Which factor contributes to higher caloric needs in chronic lung disease due to increased work of breathing?

Which factor contributes to higher caloric needs in chronic lung disease due to increased work of breathing?

• A. Decreased work of breathing
• B. No effect on caloric needs
• C. Increased work of breathing
• D. Decreased metabolic rate

Answer: (C)

When breathing is laborious, the respiratory muscles have to work harder and more often to move air through the lungs. That extra contraction and sustained activity consume more ATP and oxygen, so the body's overall energy expenditure rises. In chronic lung disease, this increased work of breathing becomes a steady source of caloric demand, meaning you need more calories to support the respiratory muscles and maintain overall energy balance. Other possibilities would not explain the rise in calories: reducing the work of breathing would lower energy needs, claiming there’s no effect ignores the clear rise in energy cost from the extra muscular effort, and a lower metabolic rate would decrease, not increase, caloric requirements.

When breathing is laborious, the respiratory muscles have to work harder and more often to move air through the lungs. That extra contraction and sustained activity consume more ATP and oxygen, so the body's overall energy expenditure rises. In chronic lung disease, this increased work of breathing becomes a steady source of caloric demand, meaning you need more calories to support the respiratory muscles and maintain overall energy balance.

Other possibilities would not explain the rise in calories: reducing the work of breathing would lower energy needs, claiming there’s no effect ignores the clear rise in energy cost from the extra muscular effort, and a lower metabolic rate would decrease, not increase, caloric requirements.