Prevention of Post-exercise Muscle Fatigue and Effect on Exercise Training in Severe Patients With COPD. (QUADRIVEND)

Prevention of Post-exercise Muscle Fatigue and Effect on Exercise Training in Severe Patients With COPD.

Prevention of Post-exercise Muscle Fatigue Using a Non Invasive Ventilation and Effect on Exercise Training in Severe Patients With COPD. QUADRIVEND Study

In patients with severe Chronic Obstructive Pulmonary Disease (COPD), exercise tolerance is severely impaired due to a ventilatory limitation, levelling off the intensity of exercise. This reduces the physiological benefit of pulmonary rehabilitation. In these patients, it is then proposed to add an Inspiratory Pressure Support (IPS) in order to increase the intensity and the duration of every training session. In a preliminary study, the investigators showed that IPS applied during an exhaustive cycling exercise allowed to prevent the onset of post-exercise quadriceps fatigue evaluated by the endurance time to isotonic quadriceps contractions (TlimQ). The aim of this study is to determine the relationship between the prevention of post-exercise fatigue (TlimQ) and the change in training load (intensity x time x number of sessions) during a pulmonary rehabilitation programme. At the beginning of the training programme, 25 patients will be evaluated for TlimQ after a cycling exercise (70% maximal workload) with and without IPS in random order. The training load was then monitored at every exercise session of the programme.

The initial evaluation is performed using an Inspiratory Pressure Support. After the training, the final evaluation is performed using an Inspiratory help (sham ventilation).

The initial evaluation is performed using an inspiratory help (sham ventilation). After the training, the final evaluation is performed using an Inspiratory Pressure Support.

The Inspiratory Pressure Support is used to increase the intensity and the duration of training session. For the sham ventilation, the device deliver a non effective quantity of oxygen.

The Inspiratory Pressure Support is used to increase the intensity and the duration of training session. For the sham ventilation, the device deliver a non effective quantity of oxygen.

Strength of the correlation between the change of TlimQ (min) and the training load calculated as intensity (in watts) x duration of the session (minute) x number of sessions

At the beginning of the programme, we evaluate the influence of IPS on TlimQ (visits 2 and 3). After the training period, we repeated the same evaluations (visits 23 and 24). Then, we will compare this difference before and after the training period, and we will seek for a relation with the training load.

We compare the endurance time to isotonic quadriceps contractions after a cycling exercice until exhaustion with and without IPS, at the beginning of the training period.

relationship between the change in the endurance to cycling exercise without and with IPS and the change in TlimQ

we will compare the difference in endurance to exercise with IPS and the difference in endurance to isotonic quadriceps contractions

relationship between the change in the endurance to cycling exercise with IPS and the change in TlimQ

we will seek for a relationship between the changes in the endurance time to cycling exercise without or with IPS and the variation in endurance to isotonic quadriceps contractions following cycling exercise

variation of TlimQ after a cycling exercice untill fatigue without IPS at the beginning and the end of pulmonary rehabilitation evaluated by the endurance time to isotonic quadriceps contractions

variation of TlimQ after a cycling exercice untill fatigue with IPS at the beginning and the end of pulmonary rehabilitation evaluated by the endurance time to isotonic quadriceps contractions

Inclusion Criteria: Severe COPD patients in stable condition (Gold class 3 or 4) Ventilatory limitation to exercise during the incremental cardiopulmonary exercise test (at least one of the following criteria) : No breathing reserve Exercise hypoventilation (increase arterial PCO2> 5 mmHg) Maximal workload <50 Watts Exclusion Criteria: IPS not tolerated during a preliminary cycling exercise test Enable to perform the exercise tests or the rehabilitation programme Decline to participate