Acute beetroot juice ingestion improves the exercise capacity of chronic obstructive pulmonary disease (COPD), according to a recent study from Wake Forest University.

COPD makes it difficult for patients to breathe and worsens over time. Patients often complain of shortness of breath with exertion, so tasks like climbing steps can leave them gasping for air. In turn, they tend to limit their activities, become more sedentary, and lose fitness and physical function.

"The intent of this study was to determine if acute ingestion of beetroot juice, which is rich with nitrates, prior to exercising could improve the exercise capacity of COPD patients," Michael Berry, who is the primary investigator and lead author of the study, said in a statement.

For the study, researchers collected data from 15 COPD patients. Patients completed four visits. During visit one, they completed baseline pulmonary function testing, filled out health status questionnaires, had a brief medical examination and completed an incremental exercise test on a stationary bicycle to determine their maximal exercise work rate. The second visit one week later consisted of additional pulmonary function and lung volume testing, as well as a familiarization exercise test on an exercise bicycle at 75 percent of the patients' previously determined maximal work rates.

Participants were assigned to one of two treatments -- beetroot juice (visit three) and placebo (visit four) or placebo (visit three) and beetroot juice (visit four). These visits were separated by at least a seven-day break.

The findings showed overall that patients who drank beetroot juice were able to extend their exercise time, and had reduced exercise diastolic and resting systolic blood pressures.

"One of the benefits of exercise is that if you get positive results, you're more likely to continue doing it. If beetroot juice positively impacts those results, it could motivate COPD patients to continue to be physically active and improve their health," Berry said.

The findings are detailed in the journal Nitric Oxide: Biology and Chemistry.