Researchers found better cardiopulmonary fitness was linked to reduced decline in lung function over time.
Researchers found that people with better cardiopulmonary fitness demonstrated a lesser decline in lung function over 20 years than those with poorer cardiopulmonary fitness.
Cardiopulmonary fitness is a measure of heart and lung function during rest and physical activity.
Dr. Lillian Benck, of the Northwestern University Feinberg School of Medicine in Chicago, IL, and colleagues recently presented their findings at the American Thoracic Society (ATS) 2016 International Conference in San Francisco, CA.
Dr. Benck notes that as we age, our lung function declines, though the rates of decline vary from person to person.
"What is less known is, beyond smoking, what factors affect this rate of decline," she adds.
For their study, the researchers analyzed data from the Coronary Risk Development in Young Adults Study (CARDIA), involving 5,115 healthy black and white individuals aged 18-30.
Over a 20-year period, participants' cardiopulmonary fitness was measured through a graded treadmill test, which was performed at study baseline and repeatedly thereafter.
Subject pulmonary function - a measure of how well the lungs are working - was assessed at each cardiopulmonary fitness test.
This was done by measuring participants' forced expiratory volume in 1 second (FEV1) - the amount of air expired in 1 second - and forced vital capacity (FVC) - the amount of air exhaled forcefully and quickly following maximum air inhalation.
Lung health better preserved with high cardiopulmonary fitness
The researchers found that participants who had the greatest cardiopulmonary fitness at study baseline experienced the least decline in pulmonary function each year over the 20-year period.
Subjects who experienced the greatest decline in cardiopulmonary fitness during the 20-year period showed the greatest reduction in FEV1 and pulmonary function, the researchers report.
However, participants who maintained or improved their cardiopulmonary fitness experienced the lowest decline in pulmonary function over 20 years.
The team says the results remained statistically significant after accounting for subjects' age, body mass index (BMI), and even their smoking status - a key risk factor for lung disease.
While the study is unable to confirm cause and effect between fitness and lung function decline, Dr. Benck believes the findings highlight the importance of achieving and maintaining good fitness.
"[...] declining lung function is known to increase overall morbidity and mortality even in the absence of overt pulmonary disease.
Fitness early in life and at middle age appears to attenuate this natural decline."
Dr. Lillian Benck
The researchers hope the CARDIA study will continue to shed light on whether fitness can reduce lung function decline, as well as whether it can lower the risk of lung disease.