Beet Juice Boosts Muscle Power in Heart Patients (audio) Washington University School of Medicine Share Print E-Mail Loading audio... Caption Scientists have evidence that Popeye was right: Spinach makes you stronger. But it's the high nitrate content in the leafy greens -- not the iron -- that creates the effect. Building on a growing body of work that suggests dietary nitrate improves muscle performance in many elite athletes, researchers at Washington University School of Medicine in St. Louis found that drinking concentrated beet juice -- also high in nitrates -- increases muscle power in patients with heart failure. Credit Jim Dryden Usage Restrictions None Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.