It's far from
impossible—many factors come into play.
- Personal metabolism
- Types of carbohydrates being ingested
- Timing of carbohydrate consumption
- Amounts of fiber/fat eaten with carbs
- Exercise types, amounts, and durations
- Fluid intake
One case in point is
Dave Scott (vegetarian & 6-time Ironman champion).
I'll post his typical day's diet:
b r e a k f a s t
A couple packages of Shredded Wheat cereal, with 3 tbsp of plain non-fat yogurt, drowning in non-fat milk.
A couple of bananas.
A couple of pieces of dry whole wheat toast.
Half a dozen rice cakes.
Two or three apples.
(I like a hearty breakfast, he says. Sounds like it'll sure get your blood sugar flyin' high)
l u n c h
Cottage cheese & tofu on a corn tortilla, with tomatoes and salsa.
A couple of apples
A piece of whole wheat bread
d i n n e r
either
Soup, of
steamed vegetables
Baked potato with cottage cheese or yogurt.
or
Tortillas stuffed with beans, onions, tomatoes, cottage cheese, tofu and hot spices.
Beans and rice.
and
I almost always eat three or four more apples.
I round it out with a green salad, and maybe a fruit salad.
Depending on exact portions, that can be as much as 80% carbohydrates.