Ketogenic Diets

[Adam Rosner]

I've been on a keto diet now for about a month and I wanted to come here and see if anyone else has tried this. For the last year I was trying to lift weights and put a little weight on (almost all muslce), but as a result I also lost touch with what "fitness" means..I'm talking about bodybuilding vs crossfit.

Well I discovered the ketogenic diet (CKD) - 65%fat, 30-35% pro, 0-5% carb around Christmas time, and had been toying around with it. Over the last 2 months I've rekindled my love for crossfit/running and have been using the keto diet on top of that. Man, my energy has been through the roof! I'm eating 2-3 times a day, and never hungry. I find that I never run out of steam for the WOD, and at the same time I'm just unstoppable on my runs.

There are a few cons to this diet...every weekend or so I have to do a carb-up where my marcros are reversed (65%carbs, 30% pro, 0% fat) to replenish glycogen stores and that always makes me feel like crap for a day...though it is a heck of a day carbing up like that.

Anyway, I know that previous to this I was a zone guy, but I have to admit that I did not feel THIS good on the zone. I will always give full respect to the Zone diet but I have to say that keto seems to be for me. Any thoughts?

[Matt DeMinico]

You're shooting yourself in the foot on the weekends "carbing up". Your body will take a few weeks at least to adjust, but you can live on literally zero carbs (well, everything has some carbs in it, even meat, but very little carbs...) But if you have zero carbs for 5 days, then eat a ton of them on the weekends, you're stopping that change from happening.

[Trampas Hutches]

I have not had any experience with the Keto diet but I good friend of mine is having to put their 6 yo on it. He has epilepsy and medication is not helping the seizures at all. Apparently this diet has a high success rate of keeping people seizure free. It is tedious process though, poor guy has to "detox" and learn the diet while in the hospital since it can be really dangerous for kids. Just a tidbit.

[Scott Allen Hanson]

Originally Posted by Matt DeMinico

You're shooting yourself in the foot on the weekends "carbing up". Your body will take a few weeks at least to adjust, but you can live on literally zero carbs (well, everything has some carbs in it, even meat, but very little carbs...) But if you have zero carbs for 5 days, then eat a ton of them on the weekends, you're stopping that change from happening.

No question you can live on literally zero carbs as Matt says (e.g., the Inuit) and continue to perform well in WOD's that are mostly utilizing oxidative (i.e., "aerobic") metabolism, but if you do not replenish muscle glycogen (carb up), you would likely see a decline in performance for high intensity work like sprinting and low-rep lifting. If this area of performance is of little importance, then you could definitely continue the ketogenesis 24/7. It may actually be healthier in the long run. Just depends on your priorities.

[Joe Waguespack]

Just my experiences with it brother,

I am training a MMA fighter who came to me on a Keto diet since he was trying to cut weight for an upcoming fight. He was tired all the time and just looked bad. He is the type of guy that is VERY detailed and will read everything and do everything to the letter and make sure every little detail is correct before he proceeds with something. So I'm pretty sure he was following his Keto diet correctly. I talked him into trying the Zone for two weeks to see what happens. He was a little hesitant but tried it out, since we have some time to play with before his fight. He dropped 7 lbs in two weeks and looks like he has filled out , he is vascular and has muscle definition he didn't have before, and his performance and strength in his WOs with me and in his fight training has skyrocketed. At first I figured the re-introduction of carbs was the reason for the immediate changes (kind of like when a bodybuilder carbs up right before a contest), but we are five weeks in right now and the weight keeps coming off and the performance and strength keep improving. Thats a recent experience of mine with the Keto diet. Hope it gives some insight.

[Matt DeMinico]

Originally Posted by Scott Allen Hanson

No question you can live on literally zero carbs as Matt says (e.g., the Inuit) and continue to perform well in WOD's that are mostly utilizing oxidative (i.e., "aerobic") metabolism, but if you do not replenish muscle glycogen (carb up), you would likely see a decline in performance for high intensity work like sprinting and low-rep lifting. If this area of performance is of little importance, then you could definitely continue the ketogenesis 24/7. It may actually be healthier in the long run. Just depends on your priorities.

I disagree. You're basing the glycogen replenishment rate on people who are used to carbs, all of a sudden stop eating them, and then measure their muscle glycogen levels. That's a wholly different story than having someone who's used to a ketogenic diet, has adjusted for a period of time to where their body is adapted to it, and then goes and does something like a WOD 5-6 days a week. THAT person would most likely (I believe anyhow) be perfectly fine and ahve no issues with glycogen stores, because their body has kicked in the necessary mechanisms to get tons of energy from fat whenever necessary.

I've heard testimonials from people who eat almost zero carbs, and they constantly have a stable blood glucose level. They've done 12 hour fasts for blood tests, and they test their blood sugar and it comes back as a result of basically "dude, your blood sugar level shows you just ate about 4 hours ago..." to which they reply, no, I haven't eaten in 15 hours.

http://www.biblelife.org/myths.htm (w/f safe) - scroll down to Myth #2, specifically the fourth paragraph about the 12-hour fast. Note, the author has some poor reasoning on some of the topics, and I don't agree with all their nutritional info, but their evidence of the 12 hour fast while on a carb-restricted diet is good data.

[Scott Allen Hanson]

You might be interested in this study from Nutrition and Metabolism (WFS):

http://www.nutritionandmetabolism.com/content/1/1/2

Particularly note the conclusion, which is also stated elsewhere in the report:

Conclusions
Both observational and prospectively designed studies support the conclusion that submaximal endurance performance can be sustained despite the virtual exclusion of carbohydrate from the human diet. Clearly this result does not automatically follow the casual implementation of dietary carbohydrate restriction, however, as careful attention to time for keto-adaptation, mineral nutriture, and constraint of the daily protein dose is required. Contradictory results in the scientific literature can be explained by the lack of attention to these lessons learned (and for the most part now forgotten) by the cultures that traditionally lived by hunting. Therapeutic use of ketogenic diets should not require constraint of most forms of physical labor or recreational activity, with the one caveat that anaerobic (ie, weight lifting or sprint) performance is limited by the low muscle glycogen levels induced by a ketogenic diet, and this would strongly discourage its use under most conditions of competitive athletics.

In general, this study (actually report and analysis of two studies) supports what I stated earlier, that ketogenic diets do not adversely impact endurance/aerobic capacity, but are likely to adversely impact activities like sprinting and heavy weight-lifting.