Sebastian Clauss, Johannes Scherr, Alan Hanley, Jens Schneider, Ina Klier, Korbinian Lackermair, Eva Hoster, Michael Vogeser, David C. Nieman, Martin Halle, Thomas Nickel. Impact of polyphenols on physiological stress and cardiac burden in marathon runners – results from a substudy of the BeMAGIC study. Applied Physiology, Nutrition, and Metabolism 10.1139/apnm-2016-0457.
Both physiologic stress and chronic heart disease are associated with increased systemic levels of chromogranin A (CGA) and NT-proBNP. Marathon running causes physiological stress and imposes a significant cardiac burden. Polyphenol-rich Mediterranean and Asian diets have been demonstrated to exert beneficial effects on the cardiovascular system. In this study we investigated whether pretreatment with a polyphenol beverage could attenuate the physiological and cardiac stress associated with a marathon.
In the BeMaGIC trial 277 athletes were randomized into two groups in a double-blinded fashion receiving 1-1.5 L/day of the same beverages either with (study beverage) or without (placebo) polyphenol enrichment (about 400 mg of gallic acid equivalents per day of a complex mixture of polyphenols).Blood samples were taken three weeks before (V1), one day before (V2), and immediately (V3), 24 hours (V4) and 72 hours (V5) after running a marathon. In our current sub-study CGA and NT-proBNP levels were analyzed by ELISA in the fastest 18 and the slowest 22 runners.
CGA and NT-proBNP levels increased significantly after the marathon (V3) and returned to baseline 72 hours after the marathon (V5). Neither CGA nor NT-proBNP differed significantly between athletes receiving study beverage versus placebo. Separating our cohort into fast and slow runners did not reveal any significant difference regarding CGA or NT-proBNP levels between groups.
Our study provides no evidence that polyphenol supplementation attenuates marathon running induced physiological stressor cardiac burden in fast or slow runners.