A single 25-gram dose of a ketone monoester supplement led to better reaction times following a 45 minute simulated soccer match, compared to placebo.
Scientists from the University of Western Ontario used the commercial supplement called ΔG ketone performance marketed by Orlandom, FL-based TdeltaS Global. The supplement was also associated with reduced glucose and lactate levels in the blood.
“These data suggest that [ketone monoester] supplementation can attenuate the decline in some aspects of cognitive function during sports characterized by repeated, intense, intermittent exercise,” they wrote. However, given that the study only included nine recreationally active men in a double-blind, balanced, crossover design, the researchers called for more study to assess fully “the possible cognitive/physical benefits of [ketone monoester] for athletes”.
In recent years, exogenous ketones delivered synthetically in supplement form have emerged as an easier and faster route to triggering a state of ketosis than more restrictive conventional methods.
The potential cognitive benefits of exogenous ketones were reported in a 2021 paper published in the Journal of Physiology. That study, performed by scientists at the University of British Columbia Okanagan, found that ketone supplements containing β-hydroxybutyrate led to improvements in aspects of cognition and increases cerebrovascular blood flow (CBF) in obese people.
In the sports realm, several studies have examined the potential cognitive benefits during exercise. But the results have been mixed, said the University of Western Ontario scientists.
The new study included nine recreationally active men randomly assigned to receive either the ketone monoester (KME) supplement or placebo during a simulated soccer match (SSM). The men underwent a 40-minute mental fatiguing task and then consumed the KME or placebo. This was followed by the SSM, which featured three 15-minute running periods separated by three-minute recovery periods. Cognitive tests, namely the Stroop and Choice Reaction Task (CRT), were performed throughout the simulated match. One week after this, the participants returned to the lab to cross over to the other intervention.
The data showed that ketone supplements decreased blood glucose and blood lactate levels versus placebo, which perhaps indicated a carbohydrate sparing effect, said the researchers. Increases in blood levels of beta-hydroxybutyrate were observed following ketone supplementation, but not for placebo, as would be expected.
Impairments in the CRT were observed in both ketone and placebo groups, but the impairment was significantly less in the ketone group, compared to placebo, they added. Specifically, the decline in the ketone group was 1.3%, compared to 3.4% for placebo.
The researchers did not find any other differences between the interventions for other measures of cognitive function, including on the Stroop test.
“These results should be interpreted with caution and additional study with more challenging dynamic visual acuity tasks or even with future sport video game simulation tasks using the technology now available from companies like EA is needed to confirm the present findings,” they wrote.
2022, 14(20), 4376; doi: 10.3390/nu14204376
“Ketone Ester Supplementation Improves Some Aspects of Cognitive Function during a Simulated Soccer Match after Induced Mental Fatigue”
Authors: M.D. Quinones et al.