[The effect of controlled and uncontrolled dynamic lower extremity training in the rehabilitation of patients with chronic obstructive pulmonary disease]

Abstract

Pulmonary rehabilitation has become a part of the integrated management of patients with chronic obstructive pulmonary disease (COPD). The lower extremity dynamic training has been proved to be the most effective element of the program.

Objective: Does the supervised training have more favorable effect in case of similar program?

Patients and methods: In two groups: 54 patients, supervised (group K, n = 22) and not supervised (group NK, n = 32) by physiotherapists, chosen at random have been investigated. Both groups consisted of hospitalized patients of the same severity (forced expiratory volume in one second) [FEV1 (average +/- SD)]: K: 51.0 +/- 16.1 vs. NK: 51.9 +/- 15.6% pred). Group K performed physiotherapist-supervised cycling training in the Pulmonology Ambulance Unit 3-4 times a week for 45 minutes doing an 8-week period and group NK performed training in the form of cycling, stepping on stairs or dynamic walking at home with the same duration, weekly periodicity and time interval.

Results: After rehabilitation vital capacity (VC) (K: 3.0 +/- 0.8 vs. 3.3 +/- 0.7 l, p < 0.05), emphysema ratio (RV/TLC): K: 53.5 +/- 10.1 vs. 51.6 +/- 9.9, p < 0.05) in the supervised group, and alveolar volume (VA) in the not supervised group (NK: 4.3 +/- 0.9 vs. 4.7 +/- 0.9 l, p < 0.05) significantly improved. Improvement of exercise capacity was more effective in group K (K: 92.7 +/- 33.9 vs. 106.4 +/- 34.5 W, p < 0.001; NK: 95.8 +/- 36.7 vs. 99.9 +/- 35.1 W, p < 0.05). In both groups aerobic capacity (VO2: K: 1.2 +/- 0.4 vs. 1.3 +/- 0.4 l/min, p < 0.01, NK: 1.1 +/- 0.4 vs. 1.2 +/- 0.4 l/min, p < 0.01; VO2/kg: K: 16.1 +/- 5.5 vs. 17.5 +/- 5.8 ml/kg/mm, p < 0.01, NK: 16.2 +/- 5.3 vs. 16.7 +/- 4.8 ml/kg/ min, p < 0.01) and anaerobic threshold level [AT (pred VO2%)] (K: 36.6 +/- 9.8 vs. 42.8 +/- 10.2%, p < 0.001; NK: 40.8 +/- 12.0 vs. 44.6 + 11.6%, p < 0.001) significantly improved. Heart rate reserve: (K: 17.7 +/- 22.7 vs. 28.8 +/- 31.5 l/min, p < 0.01; NK: 20.4 +/- 21.2 vs. 25.0 +/- 21.6 l/min, p < 0.01) improved at the same level of exercise. The Borg scale of dyspnea (0-10): (K: 6.4 +/- 2.5 vs. 5.7 +/- 2.7, p < 0.05; NK: 7.5 +/- 1.8 vs. 6.9 +/- 2.2, p < 0.05) was reduced and quality of life score (0-24): K: 11.5 +/- 0.7 vs. 9.0 +/- 2.8, p < 0.005; NK: 11.6 +/- 2.3 vs. 7.0 +/- 1.9, p < 0.005) was improved.

Conclusion: In both group dynamic lower extremity training caused improvement in exercise capacity. The favorable metabolic effect of training was shown by the change of anaerobic threshold resulting in less carbon dioxide production during analogous exercise. This reduction led to less ventilation reducing the work of breathing in supervised group. The more favorable adaptation taking place in the group supervised by physiotherapists might have resulted from the controlled higher intensity of the training.