*8.2.3 Flexibility training*

Many COPD patients suffer from modification in the structure of their chest wall due to hyperinflation, hypertrophy of the accessory respiratory muscles and physical inactivity. This further leads to changes in the posture and reduced mobility. To prevent this from happening, COPD patients undergo flexibility training as a part of the pulmonary rehabilitation program.

Flexibility exercises lead to improved mobility by increasing joint range of motion, reducing joint stiffness, better posture and increment in vital capacity [45]. Gentle stretching exercises with full body movements, coordinated with breathing techniques are appropriate for COPD patients [65, 98, 99].

This kind of workout teaches the patient the influence of body movements on respiration. Since these exercises are done at a slower pace without any resistive loads, they can be used during warm up or cool down periods of the program. Limited research has been done on adequate duration and intensity of stretching exercises. General recommendation are to perform stretching of major muscle groups in the upper and lower extremities 2–3 days per week at the minimum [100]. Benefits of this training can be measured by documenting reduction in subjective perception of stiffness, reduced incidence of back pain and joint injuries.
