Background

It has been hypothesized that oral ketones may enhance endurance performance even in people not on a keto diet by providing the body with an alternative fuel source.

The study

In this crossover trial, 8 endurance runners tested a combination of carbs and ketone esters (60 g + 40 g) against carbs alone (60 g + placebo). The endpoints were blood ketone levels, cognitive performance, and a timed trial (10 km / 6.2 miles).

The results

While the “carb + ketone” group saw their blood ketone levels reach 1.0–1.3 mmol/L, no statistical or meaningful difference was seen between groups for timed trial or cognitive performance.

Note

This crossover trial adds itself to a growing list of controlled trials that found no endurance-performance benefit from oral ketones.[1][2][3][4][5][6][7]

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This Study Summary was published on September 4, 2020.

References

  1. ^Pete J Cox, Tom Kirk, Tom Ashmore, Kristof Willerton, Rhys Evans, Alan Smith, Andrew J Murray, Brianna Stubbs, James West, Stewart W McLure, M Todd King, Michael S Dodd, Cameron Holloway, Stefan Neubauer, Scott Drawer, Richard L Veech, Julian L Griffin, Kieran ClarkeNutritional Ketosis Alters Fuel Preference and Thereby Endurance Performance in AthletesCell Metab.(2016 Aug 9)
  2. ^Trevor O'Malley, Etienne Myette-Cote, Cody Durrer, Jonathan P LittleNutritional ketone salts increase fat oxidation but impair high-intensity exercise performance in healthy adult malesAppl Physiol Nutr Metab.(2017 Oct)
  3. ^Jill J Leckey, Megan L Ross, Marc Quod, John A Hawley, Louise M BurkeKetone Diester Ingestion Impairs Time-Trial Performance in Professional CyclistsFront Physiol.(2017 Oct 23)
  4. ^Mark Evans, Ella Patchett, Rickard Nally, Rachel Kearns, Matthew Larney, Brendan EganEffect of acute ingestion of β-hydroxybutyrate salts on the response to graded exercise in trained cyclistsEur J Sport Sci.(2018 Apr)
  5. ^Hunter S Waldman, Steven A Basham, Ffi G Price, JohnEric W Smith, Harish Chander, Adam C Knight, Ben M Krings, Matthew J McAllisterExogenous ketone salts do not improve cognitive responses after a high-intensity exercise protocol in healthy college-aged malesAppl Physiol Nutr Metab.(2018 Jul)
  6. ^David J Dearlove, Olivia K Faull, Edward Rolls, Kieran Clarke, Pete J CoxNutritional Ketoacidosis During Incremental Exercise in Healthy AthletesFront Physiol.(2019 Mar 29)
  7. ^Philip J Prins, Andrew P Koutnik, Dominic P D'Agostino, Christopher Q Rogers, Jacob F Seibert, Jillian A Breckenridge, Daniel S Jackson, Edward J Ryan, Jeffrey D Buxton, Dana L AultEffects of an Exogenous Ketone Supplement on Five-Kilometer Running PerformanceJ Hum Kinet.(2020 Mar 31)