Different Modalities of Exercise Training in COPD With Chronic Respiratory Failure (CRF)

Advanced Chronic Obstructive Pulmonary Disease (COPD) is a condition with a negative prognosis that causes symptoms such as wheezing and fatigue that dramatically reduce the quality of life of the person with the disease. Typically, the advanced stage of COPD is characterized by a fluctuating pattern and recurrent hospitalizations, and by a vicious circle in which dyspnoea increases and exercise tolerance reduces, causing depression with social isolation, low quality of life and increased risk of death. Muscle dysfunction in these patients contributes together with dynamic hyperinflation to increased fatigue and dyspnoea during exercise, leading to early interruption of exertion, before reaching the maximal aerobic capacity. The European and American guidelines of the American Thoracic Society / European Respiratory Society relating to the patient with COPD emphasize the need for the patient to undergo Respiratory Rehabilitation (RR) programs. The RR should include training programs as they improve exercise capacity, dyspnoea and quality of life more than programs that do not include training. To our knowledge, no study has been performed in COPD with chronic respiratory failure (CRF) patients to evaluate the effects of High Interval Training compared to continuous submaximal training. Moreover, no different interval training protocols have been compared. However, studies conducted on healthy subjects or on other pathologies, show how the interval training protocol induces, in a specific and diversified way, physiological modifications to the cardio-respiratory and muscular systems. In COPD patients with respiratory failure with marked muscular dysfunction and associated systemic changes (systemic inflammation, vascular changes, pulmonary hypertension, right heart failure, etc.), the evaluation of the best training program would reinforce the rehabilitative indications not yet fully proposed in the Guidelines. Moreover, the evaluation of the response to different training stimuli could provide important information on the reversibility of the intolerance to the effort in this patient population. Primary aim of this study will be to evaluate the physiological effects on exercise tolerance of three training modalities performed in an intra-hospital setting (classic endurance training compared to two high-intensity interval programs - Long Interval Training and Short Interval training) in a population of COPD patients with chronic hypoxemic respiratory failure.