Objective To explore the influencing factors of physical activity behavior change in lung cancer patients and provide a basis for developing targeted intervention programs.

Methods A descriptive qualitative research method was employed. Using purposive sampling, 18 lung cancer patients and 10 healthcare professionals were selected for semi-structured interviews from October to December 2023. The health action process approach (HAPA) theory was used as the framework, and directed content analysis was applied to analyze the data.

Results The barriers to physical activity behavior change in lung cancer patients were distilled into six themes: insufficient risk perception, negative outcome expectations, self-doubt and behavior avoidance tendencies, challenges in persistence and risk of interruption, lack of behavioral intention and demand, and absence of action and coping plans. The facilitating factors were divided into six themes: perception of the potential hazards of insufficient physical activity, perception of the health benefits of physical activity, cultivation and development of self-efficacy, stimulation of motivation for activity, formulation of differentiated activity plans, and formulation of adaptive coping plans.

Conclusion Physical activity behavior in lung cancer patients is influenced by multiple factors. Targeted intervention strategies can be developed based on the HAPA theory to promote physical activity behavior change and improve physical activity levels.