Cocoa flavanols improve peakVO₂and exercise capacity in a randomized double blinded clinical trial in healthy elderly

Abstract

Background: Loss of functional capacity and redox signaling is one of the hallmarks in cardiovascular aging. Cocoa flavanols (CF) exert favorable effects on endothelial function, blood pressure, and inflammation. These cardiovascular health markers worsen with increasing age and limit functional exercise capacity. Aim: To investigate the effect of CF on cardiorespiratory-fitness in healthy elderly. Methods: In a randomized, double-masked, placebo-controlled, parallel-group dietary intervention trial, 68 healthy elderly (55-79 years, 28 female) received either 500 mg of CF or a nutrient-matched control capsule twice a day for 30 days. Primary endpoint was defined as peak oxygen consumption (VO2) in a cardiopulmonary exercise test (CPET). Secondary endpoints were oxygen pulse (VO2/heart rate (HR)), resting blood pressure (BP), and resting vascular function. Results: After 30 days of CF intake peakVO2 increased by 190 ml/min (95% CI 1-371 ml/min) and peakVO2/kg by 2.5 ml/ (min*kg) (95% CI 0.30-4.2 ml/ (min*kg)). O2-pulse increased by 1.7 ml (95% CI 0.29-3.2 ml) and max exercise capacity by 9.6 W (95% CI 2.1-17.7 W). CF decreased resting systolic and diastolic BP by 5.4 mmHg (95% CI -10.7 - -0.1 mmHg) and 2.9 mmHg (95% CI (-) 5.5-(-) 0.4 mmHg), respectively. Flow-mediated vasodilation (FMD) increased by an absolute 1.3% (95% CI 0.76-1.79 %) in the CF group. Indexes of pulmonary function were not affected. No changes for primary and secondary endpoints were detected in control. Conclusion: CF substantially improve markers of cardiorespiratory fitness in healthy elderly humans highlighting their potential to preserve cardiovascular health with increasing age.