The aim of this study is to investigate weather the breathing exercises of Yoga are effective in altering clinical impact, anxiety, depression and quality of life in Chronic Obstructive Pulmonary Disease patients.

Introduction According to the Global Initiative for Chronic Lung Disease (GOLD), chronic obstructive pulmonary disease (COPD) is a common, preventable and treatable disease, characterized by a persistent not totally reversible limitation of air flow, with a progressively characteristic associated to the increase of inflammatory lungs and air pathways reactions to gas and harmful particles. It is one of the main morbid-mortality causes world wide and, thus, a social health matter. Dyspnoea is a recurrent stressful symptom of COPD, and is usually followed by anxiety, depression, and decreased quality of life.

Some studies have addressed the tolerance of yoga breathing exercises by COPD patients, and some have indeed found a decreased functional load of dyspnoea in such patients.

Thus, the aim of this study is to investigate the effects of the regular practice (training) of respiratory Yoga exercises (pranayamas) on the clinical impact and psychosocial aspects: anxiety, depression and quality of life in COPD patients as a complementary therapy to pulmonary rehabilitation.

Methods Participants Diagnosed COPD patients will be recruited from the Pulmonary Rehabilitation Ambulatory of the Clinical Hospital of the Faculty of Medicine of the University of São Paulo (HC-FMUSP). All participants will give written consent to participate of the study, and will be able to exit the study at any point without having to explain the reason.

Sample Size Calculation Based on effect expected proportion in controls of 0.05, assuming an odds ratio of 25, in a confidence level of 0.95, and a power of 0.8, the sample size for each group was 9, in a total sample size (both groups) of 18 participants.

Experimental Design This is a randomized controlled prospective clinical trial, with two groups: pulmonary rehabilitation for control group (PRG) and pulmonary rehabilitation plus Yoga group (YG).Randomization was carried out by numbered paper draw: 20 papers numbered from 1-20 were put in a bag from which participants took 1 paper each. Even numbers indicated PRG and odd ones indicated YG. Medication will not altered during study. Both groups will perform a 12-week pulmonary rehabilitation program, besides that, YG will perform 24 Yoga breathing sessions (2 times a week). Participants of both groups will answer questionnaires to evaluate clinical impact, anxiety, depression and quality of life at study entry and after 12 weeks.

Yoga Breathing Exercises Breathing exercises will be based on traditional Hatha Yoga texts (Hathapradipika and Gheranda Samhita). The chosen exercise was bhastrika pranayama (kapalabhati followed by surya bedhana). Kapalabhhati consists basically of 20 fast and vigorous abdominal contractions for expiration, followed by immediate and maximal relaxation of these muscles for inspiration, and surya bedhana is a slow inspiration through the right nostril, followed by a comfortable apnoea for the same time of air intake, and a slower yet comfortable expiration through the left nostril. During training, participants will be considered at peak training when they are able to perform 10 sets of bhastrika.

Pulmonary Rehabilitation will consist of 30 minutes of aerobic training (cycloergometer or treadmill) followed by resistance exercises for lower and upper limbs.

Evaluations Clinical impact of COPD will be accessed by the COPD Assessment Test; anxiety will be evaluated by Hospital Anxiety and Depression Scale; Quality of Life will be accessed by the self-reported Chronic Respiratory Questionnaire.

Statistical Analysis Intra-group comparisons between moments (pre vs. post treatment) will be done using a paired Student T-test (repeated measures). While inter-groups comparisons (PRG vs. YG) will be done using the independent measures Student T-test. Significance will be accepted when p<0.05. SPSS v.21 software will be used to process analysis.

Inclusion Criteria:

• COPD diagnosed classified as B, C or D according to the Global Initiative for Obstructive Lung Disease (GOLD);
• Optimized medical treatment.

Exclusion Criteria:

• Any other lung disease;
• Home use of oxygen therapy;
• Respiratory Yoga exercise training in the last 2 years;
• Current smokers.