energy sources and systems
- Glucose – a carbohydrate, the main form of carbohydrate found dissolved in plasma and used as an energy source to resynthesize ATP by cells and muscles.
- Glycogen – a carbohydrate, the stored form of carbohydrate that is found in muscles and the liver used as an energy source.
- Triglycerides and fats – main form of stored fat used as a source.
- Protein and lactate.
· Effects of high intensity activity on ATP and PC stores
- ATP and PC levels decrease during exercise.
- Insufficient Stores don’t fully recover and there is not enough ATP and PC being resnythesised in 30 seconds of rest.
- During exercise ATP / PC is supplying energy, where the PC breakdown is for ATP resynthesis.
- Then during recovery ATP / PC is resynthesized, but 30 seconds is insufficient recovery time to fully replenish as it takes 2-3 minutes for full recovery.
· Energy sources and level of intensity
- At low level of exercise energy comes from a mixture of fats and carbohydrates.
- These are broken down aerobically, using oxygen and the aerobic system.
- Glycolysis occurs to break glucose down, into pyruvate.
- Beta oxidation breaks down tri-glycerides.
- The Krebs cycle involves the oxidation of acetyl-coenzyme-A and citric acid production.
- In the Electron transfer chain, water is formed with hydrogen ions.
- At high levels of intensity carbohydrates are only energy source and as intensity increases, more carbohydrates are used.
- At high intensities fat use is limited by oxygen availability as no fats used anaerobically.
- Energy release from fats is slower / quick release of energy from carbohydrates.
- Lactic Acid System has no oxygen and anaerobic glycolysis occurs, where glucose is broken down forming pyruvate and lactic acid formed.
the atp system
· Adenosine triphosphate.
· Immediately useable energy source for the first 0-2 seconds of exercise.
· ATP à ADP = P = ENERGY
· Breaking bonds creates energy.
the atp-pc system
· ATP-PC system
- Uses phosphocreatine.
- PC à P + C + ENERGY
- Breaking bonds creates energy.
- Producing enough energy to resynthesize two molecules of ATP.
- Used for the first 2 to 8 seconds of exercise.
- PC stores take 3 minutes to replenish
· Cons of PC the system
- Limited stores of PC.
- High intensity exercise can only be completed for brief period of time (8 – 10 seconds.)
- Full recovery takes up 2-3 minutes.
· Pros of the PC system
- Energy is released quickly and doesn’t require oxygen.
- ATP is resynthesised quickly and the phosphocreatine stores recover quickly.
- This allows high intensity exercise to…