ch 4 - carbs Flashcards
Carbohydrates are found in the body predominantly in the form of ________ (mostly in the blood) and in the storage form of ________ (predominantly in muscle and liver tissue).
glucose; glycogen
when added to food glucose is referred to as
dextrose
galactose is found in food only as
part of lactose
3 monoscacharides
glucose, galactose, fructose
sucrose
glucose + fructose
lactose
glucose + galactose
maltose
glucose + glucose
sucrose found in
fruits, veggies, honey, maple syrup
most adults lose their ability to digest
lactose
which disaccharide is minor in most diets
maltose
polysaccharides
starch, fiber, glycogen
starches in food may be…
straight chains (amylose) or branched chains (amylopectin)
carbs: The majority of digestion takes place in the ______. The majority of absorption takes place in the _______.
small intestine; small intestine
glucose metabolism: the regulation of
blood glucose concentration
glucose metabolism: the immediate use of
glucose for energy
glucose metabolism: the storage of
glucose as glycogen
glucose metabolism: the use of excess glucose for
fatty acid synthesis
glucose metabolism: the production of glucose from
lactate, amino acids, or glycerol
beta cells release
insulin
alpha cells release
glucagon
high GI food effects
blood glucose rises more quickly, reaches a higher level, and declines more quickly
high GI food insulin response
higher and remains higher, even though the same amount of carb is consumed
T or F glucose is preferred over glycogen
false
T or F: Muscle glycogen utilization is no different when athletes consume a carbohydrate drink, compared to a placebo drink during high-intensity activity.
true
T or F: Exercise has a strong insulin-like effect, meaning exercise stimulates glucose uptake from the blood.
true
T or F: Glycogenolysis is the release of glucose from glycogen, caused by glucagon.
true
The stress of higher exercise intensity results in a substantial stimulation of the sympathetic nervous system; this leads to a release of two important stress hormones:
epinephrine and norepinephrine
the catecholamines stimulate
glycogen breakdown and gluconeogenesis and thus provide an additional mechanism to regulate blood glucose.
cortisol aids blood glucose regulation indirectly by
by stimulating the breakdown of proteins into amino acids that may be used in gluconeogenesis.
low intensity or short duration skill based activities carbohydrate recommendation
3-5 g/kg/d
low intensity long duration carbohydrate recommendation
5-7 g/kg/d
very high intensity very short duration carbohydrate recommendation
5-7 g/kg/d
high intensity short duration carbohydrate recommendation
5-7 g/kg/d
moderate intensity moderate duration carbohydrate recommendation
6-8 g/kg/d
intermittent high intensity moderate to long duration carbohydrate recommendation
6-8 g/kg/d and 8-10 g/kg/d during heavy training and competition
moderate to high intensity long duration carbohydrate recommendation
6-10 g/kg/d
moderate intensity ultralong duration carbohydrate recommendation
8-12 g/kg/d
recommended carb intake to enhance performance in
- high intensity ~90 min
- mod-vig intensity > 2 hr
- high intensity > 2 hr
30-60 g/hr
recommended carb intake to enhance performance in ultraendurance comps
up to 90 g/h
Athletes who perform endurance exercise or intermittent high-intensity exercise for more than 1 to 2 hours are at risk for
glycogen depletion, low blood glucose, and fatigue during training and competition.
foods containing oligosaccharides
onions, beets, cabbage, garlic, apples, watermelon, wheat, rye, beans, legumes
foods containing sucrose
sugar sweetened foods
foods containing fructose
fruits, honey, added fructose
The recommended range of daily carbohydrate for athletes in training is
3-12 g/kg/d
The two factors needed to optimize muscle glycogen resynthesis after exercise are:
carbohydrate and insulin
