Week 6 - carbs and exercise

monosaccharides are absorbed through the wall of the __ intestine into capillaries leading to the __ vein.

small; portal

Glucose and galactose are absorbed by ___ active transport coupled to __+ transport into the epithelial cells and then move into the blood by facilitated diffusion.

second; Na

___ is absorbed through epithelial cells and into the blood by facilitated diffusion
- NOT active transport
- requires carrier protein (GLUT5-> GLUT2/5)

fructose

__ doesn't require a lot of energy (lower thermic effect) because it doesn't require ATP for transport

fructose

fats and water use ___ absorption (no energy)
fructose uses ___ absorption (transporter protein)
amino acids and glucose use ___ absorption (transporter and ATP)

passive; facilitated; active

___ state means fasting

postabsorptive

____ state:
After an overnight fast, blood glucose is maintained by glycogenolysis and gluconeogenesis in the liver
� ___ provides 65-75% of the glucose released.
� ____ provides the remaining 25-35% of the glucose released by the liver.
� Muscle glycogen

post absorptive; glycogenolysis; gluconeogenesis; cannot

____ state is fed state:
� Absorbed glucose is being stored as glycogen (____) in skeletal muscle and ___.
� Most cells of the body are removing glucose for energy (___), especially neurons and red blood cells.
� Adipose cells remove glucose to form ___ n

postprandial; glycogenesis; liver; glycolysis; glycerol

Most galactose and fructose are converted to ___ in the ___.
�____ is preferentially stored as liver glycogen.
� Rate of liver glycogen synthesis is ____ as great for fructose compared to glucose.
-- Once liver glycogen has been restored, fructose serves

glucose; liver; fructose; twice; triglyceride

insulin ____ glycogenolysis, gluconeogenesis, and ketogenesis

decreases

glucagon, epinephrine, and norepinephrine ____ glycogenolysis, gluconeogenesis, and ketogenesis

increase

an increase in blood glucose levels stimulates ___ cells of pancreatic islets to release insulin, increasing blood levels of insulin which targets ___ cells to enhance:
1. ___ transport of amino acids into tissue for protein synthesis and
2. ___ diffusion

beta; tissue; active; facilitated

decrease in plasma glucose concentration (exercise, fasting) stimulates ___ cells of pancreatic islets to release ___ which:
1. stimulates glycogenolysis and gluconeogenesis in the ___ to increase levels of glucose (and insulin) in plasma
2. stimulates fa

alpha; glucagon; liver; adipose; HSL

the pancreas has __ and ___ functions

exocrine; endocrine

___ functions of the pancreas:
secrete ___ enzymes into the small intestines; break down macronutrients

exocrine; digestive

___ functions of the pancreas:
release insulin and glucagon

endocrine

at ___ VO2max, cortisol, GH, and glucagon increase greatly, while insulin decreases slightly
using carbs more, so the things that help you get carbs into the blood go up
why does insulin go down if glucose is going into the blood?___ mobilization from mus

high (high intensity); GLUT4

muscle ___ mobilizes GLUT4

contraction

should a diabetic eat, take insulin, and then workout at night without eating again afterwards?

no (they might go hypoglycemic)

training ___ insulin and glucagon responses
this is because you sensitize all the receptors for hormones

blunts

Sympathetic response to exercise:
Blood glucose __ stimulate receptors in the hypothalamus.
Sympathetic nervous system is __.
� Adrenal medulla releases ___ which stimulates glycogenolysis in the liver and release of glucose into the ___.
� Sympathetic ne

decrease; activated; epinephrine; blood; adipose

as intensity increases, catecholamine release __ nonlinearly
this causes lipolysis and glycogenolysis to ___
the rate to which this occurs depends on exercise ___

increases; increase; intensity

__ intensity = more rapid depletion of stored glycogen

higher

catecholamines INCREASE glycogenolysis in the liver and lipolysis in the adipose tissue
but catecholamines DECREASE ___ entry into the tissue

glucose

factors that influence carb use during exercise:
_____ (king)
____
initial ___ levels
___ status

intensity; duration; glycogen; training

the harder you go, the more rapidly you deplete __ stores
depletion was greater at higher VO2 levels

glycogen

there was a decrease in muscle glycogen with a moderate CHO diet
BUT was there a difference in performance for the Time Trials on day 7?

no

a trained individual is more efficient at using __ energy sources

both

with exercise at 80% VO2max:
Subjects were able to ride significantly longer after drinking __ than __.

milk; glucose

rebound ___ happens in high intensity exercise when glucose was given 30-60 minutes before exercise
increased CHO catabolism and reduced fat mobilization
but also, glucose ingestion has been shown to conserve liver glycogen
studies at moderate intensity s

hypoglycemia

�Carbohydrate feeding __ to __ hours before exercise has been found to improve performance.
oPre-comp Meal
�___-____g CHO (3 - 5 g/kg)
� Solid or liquid
� Relatively little fat or fiber (avoid fried foods)
� Limit ___

3; 4; 150; 300; protein

__, __, and __ should be limited before working out because they take longer to digest

fat; fiber; protein

Recently, Murakami et al. (2012) offered 3 days of high CHO, then a high __ meal 3 hours before exercise.
- No difference was found from a high CHO meal 3 hours before exercise.
exercise intensity wasnt really high; both groups had high CHO in the days be

fat

bread, glucose, pastry, rice, cereals, potatoes, and honey are ___ GI

high

spaghetti, oatmeal, sweet potatoes, grapes, oranges, and potato chips are ___ GI

moderate

Apples
Cherries
Peaches
Plums
Beans
Lentils
Fructose
are __ GI

low

Thomas et al. fed glucose (hi-GI Control), potato (hi-GI), lentils (low-GI) and water 60 min prior to exercise.
� Exercise intensity was 65-70% VO2max
� Blood glucose prior to exercise was ___ with the potato and glucose than lentils as was the insulin re

higher; lower

feeding during exercise spares muscle ___ and is helpful in maintaining blood glucose for exercise longer than __ minutes

glycogen; 60

endurance time was longer in carb solutions but these runners experienced more __ distress (higher carbs, higher distress)

GI

CHO doesn't seem to be beneficial:
� When subjects are __
�During high intensity exercise when fatigue is due to accumulation of __+ in muscles (lasting 20-30 min)
�During events lasting __-__ min

hyperthermic; H; 30; 45

Does CHO feeding improve short-term intermittent high intensity exercise?
� After 60 min of aerobic exercise, __ output during 5-15 min of high intensity exercise improves.
� Shuttle-running tests with repeated 15 min bouts that simulate many "stop and go

power;

All macronutrients (CHO, Fat, PRO) when consumed are absorbed and oxidized although at varying rates
� If underfed, the rate of oxidation will ___
� If overfed, the rate of oxidation will __

decrease; increase

higher oxidation rates can be achieved with multiple transportable carbs especially at high intakes (1.75g/min) is the new ceiling for oxidation;
if you combine ____ and fructose you might have the best ability to transport carbs across intestinal lumen a

glucose

were CHO mouth rinses more effective in a fed or fasted state?

fasted

modified starches:
virago is ___ GI very ___; used for prolonged exercise
UCAN is a __ GI and is very ___

high; fast; low; slow

Effect on muscle glycogen resynthesis
� __ of carbohydrate ingestion
� __ of carbohydrate fed
� ___ of carbohydrate fed
� Presence of other nutrients with CHO
� Effect of ___ type
� Effect on subsequent performance

timing; type; amount; exercise

you can still recover and restore glycogen stores if you eat later, but if you're competing again the same day then research shows that you should eat within __ hours post exercise
delaying eating only matters short term for muscle glycogen storage

2

for a power perspective, low carb __ performance / force production

impairs

__ __ is the enzyme that stimulates muscle glycogen synthesis.

Glycogen synthase

GS __-form is the LESS active form of the enzyme which is activated by glucose-6-PO4

D

GS __-form is the MORE active form which is activated by exercise, ___, and glycogen depletion.
activated at the end of exercise
"primed

I; insulin

Why would carbohydrate feeding immediately after exercise enhance glycogen synthesis?
Glycogen ___ - increases the percentage of activated __-form of glycogen synthase
Presence of ___ - enhances glycogen synthesis
___ - GLUT-4 is present at cell membrane

depletion; I; insulin; exercise

glycogen ___ is holding more glycogen than a physically unfit person could

supercompensation

post-exercise would be ___ GI
for restoring glycogen (periexercise nutrition)

high

after exercise:
__ GI carbohydrate-rich foods
Either a single large meal or small frequent meals will replenish glycogen stores.
Should be consumed as __ as possible after the activity*
Avoid ___ and slow-digesting carbs

high; soon; fructose

Tarnopolsky et al:
There was NO SIGNIFICANT DIFFERENCE in muscle glycogen synthesis between protein + CHO and CHO, but both were better than the ___.

placebo

Eccentric exercise causing muscle soreness and damage is accompanied by reduced muscle glycogen ___.
May be due to damage to the sarcolemma and interference with __ transport into the muscle fiber.
May also be due to the inflammatory response and increase

resynthesis; glucose;
oxidation

How much carbohydrate is required to replace muscle glycogen stores during daily training?
Simonsen et al. (1991) examined the effects of 5 g CHO/kg bw/d vs. 10 g CHO/kg bw/d in male and female rowers for 4 weeks.
Power output increased 10.6% in ___ CHO g

high; low

Feed approximately __-___g of carbohydrate per kg body weight each hour for the first __ hours after exercise for fast recovery.
Within the first 6 hours after exercise, ___ GI foods or simple CHO (glucose, sucrose, maltodextrin) provide the best glycogen

1.0; 1.5; 4; high;

Provide a CHO replacement beverage containing __-__ g CHO immediately after exercise if athletes are eating self-selected diets, are unable to eat within 2 hrs, or do not feel hungry after strenuous exercise.

70; 90

recap:
Pre-competition Feeding: __-__g/kg BW
- Particularly important for > __ min activity
- Important consideration must be given to athlete's preference, GI comfort and event type
During
<__min - not necessary
__-75 min - small amount (mouth rinse)
- S

1; 5; 60; 45; 45; carb; 2; 1

accelerade and goo octade were his race __ sources

fuel

Over a 24-hr period, feed __-__g carbohydrate per kg body weight for moderate-duration, low-intensity training.
For moderate or heavy endurance training or competition, your recovery diet should include __-__ g carbohydrate/kg per day.
Extreme exercise tr

5 7; 7 12; 10 12

do people exercise hard enough to make the classical carb loading useful for them?

no

why would you workout 6 days prior to competition to deplete glycogen stores?

to increase enzymes

classic carb loading method:
Requires exhaustive exercise run
- Reduce glycogen about __ days before event
Low carbohydrate diet for ~3 days
__-___g CHO per day to further deplete
This should increase glycogen ___ in SKM
3 days before event, switch to hig

6; 60; 100; synthase; 400

depletion taper technique:
day 1 ____
day 2-4 ___ diet (50% CHO) tapering exercise 90-->40min/day
day 5-6 ___ CHO (70%) tapering exercise 20min/day
day 7 ___ CHO, rest
day 8 = competition
__-___g/kgBW CHO

depletion; mixed; high; high; 10; 12

classic and moderate super compensate __ to the same amount

glycogen