Which statement best describes how COPD affects exercise tolerance?

Which statement best describes how COPD affects exercise tolerance?

• A. Patients typically have improved exercise tolerance in the morning.
• B. Exercise tolerance is unaffected by secretions.
• C. Patients may have reduced exercise capacity, especially in the morning due to accumulated pulmonary secretions.
• D. Exercise tolerance is only affected after meals.

Answer: (C)

The main idea is that COPD lowers how well the body can tolerate exercise because the airways are narrowed, mucus clearance is impaired, and the lungs can’t deliver enough air to meet the muscles’ demands during activity. This leads to more breathing effort, faster fatigue, and more shortness of breath during exercise. In COPD, overnight mucus can pool and become thicker, especially with chronic bronchitis. When morning comes, there is more airway resistance and coughing, which makes breathing harder just as you start activity. That combination—increased work of breathing, reduced ventilation, and poorer gas exchange—tends to blunt exercise capacity, so people often tolerate less exertion in the morning. The other ideas don’t fit with the typical COPD pattern. Secretions do affect exercise tolerance, and exercise capacity isn’t limited only after meals. It’s not accurate to say tolerance is unaffected by secretions or that it improves in the morning.

The main idea is that COPD lowers how well the body can tolerate exercise because the airways are narrowed, mucus clearance is impaired, and the lungs can’t deliver enough air to meet the muscles’ demands during activity. This leads to more breathing effort, faster fatigue, and more shortness of breath during exercise.

In COPD, overnight mucus can pool and become thicker, especially with chronic bronchitis. When morning comes, there is more airway resistance and coughing, which makes breathing harder just as you start activity. That combination—increased work of breathing, reduced ventilation, and poorer gas exchange—tends to blunt exercise capacity, so people often tolerate less exertion in the morning.

The other ideas don’t fit with the typical COPD pattern. Secretions do affect exercise tolerance, and exercise capacity isn’t limited only after meals. It’s not accurate to say tolerance is unaffected by secretions or that it improves in the morning.