ENERGY SYSTEMS Flashcards
What is the ATP-PC energy system
energy system using phophocreatine as its fuel
Define VO2 max
The maximum volume of oxygen that can be taken up by the muscles per minute
DEFINE Sub-maximal oxygen deficit
When there is not enough oxygen available at the start of exercise to provide all the energy (ATP) aerobically
Define EPOC
the amount of oxygen consumed during recovery above that which would have been consumed at rest during the same time
What is the fast component of EPOC?
- The restoration of ATP and phosphocreatine stores and the re-saturation of myoglobin with oxygen
- Complete restoration takes up to 3 minutes but 50% after 30 seconds- 3 litres of oxygen consumed
- after exercise oxygen stores in myoglobin are limited, suplus of oxygen supllied through epoc helps replenish these stores taking 2 minutes
WHY DO WE HAVE AN INSUFFICIENT AMOUNT OF OXYGEN WHEN WE FIRST START EXERCISING FOR ENERGY TO BE PROVIDED AEROBICALLY
- takes time for circulatory system to respond to the increased demand for oxygen and takes mitochondria time to adjust to the rate of aerobic respiration needed
- as a result energy is provided anaerobically at start of exercise until mitochondria and circulatory system can cope, know as sub maximal oxygen deficit
WHAT IS THE SLOW COMPONENT OF EPOC
- Lactic acid accumulated during exercise needs to be removed, takes up to an hour or longer depending on the intensity of exercise
- maintaining breathing and heart rate- requires extra O2 then assist replenishment of atp and phosphocreatine stores, re-saturate myoglobin,
- glycogen restoration- eat carbs
- increase body temperature- extra oxygen from slow component needed to fuel this increase in temperature till body returns to normal
LIST WAYS IN WHICH LACTIC ACID CAN BE REMOVED
- when O2 present, lactic can be converted to pyruvate and oxidised into carbon dioxide and water into inactive organs, can then be used my muscles as energy source
- cori cycle- transported to blood to liver where converted to blood glucose and glycogen
- converted into protein
- removed in sweat and urine
- cool down can accelerate removal, oxygen flushed through quicker
DEFINE LACTATE THRESHOLD
- the point during exercise where lactate quickly accumulates in the blood
WHY DOES LACTATE ACCUMULATION CAUSE FATIGUE
- as lactate accumulates in muscles, more H+ ions present, increases acidity.
- this slows down enzyme activity and breakdown of glycogen which causes muscle fatigue
DEFINE OBLA
- ONSET BLOOD LACTATE ACCUMULATION
- the point where lactate levels go above 4 mlm per second
AS FITNESS INCREASES…
The lactate threshold becomes more delayed
LIST THE FACTORS THAT AFFECT RATE OF LACTATE ACCUMULATION
- Exercise intensity
- muscle fibre type, slow twitch fibres produce less lactate
- rate of blood lactate removal
- fitness of performer, person who trains more will be in better position to delay obla
LIST THE FACTORS THAT AFFECT VO2 MAX
- GENDER
- LIFESTYLE
- TRAINING
- GENETICS
- AGE
DESCRIBE ALTITUDE TRAINING
- partial pressure of O2 drops as altitude increases, usually by up to 50% at an altitude of 5000m.
- therefor ther is reduction in the diffusion gradient between the air and the lungs and between the alveoli and blood.
- means haemoglobin not fully saturated so aerobic performance suffers
