Effects of Isometric Handgrip Exercise Training on Lung Function in COPD Patients

Background: Chronic obstructive pulmonary disease (COPD) is associated with persistent airflow limitation and systemic deconditioning that reduce exercise tolerance and worsen functional outcomes. Low-cost adjunct exercise modalities that can augment rehabilitation effects remain clinically relevant. Objective: To determine the effects of adding isometric handgrip (IHG) exercise training to resistance training on lung function and functional exercise capacity in COPD patients. Methods: A single-center, parallel-group randomized clinical trial enrolled 48 ambulatory patients with GOLD stage II–III COPD and randomized them to IHG plus resistance training (n=24) or resistance training alone (n=24) for 8 weeks. Spirometry outcomes included forced expiratory volume in one second (FEV1), forced vital capacity (FVC), and FEV1/FVC ratio, and functional capacity was assessed with the 6-minute walk test (6MWT). Parametric analyses compared within-group pre–post changes and between-group post-intervention differences. Results: Both groups improved after intervention; however, the combined program produced larger post-intervention values. FEV1 was higher in the combined group (2.4047±0.4619 vs 1.9320±0.3823 L; MD 0.4727; 95% CI 0.2261–0.7193; p<0.01) and FVC was higher (3.4688±0.5834 vs 3.0949±0.4941 L; MD 0.3739; 95% CI 0.0596–0.6882; p=0.021). 6MWT distance was also higher (422.94±31.03 vs 391.58±24.00 m; MD 31.36; 95% CI 15.24–47.48; p<0.001). Conclusion: Adding IHG training to resistance exercise enhanced pulmonary function and walking capacity more than resistance training alone in GOLD II–III COPD. Keywords: Chronic obstructive pulmonary disease; isometric handgrip; resistance training; spirometry; FEV1; forced vital capacity; six-minute walk test; pulmonary rehabilitation.