Kevin –
Indeed the data on high fat diet (HFD) and keto diet in endurance athletes is growing.
Sounds like you’re enjoying the weight loss you’re seeing on a HFD. Agreed that one must burn fat to lose weight as an athlete. A weight loss of 1-2 lbs per week is considered a healthy rate that will not compromise your training.
When you mention the benefits of fat burning on endurance races, mixed data indicate genetics, gender, and other factors determine success, whereas carbohydrates consistently show efficacy,
Carbs are needed for high intensity/race performance and for really getting maximum watts out of your body. Muscles still work on glycogen, and recent data show that fat-based diets “…do not improve training capacity or performance, but directly impair rates of muscle glycogenolysis and energy flux, limiting high-intensity ATP production”. Also “When highly trained athletes compete in endurance events lasting up to 3 h, CHO-, not fat-based fuels are the predominant fuel for the working muscles; CHO, not fat, availability becomes rate limiting for performance.”
I’d love to learn more about your comment “Once you eat carbs then your body doesn’t want to go back to burning fat for a week and it messes up my system”. It could be the type of carbs you’re choosing, and when you’re eating them. I have a very fueling-based approach to carbs, and am not a proponent of ‘just eat a high-carb diet’.
In addition, HFD/keto excludes all plant compounds important for recovery, microbiome, etc. Polyphenols (incl flavonoids & anthocyanins) help lessen oxidative damage. Keto excludes the fruits and vegies that have polyphenols important for recovery, strong microbiome, etc. I’d love to hear if you are integrating fruits and vegies into your diet.
I do like your comment “Right now I can burn fat for energy. I hope as I lean out that carbs will become a more important part of the diet” – this sounds like a reasonable approach, with some caveats (ie when in the season you’re fat-burning – off season? And which carbs and when, so you avoid putting the weight back on).
I also would like to learn more about your blood biomarkers; how are your lipid profiles looking? We want to make you a health person as well as a fast bike racer!
Thanks for contributing to the forum!
Coach Dr. Lauren