Hey Chuggington,
So, what is meant by "performance" here is very important.
Here's some info - an important rabbit hole - I went down based on the first half of the first video below.
Chaffey mentions Tim Noakes, who wrote a recent special communication here) ("
[font=AdvTTe0754e31.B]Ketogenic Diets Are Beneficial for Athletic Performance"[/font]:
https://asobi-plus.jp/wp-content/uploads...に有益である.pdf
In this he references the work of Coyle showing that glycogen use was the same with or without carb supplementation during high intensity endurance exercise, but those given carbohydrate were able to exercise for 1 hour longer (4 vs. 3 hr), and seems to FULLY miss the notion put forth by Coyle that in those circumstances, where supplemental carbohydrate is available at the time of glycogen depletion (and insulin levels are elevated, which will help with glucose uptake) that exercise at this higher intensity (71% VO2 max) BECAUSE the carbohydrate is able to provide ATP at the rate needed to support exercise at that intensity. (Noakes seems to be claiming the carbs are only to maintain euglycemia, and seems to miss the point that glucose levels don't necessarily indicate flux through blood glucose oxidative pathways.)
Chaffee also notes in that video that fats (and ketones) can be rapidly used to replenish glycogen (seemingly implying that a keto diet would mean faster glycogen replenishment), citing a Hungarian (a conversation with him) researcher who claims this, but provides no evidence to this effect. This runs counter to any research i've seen where a control group was used or carbohydrate was not permitted and glycogen levels stay essentially unchanged without incoming glucose. (There can be some conversation of lactate to glycogen, and of course gluconeogenesis could slowly raise glycogen levels such that someone who is regularly exercising on a carb devoid diet might have above low levels but not zero glycogen.)
I couldn't find the story of untrained guy who ran 5 marathons without eating anything. I imagine he didn't run very fast, in part b/c of the lack of carbs, but his training status was the main determinants of course. The decent body of literature on fat adaptations demonstrates that training performance decline such that any increased / trained ability to utilize fats is offset by a detraining d/t lack of training intensity when eating a VL carbohydrate diet.
(Sorry, all for now. I'd be happy to answer specific questions, but I just don't have time to review any and everything thing in all of those videos. Too much to respond to.)
-S
(09-09-2024, 12:58 AM)Chuggington808 Wrote: This is one of the main guys… Dr Chaffee his whole YouTube channel is about how his performance and others have improved athletic performance and even reverse diseases. I understand genetics play a lot of roles and these type of phenomena. His videos are fairly long, but he also has a lot of clips on his YouTube channel that sum up his videos.
https://youtu.be/4rBt91jZNPU?feature=shared
https://youtu.be/PtK6IY_G5g4?feature=shared
https://youtube.com/shorts/Xp_jkbhbis4?feature=shared
