LEWIS: Energy systems Flashcards
Anaerobic energy systems:
ATP stores
ATP-PC
Lactic acid
Site of reaction for ATP stores:
Sarcoplasm (all living cells)
Fuels used for ATP stores:
ATP
Active enzymes for ATP stores:
ATPase
Molecules of ATP produced:
1
Advantages of ATP stores:
Instant high intensity energy sources
Drawbacks of ATP stores:
Only lasts a couple of seconds of intense exercise
Training methods to improve ATP stores:
- High intensity Plyometrics
- High intensity Strength/weight training (80% 1RM)
Adaptations following training on ATP stores:
Increased ATP stores
Sports using ATP stores:
Shot putt
Weight lifting
Site of reaction for ATP-PC energy system:
sarcoplasm
Fuels used in ATP-PC energy system:
Phosphocreatine (PC)
Active enzymes for ATP-PC energy system:
Creatine kinase
Molecules of ATP produced for ATP-PC energy system:
1
Advantages of ATP-PC energy system:
- Quickly resynthesises ATP
- No fatigue by-product
- Phosphocreatine stores restore quickly
- Can extend time through creatine supplementation
Drawbacks of ATP-PC energy system:
- Lasts 8-10 seconds of maximum effort
- PC is very limited within muscle
- PC can only be replenished when there is sufficient energy available in the body (aerobic pathway)
Training methods to improve ATP-PC energy system:
High intensity plyometrics
High intensity weight training
High intensity interval training
Adaptations following training on ATP-PC energy system:
- Increased PC stores
- Increased enzymes for anaerobic
- Greater power output
- Delay in ATP-PC to lactic threshold
- More energy available more rapidly
Sports using ATP-PC energy system:
- 100m sprint
- high intensity activities lasting less than 10 seconds
Site of reaction for lactic acid system:
Sarcoplasm
Fuels used for lactic acid system:
glycogen/glucose
Active enzymes for lactic acid system:
glycolytic enzymes
Molecules of ATP produced for lactic acid system:
2
Advantages of lactic acid system:
- lasts 30-60 seconds
- can last up to 3 minutes depending on intensity
- releases energy quite quickly
- can supply energy in high intensity, short-term activities
- presence of oxygen, lactic acid can be converted back into liver glycogen or used as a fuel through oxidation into CO2 and H2O
- Can be used for a sprint finish at very end of aerobic events where intensity increases (e.g. 5000m)
Drawbacks of lactic acid system:
- lactic acid as fatigue by-product
- Higher fatigue
- increased acidity, due to LA, denatures enzymes and prevents them from increasing the rate at which chemical reactions occur
- Muscle action = inhibited
- Oxygen debt
Training methods to improve lactic acid system:
- High intensity circuit, fartlek training
- Moderate-high intensity interval
- Endurance weight training (60-80% max HR)
Adaptations following training to LA system:
- Increase OBLA, enabling workout at higher level
- Produce more glycolytic enzymes
- Increased VO2 max
Sports using LA system:
- 400m run/hurdler
- 100m swim
- high intensity activities with a duration of approx. 1 minute
Aerobic energy system =
aerobic energy system
Site of reaction for aerobic energy system:
glycolysis = sarcoplasm
Krebs cycle = matrix of mitochondria
ETC = cristae of mitochondria
Active enzymes in aerobic energy system:
KC = Lipoprotein lipase
PROCESS OF BETA OXIDATION
Molecules of ATP produced in aerobic energy system:
G=2
KC=2
ETC=34
OVERALL = 38
Advantages of aerobic energy system:
- 38 ATP molecules produced from glucose/glycogen molecule
- Slow twitch fibres provide a continuous supply of energy over a long period of time
- No fatigue by-products
- Large stores of glycogen and triglycerides - long duration
Fuels used in aerobic energy system:
G = Glycogen/glucose
KC=Fatty acids
Drawbacks of aerobic energy system:
- Requires oxygen = lower intensity/3 minute threshold
- Relies heavily on glycogen stores initially
- Many reactions = while for oxygen to become available to meet the demands of the activity and to ensure glycogen and fatty acids are completely broken down
- Fatty acid transportation to muscles is low and requires 15% more oxygen to be broken down than glycogen
Training methods to improve aerobic energy system:
- continuous training (60-80% max HR)
- low intensity fartlek training
Adaptations following training to aerobic energy system:
- Beta oxidation =more efficient
- Increased oxidative (aerobic) enzymes
- Greater ability to store muscle glycogen
- Increased store of triglycerides
Sports using aerobic energy system:
- marathon
- 1500m
- low-intensity activities with a duration of longer than 1-2min
Beta-oxidation is the process where fatty acids are broken down int he mitochondria to generate acetyl-CoA, the entry molecule for the
Krebs cycle
More ATP can be made from 1 mole of fatty acids than from one mole of glycogen, reason why the predominant energy source in long-duration exercise is
fatty acids
Process of ATP-PC system:
Anaerobic
PC is stored in the muscles and is broken dow to creatine and phosphate by the enzyme creatine kinase… as a result
energy is released for ATP re-synthesis
Process of lactic acid system:
Anaerobic
Glycolysis (glycogen broken down using glycolytic enzymes and is then broken down into pyruvic acid. In the absence of oxygen, the pyruvic acid is converted to lactic acid and
2 molecules of ATP are produced
Process of aerobic energy system:
3 stages:
glycolysis
Krebs cycle
Electron transfer chain
Glycolysis: glycogen is broken down into glucose which is then broken down into
pyruvic acid
Krebs cycle: pyruvic acid diffuses into matrix of mitochondria and a complex cycle of reactions occurs. The reactions result in the production of 2 molecules of ATP and CO2 and hydrogen. The CO2 is breathed out and the hydrogen is taken to the
ETC
ETC: Hydrogen from KC carried by hydrogen carriers. Occurs in the cristae of the mitochondria and the hydrogen splits into hydrogen ions and electrons. They are charged with potential energy. The hydrogen ions are oxidised to form water while the hydrogen electrons provide the energy to
re-synthesise ATP - 34 molecules of ATP produced
