[Value of individualized rehabilitation at the ventilatory threshold level in moderately severe chronic obstructive pulmonary disease]

Abstract

In order to study the efficiency of individual training programs at the ventilatory threshold level, twenty COPD patients were randomized into two groups and studied over a two-month period. At the start, during, and at the end of the study all subjects performed incremental exercise tests. The trained group (59.60 SEM +/- 2.75 years) walked four times a week at the heart rate corresponding to the metabolic level of ventilatory threshold. The other group served as controls (58.2 +/- 1.80 years). A marked increase in the symptom-limited oxygen consumption (+/- 25%) (p < 0.01), the maximal ventilation (+20%) (p < 0.01), and the ventilatory threshold (+19%) (p < 0.05) was found in the trained group. No modification was recorded in the control group. The ventilatory pattern at submaximal intensities expressed in percentage of the initial oxygen consumption showed significant differences between groups, the trained-group ventilation decreased at 50% and 75% VO2 sl (p < 0.05). The breathing frequency also decreased at 50% and 75% VO2 sl (p > 0.05). Moreover, we observed an increase in the oxygen pulse at 50% VO2 sl (p < 0.05). In conclusion, this study demonstrates that individualized training at the ventilatory threshold level increases exercise tolerance and produces better ventilatory comfort in COPD patients.