Carbohydrate Nutrition Flashcards Preview

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Flashcards in Carbohydrate Nutrition Deck (48)
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1

what are the three macronutrients

carbohydrates
lipids
proteins

2

what is the nature of carbohydrates

composed of carbon, hydrogen, oxygen

3

what is the CHO formula

(H2O)n
glucose = C6H12O6

4

what are the three classifications of cho

monosaccharides
oligosaccharides
polysaccharides

5

what are monosaccharides

basic unit of carbohydrates

glucose
fructose (converted to glucose in liver)
galactose (converted to glucose in liver)

6

what are oligosaccharides

2-10 monosaccharides bonded chemically (disaccharides)

maltose=glucose+glucose
lactose= glucose+galactose
sucrose = glucose+fructose

7

what are polysaccharides

3-thousands of sugar molecule linkages

starch
fiber=cellulose
glycogen

8

what is starch

storage form in plants
amylose-long and straight
amylopectin-branched

9

what are the two different types of fiber

soluble and insoluble

10

what is glycogen

storage form of polysaccharides in mammalian muscle (branched)

11

what are soluble fiber

attracts water and turns to gel during digestion. this slows digestion

12

where is soluble fiber found

oat bran barley nuts seeds beans lentils peas and some fruits and vegetables (help lower risk of heart disease)

13

what is insoluble fiber

it adds bulk to the stool and spears to help food pass more quickly through the stomach and intestines

14

where is insoluble fiber found

wheat bran vegetables and whole grains

15

what is the daily recommended intake of fiber under 50 years of age

over 50 years

38g for men
25g for women


30g for men
21g for women

16

what is the ratio for water insoluble to soluble fiber

3:1 (water soluble =3)

17

where are carbs stored

liver glycogen (100g)
plasma glycogen (3g)
muscle glycogen (400g)

18

where are fats stored

adipose tissue (12,000g)
intrmuscular tricylglycerols (300g)
plasma FFA (0.4g)
plasma triacylglycerols (4g)

19

what is glycogen

storage carbohydrate in muscle and liver

20

how much glycogen does the body store

how much of that does muscle store

how much of that does liver store

2000kcal

400g

90-100g

21

what is glucogenesis

glycogen synthesis

22

what are the steps of glucogenesis

1) start with glucose. ATP is needed to convert glucose into G-6-P

2) G-6P is enzymatically converted into G-1-P

3) G-1-P is enzymatically converted into (UDP)-glucose

4) (UDP)glucose attaches to one end of an existing glycogen polymer chain. UDP is then released

23

what is
glucogenesis
gluconeogenesis
glycogenolysis

glucogenesis = glycogen synthesis from glucose
(glucose to glycogen)

gluconeogenesis (glucose synthesis largely from structural components of noncarbohydrate nutrients
(protein to glucose)

glycogenolysis = glucose formation from glycogen
(glycogen to glucose)

24

what are the four roles of carbohydrates in the body

energy source
(during high intensity exercise)

protein sparer
glycogen depletion triggers glucose synthesis from amino acids

metabolic primer
CHO catabolism serves as a primer substrate for fat oxidation

fuel for the CNS
nerve cells and red blood cells use glucose for fuel

25

excretion of urea in sweat is a measure of

protein breakdown because the bosy is converting proteins into CHO substrates

26

when is most urea seen

in carbohydrate depleted state

27

what are the 5 sources of carbohydrate metabolism

muscle glycogen
glucose
liver glycogen
lactate
CHO ingestion

28

what affects the use of carbohydrate substrates during exercise

exercise intensity
exercise duration
fed state
trained state

29

how does exercise intensity affect the use of carbohydrate substrates during exercise

muscle glycogen in the major substrate used at exercise intensities greater then 50-60% vo2max followed by blood glucose derived from liver glycogen

30

how does exercise duration affect the use of carbohydrate substrates during exercise

as duration increases, glycogen stored deplete and reduced blood glucose. reduced blood glucose and glycogen stores are associated with fatigue