Carbs Flashcards
What 2 places is glycogen stored in the body?
Liver and Skeletal Muscle
How much glycogen in liver?
100-200 g
How much glycogen in the skeletal muscle?
350-750g
Plasma glucose is the primary source of fuel in what state?
Rest
Muscle glycogen is the primary source of energy at what state?
Exercise–> Increasing with intensity
Why may a high carb diet increases time to fatigue compared to low carb diet
Start with a higher muscle glycogen level
What supports blood glucose homeostasis overnight?
Liver (up to 50% is lost)
Higher Liver glycogen results in higher
Time to Fatigue
What is wrong with the existing guidelines for pre-exercise carb intake?
To broad 1-4g/kg
How much glycogen is lost from liver overnight?
50% (50-100g)
CHO feeding during exercise is seen best in what fibres?
Type 1 Fibres (slow twitch) (aerobic more mito)
compared to Type 2 (Fast Twitch)
Carbohydrate feeding during exercise improves time to fatigue how?
Spares muscle glycogen
True or False During exercise that is 75 min/ (~20-30km on bike carb is needed?
False
How much carb is needed for exercise that lasts no longer than 2.5 hours (~50 km)?
30-60g per hour
During exercise that last 3 hours (greater than 75 km) carb should be consumed up to how much per hour?
90g per hour
What is the dose-response relationship between CHO intake and performance
Increase CHO = Increased Performance to approx 68-88 g/h
more = GI Discomfort
How much CHO g.hour is optimal
68-88 g/h
Glucose transporters
SGLT1;GLUT2
Fructose Transporters
GLUT 5 and GLUT 2
Sucrose Transporters
SGLT1;GLUT2;GLUT 5
Sucrose is better because
2 monomers, glucose + Fructose
Sucrose versus glucose for gI discomfort
Sucrose
True or False Glycogen in skeletal muscle and liver stores are limited?
True
What do you need to be careful with when using gels?
Make dehydrated, need to consume some water
At the beginning of exercise, are endogenous or exogenous stores used?
Endogenous stores
At the end of long exercises, 2+ hours of endogenous or exogenous stores are used?
Exogenous Stores
CHO rate and form 1 hour
30g of glucose
CHO rate and form for 2 hours
90 g (30+60g)
Glucose
CHO amount and form for every additional hour 3 and up?
110 per hour (200g at 3 hours)
Sucrose
Reccomendation for carbs post-exercise
DONT DELAY
1-1.2 g/kg/h for first 4 h then resume daily
NO mention of carb source/type of the liver
Why is carb intake post exercise important?
Muscle Glycogen Resynthesis
Best protein source for recovery
milk (0.24 g/kg or 0.4g/kg)
A combo of what enhances glycogen resynthesis
CHO (0.8) + Protein (0.4)
How much caffeine should be coingested with carb to enhance muscle protien resynthesis POST exercise
8 m/kg
POST EXERCISE
Watch out cuz of sleep
How much carb is needed for muscle glycogen resynthesis per hour for how many hours post exercise
1.0-1.2 g/kg/hr for 4 hours post
How much protien post exercise
0.24 g/kg
How much carb pre-fuelling
2g/kg CHO
0.5 g/kg/h for 4 hours
Why does carb rinsing work?
Tricks the central system (brain) not to shut down when we are lacking glycogen
Not actually consuming/don’t want to shut down and keep using stores
Many different bodies, usually improve in speed/distance acheived
