This research focuses on designing effective interventions to promote physical activity (PA) among individuals experiencing cognitive difficulties alongside symptoms of depression or anxiety. The prevalence of both cognitive decline and mental health issues is increasing, highlighting the need for integrated approaches to improve well-being. Existing literature suggests a strong link between PA and improved cognitive function and mental health, but translating this knowledge into successful interventions remains challenging. This supplementary material contributes to this effort by systematically reviewing established change techniques from relevant interventions and categorizing them according to their mechanisms of action. The aim is to provide a comprehensive resource for researchers and practitioners designing PA interventions for this specific population. Understanding the interplay between change techniques and MoAs is crucial for developing targeted and effective interventions, maximizing adherence and achieving positive outcomes. This model addresses the complexity of this population by considering both cognitive and emotional factors, providing a more holistic approach compared to interventions focused solely on one aspect. The improved understanding of effective techniques promises to lead to more impactful interventions that contribute significantly to improved health and quality of life for this vulnerable population.

The supplementary material draws upon a substantial body of existing research on PA interventions for individuals with depression, anxiety, or cognitive impairment. It integrates findings from various sources, including randomized controlled trials (RCTs), systematic reviews, and intervention reports, to identify effective change techniques. These sources span different age groups and types of PA, providing a broad perspective on successful strategies. The review considers interventions employing diverse theoretical frameworks, such as the transtheoretical model of change (TTM), motivational interviewing (MI), and self-determination theory (SDT), recognizing that different theoretical lenses offer unique insights into behavior change. This comprehensive approach ensures that the identified change techniques are evidence-based and suitable for application in diverse contexts and with varying participant characteristics. The emphasis is placed on interventions demonstrating efficacy in improving PA levels and addressing the co-occurring cognitive and emotional challenges faced by the target population. The review acknowledges the limitations of existing studies, such as variations in methodology and sample sizes, but focuses on extracting consistent and robust findings applicable to the development of new interventions.

The methodology employed involves a systematic review of existing literature on PA interventions for populations experiencing cognitive concerns and symptoms of depression or anxiety. The researchers used the Theory and Techniques Tool (TaTT) to categorize and analyze the identified change techniques and mechanisms of action (MoAs). The TaTT is a structured framework that allows for a detailed breakdown of intervention components and their underlying theoretical principles. The search strategy likely included databases such as PubMed, PsycINFO, and other relevant databases to identify studies meeting inclusion criteria (e.g., RCTs, specific populations, PA interventions). The studies were reviewed to extract data on the types of PA promoted (aerobic, strength, balance, mixed), theoretical frameworks guiding the interventions, the specific change techniques employed, and the MoAs presumed to be involved. Inclusion criteria likely specified study designs, participant characteristics, and the presence of reported change techniques and MoAs. Exclusion criteria may have included studies lacking sufficient detail regarding intervention components or those focusing on populations significantly different from the target group. The extracted data was then systematically organized using the TaTT framework, allowing for a comprehensive comparison of interventions and identification of common themes. The focus was on analyzing the relationship between change techniques and their associated MoAs to enhance understanding of how interventions produce their effects. This process facilitates the development of a robust model for intervention design.

The key findings are presented in a table format, summarizing the change techniques and MoAs identified in the reviewed interventions. The table shows a wide array of techniques employed, including credible sources of information, instructions on performing exercises, goal setting (both behavior- and outcome-focused), graded tasks, action planning, self-monitoring, feedback (on behavior and outcomes), biofeedback, social support (emotional, practical, unspecified), social comparison, problem-solving, restructuring the social and physical environment, removing aversive stimuli, and various cognitive techniques (e.g., pros and cons analysis, framing/reframing, addressing incompatible beliefs). Many MoAs were identified across the interventions, including influences on general attitudes and beliefs, attitude towards the behavior, knowledge, skills, beliefs about capabilities, motivation, feedback processes, social influences, and environmental context and resources. Some interventions explicitly used theoretical models like TTM, MI, or SDT to guide the selection and implementation of change techniques. The table also highlights variations in types of PA utilized and the theoretical basis of each intervention. This rich data offers valuable insights into the diverse approaches that have shown promise in improving PA in individuals with cognitive concerns and symptoms of depression or anxiety. The variability in approaches suggests a need for tailoring interventions to individual needs and preferences while focusing on the most impactful change techniques and MoAs.

The findings demonstrate that a broad range of change techniques can be effective in promoting PA among people with cognitive concerns and symptoms of depression or anxiety. The detailed analysis of MoAs reveals the multiple pathways through which these techniques work to increase PA engagement and adherence. The systematic approach, using the TaTT framework, enables a more nuanced understanding of how different interventions achieve similar or different outcomes. The identified change techniques provide a valuable toolkit for designing new interventions that target specific barriers and facilitators to PA engagement. The variations in the types of PA employed (aerobic, strength, mixed) and theoretical models underpinning interventions suggest that a 'one-size-fits-all' approach is not optimal. Future interventions should consider personalized strategies that cater to individuals' preferences, capabilities, and specific needs. The results support the development of more integrated interventions that address both the cognitive and emotional aspects of the target population's condition. The rich data provided in this supplementary material can guide the development of future research, focusing on testing the efficacy of specific combinations of techniques and tailoring interventions to specific subgroups within this diverse population.

This supplementary material provides a valuable resource for designing effective PA interventions for individuals with cognitive concerns and symptoms of depression or anxiety. The systematic review and categorization of change techniques and MoAs offer a robust framework for creating tailored and impactful interventions. Future research should focus on testing specific combinations of these techniques and investigating their effectiveness in different subgroups within the target population. Longitudinal studies investigating long-term effects are also needed to further enhance our understanding and optimize interventions for this vulnerable group.

The review is limited by the availability and quality of existing literature. There may be publication bias towards studies reporting positive results. The diversity of interventions reviewed, including differences in participant characteristics, PA types, and intervention durations, limits the strength of direct comparisons. Furthermore, while the TaTT framework provides a structured approach, subjective interpretations in classifying change techniques and MoAs may still exist. Generalizability of findings to diverse populations and settings may be limited without further research.