I'm in! -or- What the hell is wrong with me?
So I started Keto yesterday and yeah, not bad, I've been in Ketosis before. Besides, the food is awesome, right? I had bacon for breakfast and I haven't had bacon in like 5 years.
Oh bacon, how I have missed you.
Then we went for our lunchtime ride. I had been kind of worried about this so I ate a huge bowl of spinach and 6 oz of ribeye 45 minutes before the ride. On the ride I felt pretty awesome. I brought a gel along in case I felt bonky but strangely I didn't, I felt awesome. I was the hammer. Oddly, I was able to hold a higher heart rate before my breathing got all erratic (no idea if that's from Keto or just oddity) and I never felt bonky or tired. Normally around 800kj into a ride I feel like crap but this time I didn't and I'm wondering the whole time what is wrong with me. It was an 1100Kj ride which equates pretty much 1:1 with calories so I was really worried I was going to pass out afterward. I was a little lightheaded but no problem. Came home, made some keto thai soup and pissed on a ketostick and woohoo, in ketosis in 24 hours. Burning all your glycogen on a bicycle will do that.
The whole reason for doing this is to strip 25 lbs of fat off my frame so when bike racing season rolls around again I can actually climb mountains at a decent speed instead of slow speed. Based on all the before and after pics in r/keto of guys who went from flabby to ripped, it'll work. Anyhow, thanks for letting me rant.
(Note: the link to my ride file won't work this evening from like 9-11 mst because the site is going down for upgrades).
Posted Nov 11, 2011, 3:13 AM UTC
It can take up to three weeks for your muscle to adapt and stop using ketones when glucose is sparse, it might be that if you do intense exercise the energy need of the muscle will surpass the amount of ketones being created, and I'm guessing you could get the same "bonk" (but I can't really verify that):
"The Ketogenic Diet" by Lyle McDonald, page 46/47.
After that period your performance is limited by the available fatty acids and not ketones (ketones are made from fatty acids, mostly, by your liver). The definite time it takes to adapt might vary, but a study over six weeks show that people can still increase their endurance on Keto during that time frame:
...
Phinney SD, et al. "Capacity for Moderate Exercise in Obese Subjects after Adaptation to a Hypocaloric, Ketogenic Diet" J Clin Invest. 1980 November; 66(5): 1152–1161.
Looking at another keto endurance study in well-trained cyclists shows an increase at the fourth week of keto (EBD = eucaloric balanced diet, EKD = eucaloric ketogenic diet, EKD-4 = week four of keto):
and..
..
Phinney SD, et al. "The human metabolic response to chronic ketosis without caloric restriction: preservation of submaximal exercise capability with reduced carbohydrate oxidation". Metabolism. 1983 Aug;32(8):769-76.
Lyle McDonald: That guy's about one ketone-body away from complete insanity, lol. But when it comes to ketogenic diets and bodybuilding, he knows his science to a fault.
Thanks for this. I'm curious how it'll affect my riding over the next few weeks. I'm doing a bunch of long medium hard rides this weekend including a lot of time climbing at altitude so we'll see what happens.
If muscles stop deriving energy from ketone bodies after the third week then how do they derive energy? Or do they just not? I didn't think muscles could directly use fatty acids.
Joe Friel advocates a paleo diet and a bunch of his athletes have had good luck with it and endurance sports although I think there's a bit more carbs in his and a little bit of carbs before workouts as opposed to none. I can't race in this deprived state but it's wintertime, it's all base miles anyhow (Zone 2) and I can do that carb deprived.
Exercise isn't something I've focused my reading on, but this is roughly how I've understood it.
The "real" energy your muscles run on is ATP, and your body has three ways of generating it: creatine phosphate (anaerobic fast, 10-20 seconds of energy), glucose (anaerobic fast, 1-2 minutes of energy, as well as aerobic slow 2-10 minutes) and fat (aerobic slow, 10+ minutes). Depending on your diet, training and genetics (muscle fiber types) the different pathways are affected differently. Creatine supplementation helps with weight lifting as you have a larger store of creatine phosphate which allows you to lift weights longer and/or with more intensity. Eating carbs increases your glycogen stores and similarly allows you to gain more ATP from the glycolytic pathway.
The problem with both creatine and glucose is that the stores are rather small (compared to your fat reserves), you have ~100 grams of liver glycogen and ~350g of muscle glycogen (training increases your stores and post-workout supercompensation can temporarily give you ~180% capacity) which doesn't last long in endurance events if you don't properly burn fat. When glycogen runs out and you can't generate more through gluconeogenesis your blood sugar drops and you "bonk" (no energy for your brain or muscles). Fat stores are closer to "infinite", but the problem with the large fat stores is throughput. Creatine and glucose are readily available in the muscle and you can push hard as you can tap them fast, fat stores are slower to mobilize (you don't have high in-muscle reserves for endurance, so you need to get them from elsewhere) and on top of that you are limited by your mitochondrial capacity (the part of your cells that generate ATP from fat) to oxidize the fat you supply (and how good you can supply oxygen).
With endurance training you increase size of your type I muscle fiber (the fat burning type) and training with high fat/low carb diets increases mitochondrial biogenesis as well as the mitochondrial capacity for fat oxidation. All this helps to provide more ATP for exercise, but it takes some time to adapt (probably depends on how your diet looked before, and your genes):
...
And it seems like the change should come after just a few days to a week:
Galgani JE, Moro C, Ravussin E. "Metabolic flexibility and insulin resistance" Am J Physiol Endocrinol Metab. 2008 Nov;295(5):E1009-17. Epub 2008 Sep 2.
So, from what I've gathered you'll have more reserves to tap from with Keto, but you can run into problems with the more intense parts where you need to have a higher amount of energy available. If it becomes a problem that you simply can't push as hard as you need to you can try and add some strength training to increase the capacity of you muscle (endurance only didn't do that in this study):
SE = Strength + Endurance training.
Aagaard P, et al. "Effects of resistance training on endurance capacity and muscle fiber composition in young top-level cyclists" Scand J Med Sci Sports. 2011 Mar 1. doi: 10.1111/j.1600-0838.2010.01283.x. [Epub ahead of print]
Thank you for taking the time to write this well thought out reply. It kind of sucks on reddit that when you take the time to give a reply like this you get relatively few upvotes, but flippant responses seem to generate tons.
I work in the endurance training industry and while it's great, relatively little credence is given to non carbohydrate diets. Joe Friel and Lynn Cordain promote the paleo thing and I may end up there after I get my fat stores down to where I want them but right now Keto is working.
On my ride yesterday I felt "okay" but not strong, although I had some lingering muscle soreness from the ride the day before that was contributing to that. I couldn't really drop the hammer but riding in zone 2 was not a problem, I felt like I could have done it all day. More riding today and tomorrow, we'll see how I feel.
Karma is pretty pointless. ;)
Paleo seems like a good "long term" way of eating, I'm guessing from what I've seen that we didn't spend all our time in Ketosis, it seems more like a response to a situation where we might need to go long stretches with little carbs (or food) - like winter, droughts or just other periods of low availability of food (I have seen zero studies on this tho, so just take it as speculation). So Keto is probably not a bad thing, conversely a moderate carb diet isn't a bad thing either. If people feel good in Keto they can probably do it as long as they want (there's no good lifetime studies on Keto for long term use, so we don't know), if people don't feel good on Keto the can do regular "carby" diets. The only bad thing is most likely diets high in refined carbs and sugars.
Submit a post when you've been on Keto for a while (3-4 weeks) with an update and tell us how it went, I'm sure more people than just me are interested in how Keto performs for endurance tasks when you're fully adapted.