Aerobic energy system

Aerobic energy system

1. Krebs cycle

   • oxidation of citric acid
     • removal of hydrogen atoms from the compound which enter the final stage of the aerobic system - electron transport system
   • production of carbon dioxide
     • removal of hydrogen means only carbon and oxygen remain
     • these combine to form carbon dioxide which is carried around to the lungs
   • resynthesis of ATP
     • sufficient energy is released at this stage to resynthesise 2 moles of ATP

2. Electron transport system

   • water (H2O)
     • is formed when the hydrogen ions & electrons combine with oxygen through a series of enzymes reactions
   • resynthesis of ATP
     • majority of energy is released here for the resynthesis of ATP
     • 34 moles of ATP can be resynthesised making this the most efficient source of energy in the body

3. glycogen/glucose

   • process of glycolysis
     • pyruvic acid
       • acetyl COA
         • beta oxidation
         • citric acid
           • Krebs cycle
             • Electron transport chain
               • 34 ATP
               • H2O
             • 2 ATP
       • lactic acid
     • 2 ATP

4. EPOC - excess post-exercise oxygen consumption

   • Fast component
     • restoration of muscle ATP + PC
     • re-saturation of myoglobin with oxgyen
   • Slow component
     • removal of lactic acid
     • maintenance of elevated heart and respiratory rates
     • replenishment of glycogen stores
     • elevated body temperature