[quote]E-man wrote:
Cthulhu wrote:
Fat will only be stored if there is fat present. Malonyl -CoA exists in high amounts when there is plenty of metabolic fuel present. Thus, carnitine acyltransferase is inhibited and
this in turn prevents acyl-CoA from crossing into the cell?s mitochondria. Another enzyme is inhibited by the presence of NADH and Thiolase is also inhibited by the presence of Acetyl-COA. In short, when a lot of glucose is present, fatty acid metabolism is inhibited.
It is the last sentence that clues us in here. Basically, a cell will not convert fats into energy if there is glucose present. When the cell has carbs and sugar to work on, it will not convert the fat to energy, thus the fat gets stored.
This is why the low carb diets work, with little to zero carbohydrates and
subsequently glucose to work on, the fat will be used for energy. This is exactly why the high carb diet works too. When no or little fat is present, it won’t be stored as fat.
In addition to this, it is important to realize that it costs the body quite a bit of energy to take carbs and store them as fat. This alone is actually a positive. There really needs to be some form of fat present to make it easier.
You seem to be very knowledgeable about human metabolism so I have a question. If you’re low-carb dieting and carbs are extremely low and your body is well into ketosis then if you were to run say sprints or engage in another anaerobic activity would gluconeogenesis occur on amino acids and possibly muscle tissue? I know at the upper end of anaerobic intensity carbohydrates and glycogen is almost 100% of your body energy source and fatty acid oxidation can keep up at those intensites. So therefore would you use protein and perhaps muscle tissue broken in amino acids as energy? If so then it only makes sense to engage in long duration aerobics on restricted carbs and any high intensity cardio would be detremental.[/quote]
Yes.
Gluconeogenesis probably will occur.
It’s pretty simple,actually.
If you’re low carb dieting(ketosis) and you’re doing high intensity cardio,then you risk losing muscle tissue.
However,if you do a somewhat low intensity jog you’ll be burning mostly fat.
I’ve done this before when I was cutting.
I had to get in shape fast for a special occasion and decided to try a very low carb diet.
I did the low intensity jog for about 30-45 minutes every morning or night.
So,if I were you I’d do some lower
intesnity jogging.
Cthulhu