Energy systems

Energy systems

1. ATP-PC

   • Anaerobic
   • Fuel= phosphocreatine
   • Site = Sarcoplasm
   • Enzyme = creatine kinase
   • 1 mole of ATP produced
   • No by-products formed
   • High intensity for 2-10 seconds
   • Stages
     • High intensity exercise triggers creatine kinase catalysing the break down of PC
     • Break down of PC releases a free phosphate which can be resynthesised
   • Advantages/ Disadvantages
     • Disadvantages
       • Low ATP yield and small pc stores lead to rapid fatigue
     • Advantages
       • No delay waiting for o2
       • Pc readily available in muscle cell
       • Simple and rapid breakdown
       • Quick provider of energy
       • No fatiguing by products

2. Aerobic Energy system

   • Aerobic
   • Fuel = Glycogen/Glucose / Fat
   • Enzymes
     • Phosphofructokinase
     • Acetyl CoA
   • Site Stage 1- sarcoplasm Stage 2 - Matrix in the mitochondria Stage 3 Cristal in the mitochondria
   • 38 ATP Molecules produced
   • C6H12O6 +6CO2 —> 6H2O+ 6O2
   • By products are water +oxygen
   • Low - moderate intensity for above 3 minutes
   • Advantages/ Disadvantages
     • Advantages
       • High yield for longer periods of time
       • No fatiguing by products
     • Disadvantages
       • Delay for oxygen due to complex reactions
       • Slow production of energy limits to sub max intensity
       • Free fatty acids demand 15% of o2 for breakdown
   • Stages
     • Aerobic Glycolysis
       • Glucose into pyruvic acid. PFK catalysed and generates 2 Moles ATP. Oxygen in supply so moves into linked reaction which co enzyme A catalyses producing Acetyl CoA
     • Kreb Cycle
       • Acetyl CoA combines with oxaloacetic acid to form critic acid, co2 and hydrogen. Energy resynthesises ATP
     • Electron transport chain
       • Hydrogen atoms carried through ETC by NADS and FADS splitting into hydrogen atoms and hydrogen ions
       • Hydrogen ions are oxidised and removed as H2O
       • Hydrogen atoms carried by NADS resynthesise 30 Moles of ATP and those carried by FADS resynthesise 4 Moles

3. Glycolytic System

   • Anaerobic
   • Fuel = Glycogen/ Glucose
   • Takes place in the sarcoplasm
   • Enzymes
     • Glycogen Phosphorylase (GPP)
     • Phosphofructokinase (PFK)
     • Lactate Dehydrogenase (LDH)
   • 2 Moles ATP produced
   • C6H12O6 -> C3H6O6
   • High intensity
     • 3 minute
   • Lactic acid formed
   • Advantages/ disadvantages
     • Advantages
       • No delay waiting for O2
       • Large fuel source stored in liver,blood stream, muscle cell
       • High intensity exercise for 3 minutes
       • Lactic Acid recycled in another system to provide More energy
     • Disadvantages
       • By-Product lactic acid results in fatigue and reduced PH/ enzyme activity
       • Relatively low ATP yield and lengthy recovery
   • Stages
     • Kicks in after 10 seconds of pc stores depleted. PFK triggered catalysing the breakdown of glucose. When glucose levels drop GPP released catalysing the break down of glycogen into glucose
     • Anaerobic Glycolysis Break down of glucose into pyurvic acid. 3 minute resynthesis but peaks at 1 minute and slowly decreases.
     • At high intensity, o2 not available to break down pyrivic acid so LDH is released and pryuvic acid is converted into Lactic acid