TPB and SDT and the need for integrated experimental or intervention studies on a broader range of health behaviours.

The purpose of this paper is to provide an overview of the literature on two planning intervention techniques in health behaviour research, implementation intentions and action planning, and to develop evidence-based recommendations for effective future interventions and highlight priority areas for future research. We focused our review on four key areas: (1) definition and conceptualisation; (2) format and measurement; (3) mechanisms and processes; and (4) design issues. Overall, evidence supports the effectiveness of planning interventions in health behaviour with advantages including low cost and response burden. There is, however, considerable heterogeneity in the effects across studies and relatively few registered randomised trials that include objective behavioural measures. Optimally-effective planning interventions should adopt 'if-then' plans, account for salient and relevant cues, include examples of cues, be guided rather than user-defined, and include boosters. Future studies should adopt randomised controlled designs, report study protocols, include fidelity checks and relevant comparison groups, and adopt long-term behavioural follow-up measures. Priority areas for future research include the identification of the moderators and mediators of planning intervention effects. Future research also needs to adopt 'best practice' components of planning interventions more consistently to elucidate the mechanisms and processes involved.

The trans-contextual model outlines the processes by which autonomous motivation toward activities in a physical education context predicts autonomous motivation toward physical activity outside of school, and beliefs about, intentions toward, and actual engagement in, out-of-school physical activity. In the present article, we clarify the fundamental propositions of the model and resolve some outstanding conceptual issues, including its generalizability across multiple educational domains, criteria for its rejection or failed replication, the role of belief-based antecedents of intentions, and the causal ordering of its constructs. We also evaluate the consistency of model relationships in previous tests of the model using path-analytic meta-analysis. The analysis supported model hypotheses but identified substantial heterogeneity in the hypothesized relationships across studies unattributed to sampling and measurement error. Based on our meta-analysis, future research needs to provide further replications of the model in diverse educational settings beyond physical education and test model hypotheses using experimental methods.