Adults who engage in regular aerobic exercise and muscle-strengthening activity are at significantly lower risk of death from the flu or pneumonia, a new study found.

Researchers from the Centers for Disease Control and Prevention and Brooke Army Medical Center studied 577,909 U.S. adults who had taken part in the National Health Interview Study from 1998-2018.

Study participants were followed for an average of 9.23 years, over which time 1,516 influenza and pneumonia deaths were recorded. The study found that participants who had engaged in 150 minutes a week of moderate intensity equivalent physical activity, such as jogging, walking or brisk walking, and two or more muscle-strengthening sessions a week had a 48% lower risk of dying from the flu or pneumonia than those who were physically inactive.

“In this large US cohort, adults who met the aerobic and muscle-strengthening physical activity guidelines were about half as likely to die from influenza and pneumonia as their peers who met neither guideline,” the authors wrote. “Relative to those who were aerobically inactive, mortality was lower in participants who performed leisure-time aerobic physical activity — even at a level below the recommended minimum of 150 MVPA min/week.”

Researchers found that adults who met only the aerobic guideline still had a 36% lower risk of death than those were physical inactive. Those who met only the muscle-strengthening guidelines were not associated with a significant difference in mortality.

From a clinical perspective, researchers said the mortality benefit associated with insufficient aerobic activity may provide additional justification for healthcare providers to encourage more physical activity in inactive patients.

“Current physical activity guidelines emphasize prevention of non-communicable diseases,” the authors wrote. “When updated, these guidelines may wish to reflect the emerging body of evidence demonstrating an association between physical activity and lower mortality from infectious diseases.”

Findings of the study were published in the British Journal of Sports Medicine.