Reliability, Sensitivity and Validity of the 6 Minute Step Test in Chronic Obstructive Pulmonary Disease (COPD) Patients

• First "Six Minute Step Test" Performance [ Time Frame: First day of the protocol or the day after, by sortition ] [ Designated as safety issue: No ]
  This test will be conducted by the "Rater 1", the patient will climb and down one 20cm step during six minute. The performance will be evaluated by the number of the climbs.
• Second "Six Minute Step Test" Performance [ Time Frame: 30 minutes after the first 6MST ] [ Designated as safety issue: No ]
  This test will be conducted by the "Rater 1", the patient will climb and down one 20cm step during six minutes. The performance will be evaluated by the number of the climbs.
• Third "Six Minute Step Test" Performance [ Time Frame: Seven days after the first test, or 30 minutes after the third 6MST, by sortition ] [ Designated as safety issue: No ]
  This test will be conducted by the "Rater 2", the patient will climb and down one 20cm step during six minutes. The performance will be evaluated by the number of the climbs.

• First "Six Minute Walk Test" Distance [ Time Frame: First day of the protocol or the day after, by sortition ] [ Designated as safety issue: No ]
  This test will be conducted by the "Rater 1", the subject will walk as fast as it could in a 30m corridor during 6 minutes. The performance will be the distance (meters)that it walk.
• Second "Six Minute Walk Test" Distance [ Time Frame: 30 minutes after the first 6MWT ] [ Designated as safety issue: No ]
  This test will be conducted by the "Rater 1", the subject will walk as fast as it could in a 30m corridor during 6 minutes. The performance will be the distance (meters)that it walk.
• Third "Six Minute Walk Test" Distance [ Time Frame: Seven days after the first test or 30 minutes after the Third 6MWT, by sortition ] [ Designated as safety issue: No ]
  This test will be conducted by the "Rater 2", the subject will walk as fast as it could in a 30m corridor during 6 minutes. The performance will be the distance (meters)that it walk.
• "Body-Mass index, Airflow Obstruction, Dyspnea, Exercise Capacity" Index (BODE index) [ Time Frame: First day of the protocol, after the tests ] [ Designated as safety issue: No ]
  It will be evaluated only in the COPD patients (Groups III, IV and V).
• First "Six Minute Walk Test" exertion perception [ Time Frame: First day of the protocol or the day after, by sortition ] [ Designated as safety issue: No ]
  This test will be conducted by the "Rater 1", the subject will walk as fast as it could in a 30m corridor during 6 minutes. The Exertion Perception will be evaluated by the CR10 BORG scale, at rest and every two minutes of the test.
• Second "Six Minute Walk Test" exertion perception [ Time Frame: 30 minutes after the first 6MWT ] [ Designated as safety issue: No ]
  This test will be conducted by the "Rater 1", the subject will walk as fast as it could in a 30m corridor during 6 minutes. The Exertion Perception will be evaluated by the CR10 BORG scale, at rest and every two minutes of the test.
• Third "Six Minute Walk Test" Exertion Perception [ Time Frame: Seven days after the first test or 30 minutes after the Third 6MWT, by sortition ] [ Designated as safety issue: No ]
  This test will be conducted by the "Rater 2", the subject will walk as fast as it could in a 30m corridor during 6 minutes. The Exertion Perception will be evaluated by the CR10 BORG scale, at rest and every two minutes of the test.
• First "Six Minute Step Test" Exertion Perception [ Time Frame: First day of the protocol or the day after, by sortition ] [ Designated as safety issue: No ]
  This test will be conducted by the "Rater 1", the patient will climb and down one 20cm step during six minute. The Exertion Perception will be evaluated by the CR10 BORG scale, at rest and every two minutes of the test.
• Second "Six Minute Step Test" Exertion Perception [ Time Frame: 30 minutes after the first 6MST ] [ Designated as safety issue: No ]
  This test will be conducted by the "Rater 1", the patient will climb and down one 20cm step during six minute. The Exertion Perception will be evaluated by the CR10 BORG scale, at rest and every two minutes of the test.
• Third "Six Minute Step Test" Exertion Perception [ Time Frame: Seven days after the first test, or 30 minutes after the third 6MST, by sortition ] [ Designated as safety issue: No ]
  This test will be conducted by the "Rater 2", the patient will climb and down one 20cm step during six minute. The Exertion Perception will be evaluated by the CR10 BORG scale, at rest and every two minutes of the test.
• First "Six Minute Walk Test" Peripheral Oxygen Saturation [ Time Frame: First day of the protocol or the day after, by sortition ] [ Designated as safety issue: No ]
  This test will be conducted by the "Rater 1", the subject will walk as fast as it could in a 30m corridor during 6 minutes. It will be evaluated by a pulse oxymeter at rest and every two minutes of the test.
• Second "Six Minute Walk Test" Peripheral Oxygen Saturation [ Time Frame: 30 minutes after the first 6MWT ] [ Designated as safety issue: No ]
  This test will be conducted by the "Rater 1", the subject will walk as fast as it could in a 30m corridor during 6 minutes. It will be evaluated by a pulse oxymeter at rest and every two minutes of the test.
• Third "Six Minute Walk Test" Peripheral Oxygen Saturation [ Time Frame: Seven days after the first test or 30 minutes after the Third 6MWT, by sortition ] [ Designated as safety issue: No ]
  This test will be conducted by the "Rater 2", the subject will walk as fast as it could in a 30m corridor during 6 minutes. It will be evaluated by a pulse oxymeter at rest and every two minutes of the test.
• First "Six Minute Step Test" Peripheral Oxygen Saturation [ Time Frame: First day of the protocol or the day after, by sortition ] [ Designated as safety issue: No ]
  This test will be conducted by the "Rater 1", the patient will climb and down one 20cm step during six minute. It will be evaluated by a pulse oxymeter at rest and every two minutes of the test.
• Second "Six Minute Step Test" Peripheral Oxygen Saturation [ Time Frame: 30 minutes after the first 6MST ] [ Designated as safety issue: No ]
  This test will be conducted by the "Rater 1", the patient will climb and down one 20cm step during six minute. It will be evaluated by a pulse oxymeter at rest and every two minutes of the test.
• Third "Six Minute Step Test" Peripheral Oxygen Saturation [ Time Frame: Seven days after the first test or 30 minutes after the Third 6MST, by sortition ] [ Designated as safety issue: No ]
  This test will be conducted by the "Rater 2", the patient will climb and down one 20cm step during six minute. It will be evaluated by a pulse oxymeter at rest and every two minutes of the test.
• First "Six Minute Walk Test" Variation in Heart Rate [ Time Frame: First day of the protocol or the day after, by sortition ] [ Designated as safety issue: No ]
  This test will be conducted by the "Rater 1", the subject will walk as fast as it could in a 30m corridor during 6 minutes. It will be evaluated by a cardio monitor at rest and every two minutes of the test.
• Second "Six Minute Walk Test" Variation in Heart Rate [ Time Frame: 30 minutes after the first 6MWT ] [ Designated as safety issue: No ]
  This test will be conducted by the "Rater 1", the subject will walk as fast as it could in a 30m corridor during 6 minutes. It will be evaluated by a cardio monitor at rest and every two minutes of the test.
• Third "Six Minute Walk Test" Variation in Heart Rate [ Time Frame: Seven days after the first test or 30 minutes after the Third 6MWT, by sortition ] [ Designated as safety issue: No ]
  This test will be conducted by the "Rater 2", the subject will walk as fast as it could in a 30m corridor during 6 minutes. It will be evaluated by a cardio monitor at rest and every two minutes of the test.
• First "Six Minute Step Test" Variation in Heart Rate [ Time Frame: First day of the protocol or the day after, by sortition ] [ Designated as safety issue: No ]
  This test will be conducted by the "Rater 1", the patient will climb and down one 20cm step during six minute. It will be evaluated by a cardio monitor at rest and every two minutes of the test.
• Second "Six Minute Step Test" Variation in Heart Rate [ Time Frame: 30 minutes after the first 6MST ] [ Designated as safety issue: No ]
  This test will be conducted by the "Rater 1", the patient will climb and down one 20cm step during six minute. It will be evaluated by a cardio monitor at rest and every two minutes of the test.
• Third "Six Minute Step Test" Variation in Heart Rate Variation [ Time Frame: Seven days after the first test or 30 minutes after the Third 6MST, by sortition ] [ Designated as safety issue: No ]
  This test will be conducted by the "Rater 2", the patient will climb and down one 20cm step during six minute. It will be evaluated by a cardio monitor at rest and every two minutes of the test..

Chronic Obstructive Pulmonary Disease (COPD) leads to a reduction in exercise capacity that affects the quality of life and increases mortality of these patients. So, exercise tests are considered as an essential component of the clinical evaluation of the patients with COPD. The objective of this study is to evaluate the reproducibility sensitivity and validity of the Six Minute Step Test (6MST) in patients with COPD and in health volunteers, and verify its relation with the "Body-Mass Index, Airways Obstruction, Dyspnea and Exercise Capacity" Index (BODE). This Observational, Transversal, Prospective study will be conducted in the "Unidade Especial de Fisioterapia Respiratória", of the "Universidade Federal de São Carlos". To participate in this study, 120 subjects, both gender, will be invited and will be allocated in five groups: Group I (30 healthy young subjects of 17 to 27 years old), Group II (30 healthy elderly individuals of 60 to 75 years old), and patients COPD, 60 to 80 years old, with mild, moderate, severe and very severe obstruction determined by the forced expiratory volume in one second (FEV1) by forced vital capacity (FVC) relation "FEV1/FVC" <70% and FEV1 in predict percentage < 80% composing the Group III (20 COPD patients in GOLD stage I), Group IV (20 COPD patients in GOLD stage II) and Group V (20 patients COPD stages III and IV). All subjects will be submitted to body composition and anthropometric assessment, pulmonary function test, three 6-minutes walk test (6MWT) and three 6MST. Furthermore, the patients of the groups III, IV and V will answer the Modified Medical Research Council (mMRC) scale, and BODE index will be calculated to each of them.

COPD patients, Healthy Young Subjects, and Healthy Elderly subjects, from a community sample of São Carlos city - São Paulo State - Brazil.

• Healthy Young Subjects
  Subjects apparently healthy, with age of 18 to 27 years old.
• Healthy Elderly subjects
  Subjects apparently healthy, with age of 60 to 75 years old.
• COPD Patients in GOLD stage I
  Patients with clinical and spirometric diagnosis of COPD, with FEV1>80%
• COPD Patients in GOLD Stage II
  Patients with clinical and spirometric diagnosis of COPD, with FEV1<80% and >50%
• COPD patients in GOLD stage III and IV
  Patients with clinical and spirometric diagnosis of COPD, with FEV1<50%

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Inclusion Criteria:

• Young and elderly healthy subjects presented pulmonary function within the normal range, confirmed by spirometry
• Patients with clinical and spirometric diagnosis of COPD

Exclusion Criteria:

• Lung disease exacerbated
• Decompensated heart disease
• Rheumatic, neurological or orthopedic disease, preventing them from doing the tests by limiting the exercise
• Peripheral oxygen saturation < 80% without physical effort
• Subjects who does not complete a given test or protocol