Exploring Perceived Changes to Mental Health When Restricting and Resuming Specific Adaptive Daily Actions: Longitudinal Qualitative Substudy Within a Randomized Controlled Trial.

Background: Anxiety and depressive disorders are common and burdensome, yet many people prefer to self-manage and do not access treatment or fail to achieve meaningful improvement. Prior research indicates that the frequency of performing simple, everyday actions, namely "The Things You Do" (TYD; ie, healthy thinking, meaningful activities, having goals and plans, healthy routines, and social connection), is strongly associated with support mental health and well-being. This research has been primarily quantitative in nature, and so less is known about how people perceive and interpret changes in their mental health when engaging in or limiting these actions. Objective: This study aims to explore participants' perceptions of mental health changes and associated insights into what most impacts their mental health, during a randomized controlled trial involving the systematic restriction and followed by the resumption of the TYD actions. Methods: This longitudinal qualitative substudy analyzed weekly free-text comments from 70 healthy Australian adults (intervention group [IG] n=36; control group [CG] n=34). IG participants completed an 8-week randomized controlled trial comprising 3 phases: a 2-week baseline phase (Phase A), a 2-week behavior restriction phase during which they reduced the frequency of the TYD actions (Phase B), and a 4-week recovery or resumption phase during which they increased the frequency of the TYD actions back to usual levels (Phase C). CG participants were instructed to maintain usual habits and activities. The weekly free-text comments were related to what participants had noticed and learned about their mental health. These were thematically analyzed using framework methods to identify patterns in perceived changes, considering trial phase, group allocation, and participant characteristics. Results: Analyses identified five interrelated themes around what participants reportedly learned and what most impacted their mental health: (1) rhythms of daily life and routine, (2) harnessing internal psychological resources, (3) social support and interpersonal stressors, (4) staying active and enjoying yourself, and (5) environmental and external influences. In the IG, participants reported that behavioral restriction led to subjective disruptions across all 5 themes, precipitating declines in mood, energy, and stability; resumption fostered recovery, along with increased insights into oneself and mental health, coping strategies, and a sense of agency. Compared to the IG, the CG more often emphasized environmental and external influences. Conclusions: The findings reinforce the centrality of specific daily actions, namely the TYD, to people's subjective well-being and suggest an additional "macro-level" comprising environmental and external influences. Exposure to behavioral restriction and resumption/recovery served to highlight the importance of certain factors for mental health and appeared to improve people's sense of agency and locus of control regarding their mental health.