Exogenous ketosis increases blood and muscle oxygenation but not performance during exercise in hypoxia

Available evidence indicates that elevated blood ketones are associated with improved hypoxic tolerance in rodents. From this perspective, we hypothesized that exogenous ketosis by oral intake of the ketone ester (R)-3-hydroxybutyl (R)-3-hydroxybutyrate (KE) may induce beneficial physiological effects during prolonged exercise in acute hypoxia. As we recently demonstrated KE to deplete blood bicarbonate, which per se may alter the physiological response to hypoxia, we evaluated the effect of KE both in the presence and absence of bicarbonate intake (BIC). Fourteen highly trained male cyclists performed a simulated cycling race (RACE) consisting of 3-h intermittent cycling (IMT180') followed by a 15-min time-trial (TT15') and an all-out sprint at 175% of lactate threshold (SPRINT). During RACE, fraction of inspired oxygen ([Formula: see text]) was gradually decreased from 18.6% to 14.5%. Before and during RACE, participants received either 1) 75 g of ketone ester (KE), 2) 300 mg/kg body mass bicarbonate (BIC), 3) KE + BIC, or 4) a control drink in addition to 60 g of carbohydrates/h in a randomized, crossover design. KE counteracted the hypoxia-induced drop in blood ([Formula: see text]) and muscle oxygenation by ∼3%. In contrast, BIC decreased [Formula: see text] by ∼2% without impacting muscle oxygenation. Performance during TT15' and SPRINT were similar between all conditions. In conclusion, KE slightly elevated the degree of blood and muscle oxygenation during prolonged exercise in moderate hypoxia without impacting exercise performance. Our data warrant to further investigate the potential of exogenous ketosis to improve muscular and cerebral oxygenation status, and exercise tolerance in extreme hypoxia.

Medienart:

E-Artikel

Erscheinungsjahr:

2021

Erschienen:

2021

Enthalten in:

Zur Gesamtaufnahme - volume:321

Enthalten in:

American journal of physiology. Regulatory, integrative and comparative physiology - 321(2021), 6 vom: 01. Dez., Seite R844-R857

Sprache:

Englisch

Beteiligte Personen:

Poffé, Chiel [VerfasserIn]
Robberechts, Ruben [VerfasserIn]
Podlogar, Tim [VerfasserIn]
Kusters, Martijn [VerfasserIn]
Debevec, Tadej [VerfasserIn]
Hespel, Peter [VerfasserIn]

Links:

Volltext

Themen:

(R)-3-hydroxybutyl (R)-3-hydroxybutyrate
Bicarbonate
Bicarbonates
Exercise performance
Hydroxybutyrates
Journal Article
Ketone
Ketone Bodies
Normobaric hypoxia
Oxygen saturation
Randomized Controlled Trial
Research Support, Non-U.S. Gov't

Anmerkungen:

Date Completed 06.12.2021

Date Revised 14.12.2021

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1152/ajpregu.00198.2021

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM332086747