week 3 Flashcards
name complex carbs
- amylopectin starch
- amylose starch
list fast carbohydrate and slow carbohydrate
fast
- glucose
- maltose
- sucrose
- maltodextrins
- starches rich in amylopectin
slow
- fructose alone
- galactose
- isomaltulose
- starches rich in amylose
what determines a fast/slow carbohydrate
- its about how readily the carbohydares are available for the body to use
- how fast it eneters the blood, and the rate that its utilized by the muscles
- why is amylopetctin a fast carbohydrate
- why is amylose a slow carbohydrate
- its a fast carbohydrate because the branches can be easily broken down quickly at different sites by enzymes.
- the long string structure makes it harder and longer to breakdown
which simple sugar is slow in breakdown?
fructose when ingested alone
new guidelines of carb feeding during exercise
0-1hr requires how much carbs
- les than 30g/h of carbs
- this shows a little benefit to performance
new guidelines of carb feeding during exercise
1-2 hrs how much carbs do you ingest and what type
- 30g/h
- single or multiple transportable carbs
new guidelines of carb feeding during exercise
2-3 hours of exercise how much carb do you ingest and what type?
- 60g/h
- singele or multiple transportable carbohydrates
new guidelines of carb feeding during exercise
3 hours and more of exercise requires how much carbs and what type
- 90 g/h of carb
- only multiple transportable carbohydrates
- what is multiple transportable carb? (MTC)
- what is the role of mutltiple transportable carbohydrate?
- why is multiple transportable carbohydrates beneficial in long exercise duration?
- when using multiple transportable carbohydrate, whats the maximal exogenous oxidation?
- what are other benefits of multiple transportable carbohydrates?
- multiple transportable carbohydrates is consuming two or more different types of carbohydrates such as (glucose + fructose)
- refers to sugarsthat are transported across the intestine bystimulating more than one protein transporter (e.g.,glucose [via SGLT1] and fructose [via GLUT5])
- In extreme endurance scenarios lasting three hours or more, there’s evidence that higher carbohydrate ingestion rates, up to 90 grams per hour, can be beneficial. To achieve higher carbohydrate ingestion rates, there’s a move towards using MTC combinations like glucose and fructose/ maltodextrin and fructose. This is particularly relevant when trying to surpass the body’s oxidation limit of around 1.1 grams per minute.
- 1.75 g/min
- increase exogenous carbohydrate oxidationby 20-50% above single transported carbohydrates. 2. improves gut comfort. 3. inhance performance in >2.5-3 h of exercise
why is having too much carbohydrate not beneficial?
- the body is only cample of oxiding carbs around 1.1 grams per minute.
- having more carbs than what can be oxidized during exercise may cause discomfort in the body
- carbs will stay in the stomach which can cause bloating and nausea
- this may affect performance outcome
what are the benefits of carb feeding?
- in endurance events, carbohydrate intake maintains plasma glucose concentration. (study showed participants with carb intake could exercise for an hour longer than placebo before exhaustion)
- associated with higher whole-body total carbohydrate oxidation rates during exercise (important for muscle contraction)
- decline of carbs leads to fatigue and the bodies relies more on fat oxidation. but during higher intensities fat metabolism is slow. suppling ATP to working muscles is not efficient so the person fatigues
- spares liver glycogen stores that may be needed later on in endurance based sports to sustain blood glucose levels.
when igesting high amounts of glucoe, why is glucose oxidation less than what is being ingested?
- limited glucose transporters
- maximal exogenus rate is 1g/min
