Understanding parental support for children's 24-hour movement behaviors based on an adapted HAPA framework: A three-wave prospective study.

Parental supportive behavior (PSB) plays a pivotal role in shaping children's 24-hour movement behaviors (24-HMB), including light physical activity (LPA), moderate-to-vigorous physical activity (MVPA), sedentary screen time (SST), and sleep. However, the psychosocial determinants and the changing process of PSB remain understudied. Using a three-wave prospective design over four months, this study examined the psychosocial mechanisms of PSB towards children's 24-HMB based on an adapted health action process approach (HAPA) framework among 812 parents (36.61 ± 3.80 years; 68.7% female). The adapted HAPA model demonstrated acceptable fit indices (CFI = .952-.980, TLI = .946-.967), incorporating the original HAPA model along with past behavior and affective attitude. The model explained 31.6%-54.8% of the variance in PSB across the four outcomes (LPA, MVPA, SST, and sleep). Motivational self-efficacy and outcome expectancy consistently predicted intentions, while intentions and action control emerged as stable predictors of PSB across all four outcomes. The prediction of planning, and volitional self-efficacy on PSB varied by movement behaviors. Both past behavior and positive affective attitude were directly associated with PSB, while their inclusion attenuated most pathways in the original HAPA model. Further, intention and action control served as prominent mediators between past behavior, affective attitude, and PSB across all outcomes. Future research could leverage the adapted HAPA framework to guide the development of parent-based interventions aimed at improving children's 24-HMB.