A paper done by many of the big names in keto and exercise:
https://academic.oup.com/edrv/advance-article/doi/10.1210/endrev/bnaf038/8432248
A discussion of it: This is youtube
https://www.youtube.com/live/NwtmRcLKO_I
I listened to it via a podcast by Metabolic Mind.
They said there are many high carb athletes who are eating too many carbohydrates and getting pre-diabetes. Andrew met one person who was obese and running a marathon every other week. Ate super high carb.
They theorize that the negative effects aren’t “bonking” (lack of muscle glycogen) but instead lowered blood sugar to the BRAIN. Yes, the brain. Apparently, it can’t run solely on ketones. They address “exercise-induced hypoglycemia (EIH)”, lowered blood sugar, which affects the brain.
They said studies have indicated that small amounts of carbs can benefit keto folks during exercise. They did not discuss this further, however, which is too bad. I commonly jog or do body weight training for about an hour with no negatives I can tell. Does it take longer than this? Are they measuring “performance” and I would “perform” better if I ate some carbs during exercise? When would I have to eat carbs and how much?
Maybe this is in the paper. Will take a while to read it though.
In the podcast, they kept referring to 100 pages for the paper. The one I downloaded, however, is 38 pages of text, and the rest of the pages are devoted to references – 602 of them. 53 pages total.