Published: Journal of Physiology, 2019 

Background: In order for athletes to improve, they need to push their bodies. However, it’s common for athletes to push their bodies too hard during training, leading to a counterproductive state in which muscles breakdown. This is called “overtraining.” Ketones protect muscles from breaking down, suggesting that ketones could protect against “overtraining.”

Results: Fit male athletes were given either ketone ester or a control drink following intense endurance exercise training, twice per day six days per week for three weeks. The ketone drink improved hormonal and metabolic markers of overtraining and, at the end of the three weeks, the athletes that received the ketone ester demonstrated significantly better endurance exercise performance as compared to the control group.