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Old 01-05-2012, 09:27 PM   #17 (permalink)
RunbikeSki
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Quote:
Originally Posted by VitoVino View Post
You enjoy running. I'm curious as to what % of carbs you can operate efficiently on while maintaining your running.
I can actually function quite well on 20% carbs as long as I have enough total calories. It takes me a couple of weeks for my body to adapt, but once it did 10 milers on 20% carbs @ 1200 calories was doable. I've never been able to go lower that 20%.

As I've been told, most average atheletes only store about 30 minutes of glycogen in muscles and a bit more in the liver (HC you can probably chime in on this). After 30 minutes of continued aerobic work, the body starts switching over to the fat reserves, but the conversion of tri-glycerides to glucose is not as efficient as burning the glycogen stores, thus you eventually tire. In any event, if you don't eat much after your run, your body will continue to work off the fat reserves to restore glycogen. Training does many things, among them is improving that efficiency at extracing glucose from fat. No doubt, some people are physiologically better at adapting to low carb diets than others. That's the basis behind "eating according to blood type". An interesting concept, but LOTS more research needs to be done.

Quote:
Originally Posted by volleyballgranny View Post
I spent about 20 years participating in competitive volleyball, basketball, and softball on 11-15% carbs (all from vegetables and dairy products). It worked for me. My body was leaner, less fat, than many of my competitors, though I was not thin. My endurance we better than those who tanked up on carbs and then crashed. The protein gave me a longer 'burn.' FYI:
I do low carb because it helped stave off diabetes (originally diagnosed with hypoglycemia) for 32 years. Now, when I measure blood glucose (fasting and after meals), I can see an immediate impact whenever I add carbs back in my diet. My body cannot handle wheat or corn--it used to make me fat, now it makes me sick. After the last hospital stay (of 5) last Spring, I don't even try small portions of wheat and corn any more.

One of the things that researchers are beginning to say is that our concept of weight loss--eat fewer calories than you use to lose weight--is not valid (by itself) because there are other things that impact weight loss, such as heredity and vitamin deficiency. Also, the researchers say that if 'eat fewer calories than you use' worked, fewer people would be overweight and all diets would work for any person. They don't.
I too find that a higher protein diet gives me a longer 'burn' once I have adapted. At that point carb loading for a race just doesn't work for me - infact it backfires and I get sluggish. One of my long time running buddies who switched from a high carb/vegan diet to a low carb vegetarian diet with lots of veggie protein sources has noted the same thing. She says she has a lot more stamina and endurance.

Volleyball, it would appear that you have a gluten intolerance, which is a complicating factor in the carb vs no carb debate. I would agree that some diets work better for one person than it does for another. Part of that is that "the best diet is the one you can stick to". If you are not much of a carnivore doing paleo just won't work for you. But I also think that there is a hereditary component to food tolerences and metabolism. And as a number of us post menapausal-types can tell you metabolic rates definitely change with time and age.

Quote:
Originally Posted by volleyballgranny View Post
And, at a certain point, they stop losing and stay the same--even though their calorie intake continues to be much less than they use. Some of the recent studies were done using that type of information.
Quote:
Originally Posted by volleyballgranny View Post
PS: One of the things I read was a 30 page compilation of about 150 studies done over the last 30 years. It included studies on starvation (such as refugee camps), anorexia, and other eating disorders--where, at some point, the weight loss stopped, but the shutdown of vital organs continued. It was very interesting...
This definitely happens, but the science that explains it this is far from complete. At some point most bodies revert to consuming fat and muscle in an attempt to maintain, primarily, the brain. There were not may svelt people rescued from Dachau.

The whole starvation below 1200 calories is a protective guideline that the AMA has adopted - according to my diet doc. As with all medical guidelines its goal is to be as protective of the "average" person as possible. Unfortunetly the "average" person doesn't really exist, so for me his recommendation was closer to 1000 cals which worked just fine - as long as I could maintain it . 1000 cal ain't much food.
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