Effect of Acute Grape Seed Extract Supplementation on the Heart Rate Recovery Kinetics in Individuals with High BMI

Studies have suggested that post-exercise heart rate recovery (PHRR) is a useful tool in evaluating dysfunction of autonomic nervous system. Individuals with hign BMI are characterized by heightened sympathetic out, inducing delayed HRR. Although grape seed extract (GSE) supplementation has been shown to increase nitric oxide production and decrease overactive sympathetic activity, there is limited evidence on its potential beneficial effects on PHRR. Purpose: The aim of this study was to investigate the effect of GSE supplementation on PHRR following a maximal exercise tesing using a cycle. Methods: Participants were randomly assigned via a double-blind, cross-over design to either receive GSE (300mg, 2 capsules) or PL (300mg, 2 capsules) with a washout period of at least 72 hrs. between trials. PHRR was continuously measured at 5 sec. intervals throughout the experiment for 5 minutes. The PHRR kinetics (tau) was assessed between GSE and PL. Results: Tau significantly improved following GSE supplementation (120±15 sec) compared to PL condition (141±17 sec). Conclusion: Our results indicated that GSE is effective in improving heart rate recovery kinetics in individuals with high BMI. Thus, regular treatment with GSE can provide a nonpharmacological intervention to reduce sympathetic hyperactivity in conditions where excessive sympathetic activity is consistently present.