Impact of Lower-Limb Endurance Training on Dyspnea and Lung Functions in Patients with COPD.

Background: Patients with chronic obstructive pulmonary disease (COPD) exhibit persistent dyspnea in daily activities and irreversible airflow obstruction. These will finally lead to an inability to carry on daily activities and markedly decrease their quality of life. Endurance training was considered as therapy modality to alleviate several symptoms experienced by COPD patients.

Aim: This study aims to identify the impact of lower-limb exercise on dyspnea and spirometry test results in COPD patients.

Methods: We performed a quasi-experimental study in July 2017 on 20 stable COPD patients divided both in group C and D according to GOLD 2017 criteria. Patients were given an individualised dose of stationary cycling twice a week for one month in which every session lasted 5-20 minutes gradually. Before and after rehabilitation program, pulmonary function tests were measured by spirometry to obtain per cent predicted of Forced Expiratory Volume in 1 second (FEV1), Forced Volume Capacity (FVC), Peak Expiratory Flow (PEF) and Forced Expiratory Flow at 25-75% of the pulmonary volume (FEF25-75), and dyspnea was measured by the mMRC index. Statistical analysis was performed by Wilcoxon and T-dependent test.

Results: Baseline value of FVC (49.6 ± 21.6%) increased significantly to 59.65 ± 16.53% after one month of endurance training program (p = 0.01). Surprisingly, there was also a significant increase in FEV1 value from 46.9 ± 21.7 to 52.9 ± 20.7% (p < 0.005). The increase of FVC and FEV1 in group C was slightly higher than in group D although not statistically significant (p = 0.29; p = 0.25 respectively). However, no difference was observed in PEF and FEF25-75 value (p > 0.05). Patients' dyspnea scale also showed significant improvement (p < 0.001) from mMRC median scale 2 (range 1-3) to 1 (range 0-2) in both groups C and D. There was no exacerbation found during rehabilitation program.

Conclusion: Twice a week lower-limb endurance training for one-month improved dyspnea and pulmonary function test results in COPD patients safely and effectively.