Energy Systems Flashcards
(17 cards)
What are energy systems, where does it come from and what happens during exercise?
Energy systems are used to rebuild ATP.
Comes from the Sun.
Energy systems are in more demand during exercise in order for ATP to be rebuilt.
What are the intensities and durations of the energy systems?
Aerobic -> low to medium intensity, long duration.
ATP-PC and anaerobic glycolytic -> high intensity, short duration.
What happens to ATP during exercise?
Gets broken down into ADP.
Has to get rebuilt by energy sources.
Has only three seconds until it gets broken down.
What are the energy sources used to rebuild ATP?
Carbohydrates -> low to medium intensity = aerobic.
Fats -> aerobic.
Phosphocreatine -> ATP-PC = high intensity.
Protein -> all systems.
What is the ATP-PC system, what is its source and what type of activity is it used by?
The system we use for ten seconds of intense exercise.
Its source is phosphocreatine.
The type of activity that uses it is anaerobic, high intensity exercise.
How does the ATP-PC system work?
ATP - P -= ADP ADP + P = ATP
Breaking down of phosphocreatine to release energy = a coupled reaction.
One reaction releases energy and this energy is used to drive the other reaction, requiring energy.
Creatine kinase is the enzyme used to break down phosphocreatine.
What are the advantages and disadvantages of the ATP-PC system?
Advantages:
- replenished quickly
- no byproducts
- rebuilds ATP quickly
- ATP-PC system can be extended using a creatine supplement
Disadvantages:
- runs out quickly
- have to take breaks to replenish it
- limited supply of phosphocreatine in the body
- 1 molecule of PC broken down = 1 molecule of ATP
- regeneration can only take place in the presence of O2
What is the anaerobic glycolytic system, what does it do, how long does it last and what type of activity uses it?
An energy system that uses energy from the breakdown of carbohydrates to rebuild ADP to ATP.
Lasts up to three minutes.
Used for high intensity exercise.
How does the anaerobic glycolytic system work?
Glycogen -> (glycolysis)
|
2ATP <- Glucose
|
Lactate (lactic acid) <- Pyruvic Acid
What are the advantages and disadvantages of the anaerobic glycolytic/lactate system?
Advantages:
- ATP is regenerated quickly, due to needing few chemical reactions
- when O2 is present, lactate (lactic acid) is converted to glycogen
- useful for producing an extra burst energy
Disadvantages:
- lactate (lactic acid) is a byproduct
What is the aerobic system, what does it do, how long does it last and what type of activity uses it?
Uses O2.
Low to medium intensity.
Three stages:
- glycolysis -> the breakdown of glycogen into glucose.
- Kreb’s cycle -> the oxidation of citric acid
- Electron transport chain -> the transport of electrons using hydrogen carriers.
How does the aerobic system work - Glycolysis
Breakdown of glycogen.
glycogen
|
PFK
|
2 ATP ———->. glucose
|
pyruvic acid
|
acetyl Co-A
How does the aerobic system work - Krebs cycle
The acetyl Co - A forms citric acid by mixing with oxygen.
2 ATP <——— citric acid
| |
H2 CO2
How does the aerobic system work - Electron transport chain
Hydrogen electrons are carried to the electron transport chain by hydrogen carriers.
Occurs in mitochondria (in the cristae).
The electrons are charged with potential energy.
hydrogen
H+ | e-
|. |
water 34 ATP
What are the advantages and disadvantages of the aerobic system?
Advantages:
- more ATP produced than anaerobic systems
- fatiguing by-products
- plenty of glycogen and triglycerides stores
Disadvantages:
- resynthesises ATP slowly
- O2 becomes available slowly
Beta oxidation
Triglycerides
(stored fat in muscle)
|
Glycerol and Fatty Acids
|
Beta Oxidation
|
Acetyl Co-A ———> Kreb’s Cycle
The Energy Continuum
The predominant energy system/provider.
The factors that decide the main energy system are duration and intensity.
Less than 10 seconds -> ATP-PC, e.g. shotput.
8-90 seconds -> anaerobic glycolytic, e.g. sprints in football.
90 seconds - 3 minutes -> anaerobic glycolytic, e.g. 800m.
3 minutes + -> aerobic, e.g. marathon.
