Effects of a multi-theory model-based physical activity intervention on recovery outcomes in postoperative non-small cell lung cancer patients: a non-randomized controlled trial

Physical inactivity remains a persistent challenge following surgery for non-small cell lung cancer (NSCLC), exacerbating functional decline and symptom burden. This study aimed to develop and evaluate the efficacy of a physical activity (PA) intervention grounded in the Multi-Theory Model (MTM) to enhance recovery outcomes in postoperative NSCLC patients. A non-randomized controlled trial was conducted involving 82 postoperative NSCLC patients, assigned to either an intervention group ( n = 41) or a control group ( n = 41) receiving routine care. The MTM-based intervention integrated participatory dialogue, collaborative goal setting, individualized exercise prescriptions, and digital health support (via WeChat and activity monitoring). This structured program spanned 8 weeks, covering both in-hospital (initiation) and home-based (maintenance) phases. Primary outcomes were physical activity levels and compliance with physical activity recommendations. Secondary outcomes included exercise self-efficacy, symptom burden, and pulmonary function. Intervention effects were analyzed using linear mixed-effects models. Physical activity levels were significantly higher in the intervention group than in the control group at 4 and 8 weeks (T2 and T3; P = 0.003 and P < 0.001, respectively; Cohen’s d = 0.70 and 1.35). Physical activity compliance was significantly better in the intervention group at 1, 4, and 8 weeks (T1, T2, and T3; P = 0.041, P < 0.001, and P < 0.001, respectively; Cohen’s d = 0.50, 1.49, and 1.11). Exercise self-efficacy was also significantly higher in the intervention group at T2 and T3 (both P < 0.001; Cohen’s d = 1.05 and 1.38). For symptom burden, a significant between-group difference was observed only at T1 ( P = 0.008; Cohen’s d = 0.73), with the intervention group reporting transiently higher symptom scores; this difference was not sustained at T2 or T3, and both groups showed substantial within-group improvement over time. Regarding pulmonary function, the intervention group showed significantly greater improvements in forced vital capacity (FVC; adjusted MD = 0.55 L, 95% CI: 0.36 to 0.73, P < 0.001), forced expiratory volume in one second (FEV1; adjusted MD = 0.22 L, 95% CI: 0.08 to 0.36, P = 0.002), and the FEV1/FVC ratio (adjusted MD = 6.62%, 95% CI: 4.41 to 8.81, P < 0.001) at T3, while the between-group difference in diffusing capacity for carbon monoxide (DLCO) was not statistically significant (adjusted MD = 0.36, 95% CI: -0.01 to 0.74, P = 0.058). The trial recorded a low attrition rate of 3.66%, with no intervention-related adverse events reported. The MTM-based PA intervention significantly enhanced physical activity, compliance, exercise self-efficacy, and ventilatory function in postoperative NSCLC patients. This study offers a feasible, theory-driven framework for integrating structured exercise into standard postoperative rehabilitation. Future large-scale randomized trials are warranted to assess long-term sustainability. This trial was retrospectively registered with the Chinese Clinical Trial Registry (Registration Number: ChiCTR2600121690). The registration was completed on 1 April 2026. The delay in registration was attributable to the investigators’ limited familiarity with prospective registration requirements at the time the trial was initiated; no protocol amendments were made after registration.