Energy Systems Flashcards
What are the three main energy systems?
ATP- PC system
Lactate system (anaerobic glycolysis)
Aerobic system
What is the ATP- PC system?
Anaerobic system
When exercise is short and high intensity
Generates 1 ATP
Only lasts 8-10s as CP stores run out
To reform ATP, CP is split and the Pi is donated to ADP to reform ATP
CP stores can replenish with enough rest, for every second of workout, 10 seconds rest is needed
What is the Lactate system (anaerobic glycolysis)?
Anaerobic system
Used when exercise is high intensity and for longer period
Lasts up to 3 mins
Generates 2 ATP’s
Occurs in sarcoplasm
Glycogen—> glucose—> pyruvic acid—> lactic acid
What is the aerobic system?
With oxygen
Used when exercise lasts over 3 mins
Three phases; • glycolysis
• krebs cycle
• electron transport chain (ETC)
Glycogen—> glucose—> pyruvic acid—> Krebs cycle—> ETC
Produces 38 ATP’s
What are the stages of the Krebs cycle?
- Oxygen is oxidised into 2 acetyl groups
- Acetyl groups combine with oxaloacetic acid, forming citric acid
- Hydrogen and carbon are given off
What are the stages of the ETC?
- Hydrogen carriers carry the hydrogen to the ETC
- Hydrogen splits into H+ ions
- Hydrogen ions are oxidised into water
- Electrons provide the energy to reform ATP
Advantages to ATP- PC system
ATP can be re synthesised quickly
Phosphocreatine stores can be re synthesised quickly
No fatiguing by products
Can extend use of system by taking creatine supplements
Disadvantages to ATP- PC system
Only limited number of natural body phosphocreatine stores
PC re synthesis can only take place in the presence of oxygen
Advantages of the lactate system
ATP can be re synthesised fairly quickly
Lasts longer than the ATP- PC system
Can be used for a sprint finish
Disadvantages of the lactate system
Lactic acid is a by product- will fatigue athlete
Only a small amount of energy can be released from glycogen under anaerobic conditions
Advantages of the aerobic system
More ATP is produced
No fatiguing by products
Lots of glycogen and triglyceride (fat) stores, so exercise can last for a long time
Disadvantages of the aerobic system
Complicated system so cannot be used straight away (slow energy)
Fatty acids require more oxygen to break down than glycogen stores (15% more)
