Cocoa-flavanols enhance moderate-intensity pulmonary V̇O2 kinetics but not exercise tolerance in sedentary middle-aged adults

Sadler, Daniel and Draijer, Richard and Stewart, C.E. and Jones, Helen and Marwood, Simon and Thijssen, Dick (2021) Cocoa-flavanols enhance moderate-intensity pulmonary V̇O2 kinetics but not exercise tolerance in sedentary middle-aged adults. European Journal of Applied Physiology. ISSN 1439-6319

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Abstract

Introduction: Cocoa flavanols (CF) may exert health benefits through their potent vasodilatory effects, which are perpetuated by elevations in nitric oxide (NO) bioavailability. These vasodilatory effects may contribute to improved delivery of blood and oxygen (O2) to exercising muscle. Purpose: Therefore, the objective of this study was to examine how CF supplementation impacts pulmonary O2 uptake (V̇O2) kinetics and exercise tolerance in sedentary middle-aged adults. Methods: We employed a double-blind cross-over, placebo-controlled design whereby 17 participants (11 male, 6 female; mean±SD, 45±6 years) randomly received either 7 days of daily CF (400 mg) or placebo (PL) supplementation. On day 7, participants completed a series of ‘step’ moderate- and severe-intensity exercise tests for the determination of V̇O2 kinetics. Results: During moderate-intensity exercise, the time constant of the fundamental phase II V̇O2 kinetics (τV̇O2) was decreased by 15% in CF as compared to PL (mean±SD; PL: 40±12 vs. CF: 34±9 s, P=0.019), with no differences in the amplitude of V̇O2 (AV̇O2; PL: 0.77±0.32 vs. CF: 0.79±0.34 l min−1, P=0.263). However, during severe-intensity exercise, τV̇O2,the amplitude of the slow component (SCV̇O2) and exercise tolerance (PL: 435±58 vs. CF: 424±47 s, P=0.480) were unchanged between conditions. Conclusions: Our data show that acute CF supplementation enhanced V̇O2 kinetics during moderate-, but not severe-intensity exercise in middle-aged participants. These novel effects of CFs, in this demographic, may contribute to improved tolerance of moderate-activity physical activities, which appear commonly present in daily life.

Item Type: Article
Additional Information and Comments: This version was accepted for publication in The European Journal of Applied Physiology. The final, published version is available Open Access at https://link.springer.com/article/10.1007/s00421-021-04682-9
Keywords: Flavanols · Oxygen uptake kinetics · Heart rate · Exercise tolerance · Middle-age
Faculty / Department: Faculty of Science > School of Health Sciences
Depositing User: Simon Marwood
Date Deposited: 25 May 2021 09:06
Last Modified: 25 May 2021 09:06
URI: https://hira.hope.ac.uk/id/eprint/3288

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