The case for exercise in managing chronic lung disease

If you have chronic obstructive pulmonary disease, you might think you can't — or shouldn't — exercise. But you really must.

Chronic obstructive pulmonary disease (COPD) includes chronic bronchitis and emphysema. More than 12 million Americans have been diagnosed with the disease, most of them current or former smokers. COPD is the fourth leading cause of death in the United States: each year, roughly 120,000 people — more women than men — succumb to it. But people often live with COPD for many years, and it takes a major part of its toll by sapping the strength and stamina needed for work, social activities, and leisure-time pursuits.