Energy Systems

Energy Systems

1. Role of ATP in exercise

   • Energy obtained from breakdown of food
   • ATP molecule stores & releases energy
   • Formed from ADP & phosphate
   • Energy produced by bond between phosphates
   • Converts ADP to ATP to resynthesise

2. ATP-PC System

   • Sudden & powerful movements
   • Use ATP without oxygen
   • Replenish ATP quick using creatine phosphate
   • PCr bond breaks, energy transfers to ADP resynthesises ATP
   • Highest intensity for 10s
   • Anaerobic, produces 1 ATP

3. Lactate System

   • 2 systems
     • Anaerobic Glycolysis
       • Begins after ATP-PC
       • Breaks down glycogen releasing energy
       • Energy resynthesises ATP
       • Glucose= 2 ATP Glycogen= 3 ATP
     • Lactic Acid Production
       • Limiting factor
       • Accumulates & diffuses into tissues & blood
       • Impedes muscle contraction, causes fatigue
       • Burning sensation with soreness
   • High intensity, short-term
   • Anaerobic, produces 2/3 ATP
   • Carbs convert to glucose stored as glycogen
   • Stored in liver & muscle
   • ATP made by breakdown of glucose & glycogen

4. Aerobic System

   • 3 Systems
     • 1. Aerobic Glycolysis
       • Aerobic metabolism 1st stage
       • Carbs into pyruvic acid
       • Slow to deliver energy
       • Produces 2 ATP
     • 2. Krebs Cycle (citric acid)
       • Aerobic metabolism 2nd stage
       • Takes place in mitochondria
       • Pyruvic acid converted to citric acid
       • CO2 & hydrogen are waste
       • Produces 2 ATP
     • 3. Electron Transport Chain
       • Produces 34 ATP from glucose
       • Hydrogen accepted by hydrogen acceptor in mitochondria
       • Uses oxygen
   • Long-term, with oxygen
   • Glycogen & fatty acids broken down produces CO2 & water
   • Occurs in mitochondria
   • Improved fitness converts food sources easier
   • Slow to engage
   • Long, continuous & moderate exercise
   • Produces total of 38 ATP