Background: Gestational diabetes mellitus (GDM) is one of the most common medical disorders in pregnancy. Evidence has demonstrated that moderate-intensity physical activity may reduce the risk of gestational diabetes. However, women at risk of GDM spend most of their time performing sedentary behaviors. Although researchers identified self-efficacy as a mediator to overcome physical activity barriers, exercise intervention during pregnancy based on self-efficacy theory has not been discussed so far. Furthermore, there is conflicting evidence regarding the effects of a physical exercise intervention on the incidence of GDM and other maternal or neonatal outcomes in women at higher risk for GDM. Methods/design: A single-center, parallel, randomized controlled trial will be conducted in a maternal–child health care center. A total of 244 pregnant women at high risk for GDM will be randomized into a study group receiving a self-efficacy-enhancing physical activity intervention or a control group receiving the usual care. The intervention will consist of four group sessions and everyday reminders by WeChat (Tencent, Shenzhen, China). The program will begin at approximately 13–14⁺⁶ gestational weeks and end at 36⁺⁶ gestational weeks. The primary outcomes will include the incidence of GDM, blood sugar values, and physical activity. The secondary outcomes will include physical activity self-efficacy, gestational weight gain, maternal outcomes, and neonatal outcomes. Discussion: The findings of this research will contribute toward understanding the effects of a self-efficacy theory-oriented physical activity program on the incidence of GDM, blood sugar values, physical activity level, gestational weight gain, physical activity self-efficacy, maternal outcomes, and neonatal outcomes. Trial registration: Chinese Clinical Trial Registry (CHiCTR) ChiCTR2200056355. Registered on February 4, 2022.

Older adults who have undergone percutaneous coronary intervention (PCI) face a heightened risk of major adverse cardiovascular and cerebrovascular events (MACCE). While physical activity is known to lower MACCE risk, improve long-term prognosis, and enhance quality of life, studies consistently report inadequate physical activity levels in this population. The relationships and potential mechanisms linking physical activity with its influencing factors remain incompletely understood, limiting the development of effective interventions. Therefore, this study aimed to identify key factors affecting physical activity and examine their underlying pathways in elderly post-PCI patients. A cross-sectional study was conducted in Zhengzhou, China, from December 2024 to May 2025. Four hundred and eighty elderly individuals aged over 60 years who had undergone PCI completed the International Physical Activity Questionnaire-Long Form, Coronary Heart Disease Patients’ Rehabilitation Exercise Questionnaire, Cardiac Rehabilitation Exercise Self-efficacy Scale, 7-item Generalized Anxiety Disorder Scale, Patient Health Questionnaire-9, and a socio-demographic data sheet. Data analysis was performed using SPSS 25.0 for descriptive statistics, Spearman correlation, and binary logistic regression. Mediation analysis was conducted via structural equation modeling (SEM) in MPLUS 8.3. 52.90% of participants did not meet the recommended physical activity guidelines. Physical activity self-efficacy significantly mediated the relationship between physical activity knowledge and physical activity (β = 0.730, P < 0.001). Although anxiety and depression symptoms were not directly associated with physical activity (P > 0.05), they exerted significant indirect negative effects through reduced physical activity self-efficacy(anxiety: β=-0.287, 95% confidence interval [-0.553,-0.118]; depression: β=-0.394, 95% confidence interval [-0.683,-0.204]). This study found that the prevalence of being physically inactive was high in elderly adults after PCI. The present study’s findings suggested that healthcare providers should try to enhance physical activity self-efficacy, knowledge, and positive emotions of elderly adults after PCI to improve their physical activity with a focus on physical activity self-efficacy. Registry: The Central China Cardiovascular Hospital in Fuwai, TRN: 2025 No. 29, Registration date: 12 March 2025. Registry: The First Affiliated Hospital of Henan University of Traditional Chinese Medicine’s Ethics Committee, TRN:2025HL-030-01, Registration date: 13 February 2025.