I have a friend who keeps bonking and racing for crap. He is eating a very low carbohydrate diet that he heard about via Crossfit.
Is there any sort of exercise physiology evidence that eating this sort of diet somehow makes your body metabolize fat doing intense exercise? It sure isn’t doing this guy any favors.
Not enough information in this post to be helpful. Perhaps have HIM post, with additional information, such as race distance, what he eats, etc. and he might get some useful guidance.
Not enough information in this post to be helpful. Perhaps have HIM post, with additional information, such as race distance, what he eats, etc. and he might get some useful guidance.
I was using him as an example of my larger question. He is eating something like 50g of carbohydrate and training hard to race as a cat II.
Setting my friend aside, is there evidence that points to this diet making such a significant metabolic change that a high performance athlete is able to keep from running out of glycogen w/o ingesting carbs during exercise over say 3 hours at a high intensity?
Here is a scientist:
https://www.youtube.com/watch?v=BMOjVYgYaG8
.
You need to send this to Jroden. It’s not my question. And as to the link, what she’s saying is true; vegetables have changed over the course of time, as has everything else.
Here is a scientist:
https://www.youtube.com/watch?v=BMOjVYgYaG8
Paleo diet, that’s what it is. I was just curious if the world of nutrition and physiology has changed that much since I studied it in college a long while back.
I’m dating myself, but we used to eat that diet for 3 days as part of the “depletion phase” for carb loading. Talk about feeling lousy.
Setting my friend aside, is there evidence that points to this diet making such a significant metabolic change that a high performance athlete is able to keep from running out of glycogen w/o ingesting carbs during exercise over say 3 hours at a high intensity?
Yes. Look up ketogenic or ketosis.
He is stupid to start this in season though. It takes a couple months of suffering before it works efficiently.
There’s definitely ‘science’ behind it. The question should be “is there any ‘good’ science behind this low carb stuff?”
You need carbs period. Stuff the ‘pseudo’ science and fad diets. Eat carbs (50-55%), fats( 30 - 35%) and protein (15 - 20%) as close to natural source as possible. Nothing complicated. It’s all quite simple really.
You can race on fat and protein rich diets, you just can’t race as fast as you could on carbs. For endurance events that isn’t necessarily a problem, but for races that require intense burst constantly or sustained high output efforts, well you need carbs to do that.
I can run a half marathon in 1:40 with just water, I can run it is 1:23 with water and a little sugar.
Make that a couple of years in my experience.
I have been low carb/ketogenic for a few years now, low carb for 5 keto for 3.
It is only really last year, so 2 years in that I really started noticing the benefits.
For most its more about becoming more metabolically flexible, using a bit more fat and a little less carb to help you go longer and harder. Then on race day you still carb up.
I only ever use carbs in races, but I DO use them, this was my evolution. I started reducing them to the point of low carb in races, but I felt I lost an edge, I have now put the two together to great effect.
When it all clicked into place I did 3 races over 3 weeks with 2nd,3rd, 1st.
Prior to that there were bonks all over the shop!
BUT, it took me a while to make the best out of it.
Diving straight into ketosis is not a good idea, your body just doesn’t have the cellular machinery for it. Gradually reducing carbs when you don’t need them (i.e. not around training) will help to promote these systems so you can start to use them to your advantage.
There is some research that shows increased metochondrial density as well as more lipolytic enzyme activity after adopting to a low carb diet.
There is however no diet showing actual performance improvement, at least not to what I know.
There is some research that shows increased metochondrial density as well as more lipolytic enzyme activity after adopting to a low carb diet.
There is however no diet showing actual performance improvement, at least not to what I know.
what i always learned in school was you can run off fat, but at a really slow pace, like hiking. Actually running at a decent pace, you will need stored glycogen, which gets you maybe 2.5 hous. You need to spare glycogen by eating carbs earlier on.
The proponents of the paleo diet claim , to my understanding, that the body somehow changes and these rules above go out the window and you are able to do that hard 4 hour bike race w/o eating because you are running off fat to make all the glycogen you need.
I have a friend who keeps bonking and racing for crap. He is eating a very low carbohydrate diet that he heard about via Crossfit.
Is there any sort of exercise physiology evidence that eating this sort of diet somehow makes your body metabolize fat doing intense exercise? It sure isn’t doing this guy any favors.
There is some evidence yes:
http://link.springer.com/article/10.1007/BF00392032
In reality, it is hard to pull off for many people, as your friend demonstrates. Most people who apply this approach train on low carbs but race on high carbs. I have some athletes here who eat low carb and running at 10 mph (6min per mile pace), they are still burning primarily fat. They have adapted well. For most, it took 3-6 weeks of adaptation before they started to feel good again. If they are going to race they still generally carb load prior to racing though.
It is not an approach that I generally recommend but if an athlete wants to try it, we try to be sensible about it and we do some testing.
There is some research that shows increased metochondrial density as well as more lipolytic enzyme activity after adopting to a low carb diet.
There is however no diet showing actual performance improvement, at least not to what I know.
what i always learned in school was you can run off fat, but at a really slow pace, like hiking. Actually running at a decent pace, you will need stored glycogen, which gets you maybe 2.5 hous. You need to spare glycogen by eating carbs earlier on.
The proponents of the paleo diet claim , to my understanding, that the body somehow changes and these rules above go out the window and you are able to do that hard 4 hour bike race w/o eating because you are running off fat to make all the glycogen you need.
I think that statement is misleading regarding paleo. Paleo is not low carb. It is no refined grains, processed sugars, etc. You get plenty of carbs from fruit, veggies, yams, etc. as well as glycogen, only it it’s natural form.
The proponents of the paleo diet claim , to my understanding, that the body somehow changes and these rules above go out the window and you are able to do that hard 4 hour bike race w/o eating because you are running off fat to make all the glycogen you need.
I asked you to look up ketosis. It doesn’t appear that you have.
Our bodies have a different process for providing fuel via ketogens rather than glycogen. This must be trained though by severely restricting carbs and even protein for an extended period. Ketogens can fuel the brain and muscles just as well as glycogen. Ketogens are produced from fat, but it is not the same as fat metabolism. Fat metabolism can’t fuel the brain at all, and can only fuel the muscles at a lower intensity.
Care to share your everyday diet and then your race day fueling approach?
There are a few people I know of that do LCHF everyday and then fuel with high carb during races. Seems to work well for them.
50g of carbs while training hard is suicide. You still need carbs post training to recover properly, just enough to refill stores though, not too much to cause insulin spikes.
There’s plenty of science out there if you dig, a guy called Ben Greenfield recently took part in a study and did an interesting N=1 experiment. http://www.bengreenfieldfitness.com/2014/05/how-much-fat-can-you-burn/
Care to share your everyday diet and then your race day fueling approach?
There are a few people I know of that do LCHF everyday and then fuel with high carb during races. Seems to work well for them.
I did not need to look it up, but thanks. I was always under the impression that maintaining the body in that state for any period of time was not healthy. Am I wrong in that assumption? It raises a flag for me when people get ammonia breath.
There’s plenty of science out there if you dig, a guy called Ben Greenfield recently took part in a study and did an interesting N=1 experiment.http://www.bengreenfieldfitness.com/...ch-fat-can-you-burn/
Ben Greenfield?
If you are playing… well you deadpanned that sentence so perfectly, I can’t even tell.
If not… oh dear.
Ben Greenfield… LOL!