The walking capacity assessment in the respiratory patient.

Exercise testing is commonly used in respiratory patients to assess their degree of disability, prognosis for survival, presence of exercise-induced hypoxemia and response to treatment. Recently, simple exercise tests, which are based on walking, have been developed and are increasingly being used both for clinical and research purposes. The 6-min walk test (6-MWT) is the most widely used and simply consists in the measurement of the distance walked in 6 min. The 6-MWT is self-paced and differs from the shuttle walking test, which is externally paced via a recorded metronome and entails incrementally faster speeds. Although the field walking tests do not require complex equipment, they can provide reliable and useful clinical information. This review deals with the validity, reliability and interpretation of these walking tests in the assessment of patients with chronic respiratory disease.