Drink Your Beets: Improving Exercise Endurance in HFpEF
Study Questions:
Does a relatively low single dose or a week-long dosage of dietary inorganic nitrate improve exercise tolerance in patients with heart failure with preserved ejection fraction (HFpEF)?
Methods:
This was a pilot study of 20 HFpEF patients enrolled in an initial crossover design comparing a single, acute dose of beetroot juice (BRJ) to a nitrate-depleted placebo BRJ. Following the last crossover visit, there was a second phase of 1 week of daily doses for an average of 7 days. The primary outcome was submaximal aerobic endurance, measured as cycling time to volitional exhaustion at 75% of measured maximal power output.
Results:
No adverse events were associated with the intervention. With a single acute dose of BRJ, there were no differences in the primary outcome of submaximal aerobic endurance, but with 1 week of daily doses, there was a significant increase (BRJ: 449 ± 180 seconds vs. placebo: 363 seconds ± 125 seconds; 24% increase; p = 0.02). With 1 week of daily doses, systolic blood pressure was significantly reduced at rest (120 ± 13 mm Hg vs. 134 ± 14 mm Hg, respectively; p < 0.001).
Conclusions:
In this pilot study of elderly HFpEF patients, 1 week of daily dosing with BRJ (6.1 mmol inorganic nitrate) significantly improved submaximal aerobic endurance and blood pressure.
Perspective:
Albeit limited by a small sample size, this is an important and creative study that suggests the benefits of BRJ in improving aerobic endurance and lowering systolic blood pressure among elderly patients with HFpEF, an increasingly prevalent problem, particularly in the older population. With limited therapeutic options to treat HFpEF, BRJ may offer a convenient option with few (if any) side effects. Further study is necessary to confirm and clarify the magnitude of effect.
Keywords: Aged, Blood Pressure, Blood Pressure Determination, Exercise, Exercise Tolerance, Geriatrics, Heart Failure, Nitrates, Secondary Prevention, Stroke Volume
< Back to Listings