Silva, Fernanda M.Leitão Ferreira, José PedroTeixeira, Ana M.Monteiro, DiogoDuarte-Mendes, Pedro2025-06-132025-06-132025-05-30Silva, F.M., Ferreira, J.P., Teixeira, A.M. et al. The effect of smoking on lung function changes during a 16-week combined exercise program in middle-aged workers: a latent growth curve analysis. Eur J Appl Physiol (2025). https://doi.org/10.1007/s00421-025-05819-w1439-63191439-6327http://hdl.handle.net/10400.8/13231Purpose To investigate the longitudinal changes in lung function of sedentary middle-aged workers over a 16-week combined exercise training program. Methods Thirty-six sedentary workers (53.70 ± 6.92 years old) were randomly allocated to either a combined aerobic and resistance training program (n = 18) or a control group (n = 18). Lung function was evaluated through spirometry using a portable flow spirometer (Spiropalm 6MWT, Cosmed, Italy). Predicted percentages of forced vital capacity (FVC), forced expiratory volume in the first second (FEV1), FEV1/FVC ratio, and mean forced expiratory flow between 25 and 75% of exhaled FVC (FEF25–75) were analyzed. Assessments were performed at baseline (M1), after 8-week (M2) and 16-week follow-up (M3). The changes in lung function were analyzed using the Latent Growth Curve Modeling that estimated interindividual and intraindividual growth paths. Results Smoking status revealed a significant effect on lung function growth with significant paths to intercept and slope for all models in both groups. The exercise group participants who are non-smokers revealed higher increases in FVC% (β = .22), FEV1% (β = .08), FEV1/FVC% ratio (β = .19), and FEF25–75% (β = .06) compared to those who are smokers from M1 to M3. The control group revealed a lower growth in lung function from M1 to M3, with a lower slope observed in smokers compared to non-smokers for FVC% (β = − .44), FEV1% (β = −.41), FEV1/FVC% (β = − .98), and FEF25–75% (β = − .52). Conclusion Our findings suggest that a 16-week combined training program is an effective strategy to improve lung function among sedentary workers, with a higher magnitude of improvement for non-smokers compared to smokers.engHealth promotionAgingSmokingspirometryExercise trainingresearch article2025-06-12cv-prod-450595610.1007/s00421-025-05819-w