Lecture 5 - Fuel Flashcards
What fuel do we use in our body based on?
Different types of fuel for different intensities
What is the most important fuel for moderate intensity?
- Most training and ocmpetitons are at least moderate intensity, so 70%VO2max and carb is a more important fuel to support muscle glycogen for peak performance
- 5-7g or carb/kgBW per day for athletes
How much protein should you take in for athletes?
Protein can be 1.2-2g/kgBW per day
What source of energy is used for peak performance?
Carbs
What are the main sources of carb?
Blood glucose
○ Supplied by liver glycogen, external sources (food), GNG
Muscle glycogen
○Need to max ability to use this so that the next time you can benefit from this
When should fluids, c arbs, protein and fat be consumed before you partake in activity?
- Fluid all the way up unitl activity
- Carb up until time of activity, as you get closer to exercise the volume of food should go down
- Protein and fat delay gastric emptying and digestion so we don’t really want this in your stomach so we recommend hours before activity
What happens to blood flow during activity?
○ Blood flow diverted during activity so wont digest food
What kind of carbs should we have right before activity and hours before activity?
○ Complex carbs further out, simple carbs closer to exercise, but don’t want fibre to sit in stomach and casue discomfort
Who should you have fuel for activity?
• Activities lasting >60 mins
○ Activities lasting >2-3hour
○ Activities lasting 45-60min but only at high intensity (75% VO2 Max)
○ Note also that these recommendations are to enhance performance not simply to complete the activity
How many g of carb should you have /hr during activity?
30 to 60g/hr
Why should you have fuel during activity?
○ Spares both lover and muscle glycogen, extending their use
○ Readily absorbed and can be used by muscles and the brain as a third carb sources
○ May augment the need for GNG which spares protein
For endurance events greater than 30 mins how much carbs should you have before exercise?
5-12g/kg/d
-Going to be training and burning thorugh a lot of. Glycogen, this is why its so high
For strength sports how much carb and protein do you need?
Before:
Carb: 4-7g/kgBW
Protein: 1.6-1.7g/kg
During:
Carb: 0.5g/kg
Protein: None
Recovery:
Carb: 1.0-1.2g/kg/hr
Protein: 20g or 0.3g/kg
-also 2-2.5g of leucine
If you are a serious athlete what should be considered thought the year?
Specific training protocols throughout the year
- Don’t want to send athlete into comp exhausted
- Total cals drop to almost half in the off season
What are the general recommendations for fuel post activity for serious athletes?
<8hr between practice/comp
1-1.2g/kg carb
0.25g/kg or 20-25g of protein
What is the most beneficial way to replenish glycogen?
Combo of protein and carb is the most beneficial. Carb and protein were better for % recovery of glycogen
-Mix of carb and protein had a better glycogen recovery over 4 hr period
How much carb and protein do we really need for recovery?
Plateau 1-1.2g carbs because the body can only go so far and glycogen can only replenish so fast
○ No benefit of more carbs
What is the ratio needed for carbs/protein in recovery?
• Got a lot more glycogen right after activity, waiting is no good for carbs
• 70g of mix-25g protein= 50g should be carbs
○ Protein is a fixed number so carbs is whatever is left over
-70g of the mix Is based on BW (1-1.2g/kgBW)
30 mins after exercise what re the muscles sensitive to?
Sensitive to glucose, doesn’t matter if glucose is present or not
-Take advantage of this window we can replenish a lot of glycogen
How often is protein being turned over in our bodies?
Protein turnover is constantly occurring in our bodies
- Balance between breakdown and synthesis
- You need more to replenish the turnover
How long does RE enhance protein synthesis after exercise?
Approximately 24-48hr post exercise
-If you have damage happening from training and adaptation, there is a turnover of protein
How much does RE increase muscle protein synthesis by?
40% (myofibrillar)
• Overall synthesis increases by 56%
• Dependent on volume and into site of activity
• Includes bone growth, connective tissue, muscle enzyme
When do we reach peak protein synthesis at?
Peak synthesis reached at 23hr post exercise, then declines somewhat and recovers
• Continues into the next day
What can help to increase muscle protein synthesis?
Not surprisingly, feeding along can also increase muscle protein synthesis above resting values (about 130% above resting values).
• Body has new AA s to turn over things
What does a combination of exercise, protein and AA supplementation lead to?
Exercise + protein/AA supplementation
• Incfreease in muscle prptein synthesis by 50% abose exercise alon
When should you administer protein/AA supplements after exercise?
Timing of administration is unclean and does not seem to play a major role
• Close to exercise may help a bolus
What is the dose of EAA?
• 20-30g of EAA
-Bolus seems better
What is the source of protein that you should be getting?
• Unclear, as long as it has the total compliment of proteins then you’re good
Leucine
Which protein is slightly better and gives more leucine?
Whey protein is better and gives you the most leucine (2-2.5g) in small quantity for optimal protein synthesis
Should protein be supplemented?
- Can be done but need to be creative about it
- Plant based sources of protein are less digestible than meat
- Veg: add 10g protein to account for losses in digestabilibty
- Vegan: add 20g
Volume of food will increase from omnivor to veg/vegan
Whats carb loading?
Goal: super compensate glycogen levels
○ Depletion of glycogen via low carb diet and activity
○ Replenish with high carb diet
what can a high fat diet for 4-7 days lead to?
○ Increase fat oxidation
-Tries to burn more off in response to high energy
○ Spare muscle glycogen
○ Increase fat transport
○ Increase in hormones sensitive lipase
- The rate limiting enzyme fo fat hydrolysis
○ Decrease in pyruvate dehydrogenase
- A rate limiting enzyme of glycogen breakdown
What can a high fat diets do and what kind of exercise does it affect?
But only for sub-maximal exercise
may delay exhaustion during protlonged exercise
Is there a difference between high protein and low carb diets and high intensity exercise?
No difference in strength performance between
What does glycogen depletion and low carb diet lead to?
Glycogen depletion and low carb diets (<10%) for 3-4 days reduces exercie capacity
○ You ability to work at high intensity is decreased is decreased
What does training on a low carb diet look like?
Leads to enhancements in
○ Carb and fat metabolic proteins
○ Mitochondrial biogenesis (more you have the more energy you burn and faster you go)
• This occurs despite a reduced workload
○ 7-8% lower exercise intensity
○ Never do this on competition day
Low muscle glycogen levels
