Researchers from the Graduate School of Sport Sciences at Waseda University in Tokorozawa Japan just completed an eight-week study which looked at how a ketogenic diet may affect exercise capacity.
In their study, they found that a keto diet can increase exercise capacity, and they also attempted to explain the mechanisms through which that increase may take place.
How the Study Was Done
The researchers used mice for their eight-week study. Mice are often used for this type of research because of their genetic and biological similarities to humans. It’s also easy to place strict controls on the diet and behavior of mice, which allows researchers to observe results for the specific variables they are studying.
For this study, 35 mice were divided into four groups:
- A control group fed standard mouse chow with the encouragement of sedentary behavior
- A group fed chow with exercise provided
- A group fed a ketogenic diet with sedentary behavior encouraged
- A group fed a ketogenic diet with exercise provided
All four groups were allowed to eat as much of their provided diet as they desired.
Exercise capacity was evaluated by running performance on a treadmill, measured at the beginning and end of the study.
The researchers also monitored several of the mice’s blood biomarkers and analyzed changes in their calf muscle fibers.
What the Study Found
Both groups of mice fed the ketogenic diet had better exercise endurance than the other two groups. The chow-fed mice averaged 243 minutes of treadmill run time while the ketogenic diet-fed mice averaged 289 minutes — an approximate 19% difference.
Through their analysis of biomarkers and muscle changes, the researchers also found that the mice on the ketogenic diet were much more efficient at utilizing stored fatty acids for energy and that their muscles showed less exercise-induced damage than their chow-fed peers.
The researchers summarized their conclusions by saying, “results revealed that an eight-week KD may: (1) enhance exercise performance by up-regulating ketolysis and FAO ability, and (2) have potential to prevent muscle damage by altering the IL-6 secretion profile. Therefore, a KD may be a promising diet approach for endurance sports and injury prevention.”
The researchers clearly found increased exercise capacity in the ketogenic diet-fed mice. They went one step further in an attempt to understand why this increased capacity occurred.
Their research indicated that the mice in the ketogenic groups became much more efficient at utilizing fatty acids during the eight-week study, saying, “that mechanism involved in this response may be enhanced lipolysis and ketolysis.” (“Lipolysis” is the breakdown of fats into fatty acids and “ketolysis” is the production and utilization of ketone bodies.)
While results from mice studies don’t always transfer into similar results in humans, this study does provide some interesting information which adds to the ongoing discussion about the keto diet’s effects on athletic performance.
You can review details of the full study here.