AUTHOR=Clark Daniel , Munten Stephanie , Herzig Karl-Heinz , Gagnon Dominique D. 

TITLE=Exogenous Ketone Salt Supplementation and Whole-Body Cooling Do Not Improve Short-Term Physical Performance

JOURNAL=Frontiers in Nutrition

VOLUME=8

YEAR=2021

URL=https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2021.663206

DOI=10.3389/fnut.2021.663206

ISSN=2296-861X

ABSTRACT=<p>Exogenous ketone supplementation and whole-body cooling (WBC) have shown to independently influence exercise metabolism. Whether readily available ketone salts, with and without WBC, would provide similar metabolic benefits during steady-state aerobic and time-trial performances was investigated. Nine active males (VO<sub>2peak</sub>: 56.3 ± 2.2 mL·kg<sup>−1</sup>·min<sup>−1</sup>) completed three single-blind exercise sessions preceded by: (1) ingestion of placebo (CON), (2) ketone supplementation (0.3 g·kg<sup>−1</sup> β-OHB) (KET), and (3) ketone supplementation with WBC (KETCO). Participants cycled in steady-state (SS, 60% <italic>W</italic><sub>max</sub>) condition for 30-min, immediately followed by a 15-min time trial (TT). Skin and core temperature, cardio-metabolic, and respiratory measures were collected continuously, whereas venous blood samples were collected before and after supplementation, after SS and TT. Venous β-OHB was elevated, while blood glucose was lower, with supplementation vs. CON (<italic>p</italic> &lt; 0.05). TT power output was not different between conditions (<italic>p</italic> = 0.112, CON: 190 ± 43.5 W, KET: 185 ± 40.4 W, KETCO: 211 ± 50.7 W). RER was higher during KETCO (0.97 ± 0.09) compared to both CON (0.88 ± 0.04, <italic>p</italic> = 0.012) and KET (0.88 ± 0.05, <italic>p</italic> = 0.014). Ketone salt supplementation and WBC prior to short-term exercise sufficiently increase blood β-OHB concentrations, but do not benefit metabolic shifts in fuel utilization or improve time trial performance.</p>