energy systems Flashcards
how long does the ATP-PC system last for
8-10seconds
for every one molecule of PC broken down how many ATP are produced ?
theres enough energy to produce one ATP molecule
how long does it take to recover the pc system after its been fully used
2-3mins
but could recover 50% of the stores in 30 seconds
what are the 3 advantages of the ATP-PC system
1- no fatiguing by products
2- possible to extend time of system by taking creatine
3- ATP and PC can be resynthesized quickly
what are the 3 disadvantages of the ATP-PC system
1- energy only lasts for ten seconds
2-only 1 molecule of ATP can be resynthesized for PC
3- replenishing PC must take place in the presence of oxygen
how does the ATP-PC system provide energy
A-P-P P - one phosphate is released to provide energy creating ADP
what happens to phosphocreatine in the ATP-PC system
creatine and phosphate split to provide energy to convert ADP to ATP
what enzynme breaks down PC
creatine Kinase
whta is the equation to resyntheiss ATP
ADP+P+ENERGY= ATP
where is ATP resynthesized
Sarcoplasm
what are the advantages of ATP-PC system
- no fatiguing by products
- it is possible to extend the time of the system by taking creatine
- ATP can be resynthesized quickly
- PC can be resynthesized quickly
what are the disadvantages of ATP-PC system
- energy only lasts 10 seconds
- only one molecule of ATP can be resynthesized for 1 PC
- replenishing PC must take place in the presence of 02
what sports / environment is the aerobic system suited to
when exercise intensity is low and 02 supply is high = cross country
how many molecules of ATP can be produced in the aerobic system
38
what are the 3 stages of the aerobic system
glycolysis , kerbs cycle and electron transport chain
what is glycolysis
process in which glucose is converted into pyruvate to produce energy.
where does glycolysis take place
in the sarcoplasm of the muscle cell
1 molecule of glucose = ATP?
2 ATP
what is the last step in the glycolysis stage
the pyruvate acid then can enter Krebs cycle . it is oxidised into 2 acetyl groups and carried into Krebs cycle by co enzyme A
what is the krebs cycle
a series f cyclical chemical reactions that take place using oxygen in the matrix of the mitochondria in the muscle
what happens in the Krebs cycle
acetyl groups combine with oxaloacetic acid, forming citric acid and the rearranged form of citric acid undergoes oxidative carboxylation which means that it gives of hydrogen and carbon dioxide.
where does the carbon dioxide go from Krebs cycle
goes to the lungs and is expired
where do they hydrogen ions go from krebs cycle
move forward into the electron transfer chain
what is the electron transport chain
involves a series of chemical reactions in the cristate of the mitochondria where hydrogen is oxidised to form water
how many ATP are produced in the electron transport chain
34
how does the energy get produced in the electron transport chain to resynthesize ATP
the hydrogen electrons are charged and and provide the energy
what is beta oxidation
stored fat is broken down into glycerol and free fatty acids for transportation by the blood
what happens during beta oxidation
fatty acid are converted to acetyl coenzyme A through beta oxidation and this is the entry molecule for the Krebs cycle this then follows the same cycle as glycogen.
what type of exercise and intensity is fats used for
long duration and low intensity
what are the advantages of the aerobic system
- more ATP can be produced up to 38 ATP
- there are no fatiguing by products
- lots of glycogen and triglyceride stores so exercise can last for a long time
what are the disadvantages of the aerobic system
1.cannot be used straight away takes a while to build up enough 02 to break down the glucose and fatty acids
2. fatty acid transportation to muscles is low and also requires 15% more o2 to be broken down than glucose
what is the average amount of o2 we use to produce ATP - referred to as vo2
at rest = 0.3 to 0.4l/m
what happens to the amount of o2 consumed when intensity increases
the amount of o2 consumed increases until maximum vo2 is reached this can be 3-6 L/M
what is a sub maximal oxygen deficit
when there is not enough oxygen available at the start of exercise to provide all the energy ATP aerobically
what is a maximum oxygen deficit
gives an indication for anaerobic capacity
what are the 4 functions of the slow component of EPOC
- removal of Latic acid
- to maintain BR and HR
3.glycogen replenishment
4.increase body temp
what is the fast component of EPOC
extra o2 is consumed during recovery is used to restore ATP and phosphocreatine and to desaturate myoglobin with o2
EPOC
how long does it take to completely restore phosphocreatine
3 mins but 50% can be replenished in 30 secs during which time 3 litres approx. of o2 is consumed
EPOC
what happens to myoglobin stores after exercise
stores are limited
EPOC
how are myoglobin stores replenished after exercise
the surplus of o2 supplied during EPOC helps to replenish these stores , taking up to 2 minutes and using approx. 0.5L of o2
how is Latic acid removed from the body- 4 ways
1- when o2 is present Latic acid can be converted back into pyruvate and oxidised into co2 and h2o in the inactive muscles and organs - this can then be used by the muscles as an energy store
2- transported in the blood to the liver where it is converted to blood glucose and glycogen (cori cycle)
3- converted into protien
4- removed in sweat and urine
what can be done to accelerate the removal of Latic acid
a cool down as it can be oxidised in the mitochondria
when does the slow replenishment stage of recovery start to remove Latic acid
as soon as Latic acid appears in the muscle cells and will continue using breathed oxygen till recovery is complete
how much o2 is required to remove latic acid
5-6L of o2 in the 1st half an hour or recovery removing 50% of the Latic acid
EPOC
- how is glycogen replenished 2 ways
1.a lot of glycogen can bd restored as Latic acid is converted back to blood glucose and glycogen in the liver via cori cycle
2.eating a high carb meal will accelerate glycogen restoration , as well as eating within 1 hour of exercise
EPOC
- what are the 2 nutritional windows for optimum recovery
- 30 minutes after exercise
carbs to protein
3;1/4;1 - 1-3 hours after exercise increase the amount of protein , carbs and healthy fats
why does body temp increase during exercise
when body temp increases - respiratory rates increase wich helps the performer take in more o2 during recovery
extra o2 is needed to fuel the increase in temp until the body returns to normal
what does latic acid release and what does the remainder form
hydrogen ions and the remaining bit of acid joins with sodium to form salt=lactate
finish the sentence - the higher the intensity of exercise the ….. Latic acid is produced
the more latic acid is produced
what happens as lactate accumulates in the muscles
more hydrogen ions are present and this will increase the acidity inside the muscles
what does and increased acidity inside the muscles mean
slowing down of enzyme activity = effect on breakdown of glycogen leading to muscle fatigue
what system does the body work as lactate accumulation increases
the body moves away from work aerobically and starts to work anaerobically
what is the corssing of working aerboically to anerobically called
lactate threshold
what is the lactate threshold
where Latic acid rapidly accumulates in the blood (an increase in 2 millimoles per litre of blood above resting levels )
why do we constantly produce small amount of lactate
due to red blood cell activity at low intensity - but the body is able to deal with these low levels
what is OBLA(onset blood lactate accumulation)
when the intensity of exercise increases so the body is unable to produce enough oxygen to breakdown lactate so levels build up
how is the lactate threshold measured
as a percentage of VO2 max
define VO2 max
the maximum volume of o2 that can be taken up by a muscle per minute
what is the average performers lactate threshold as a percentage of VO2 max
50-60%
what is the elite performers lactate threshold as a percentage of VO2 max
70-80%
what is the main difference in performance when it comes to the lactate threshold
comes from the delayed lactate threshold as fatigue is caused by lactate and this decreases performance
what are the 5 factors affecting VO2 max
1- Exercise intensity
2- muscle fibre type
3- rate of blood lactate removal
4- the respiratory exchange ratio
5- the fitness of the performer
how does the intensity of exercise affect the rate of lactate accumulation
higher the intensity of exercise , the greater the demand for energy (ATP) and the faster OBLA occurs
how does the muscle fibre type affect the rate of lactate accumulation
fast twitch fibres for high intensity exercise and can only maintain their workload with the use of glycogen as a fuel. when glycogen is broken down without o2 into pyruvic acid Latic acid is formed = fatigue
slow twitch fibres produce less lactate then fast. when slow twitch uses glycogen as a fuel , due to presence of o2 the glycogen can be broken down effectively with little lactate production
how does the rate of blood lactate removal affect the rate of lactate accumulation
if the rate of lactate removal is equivalent to the rate of lactate production then the concentration of blood lactate remains constant. If lactate production increases then lactate will start to accumulate in blood until OBLA is reached
how does the respiratory exchange ratio affect the rate of lactate accumulation
the ratio of CO2 produced compared to o2 consumed. As this ratio has a value close to 1:0 glycogen becomes the preferred fuel and there is a greater chance of the accumulation lactate
how does the fitness of the performer affect the rate of lactate accumulation
more regular training = delay OBLA a bit as adaptations occur to trained muscles.
increased numbers of mitochondria and myoglobin together with an increase in capillary density improve the capacity for aerobic respiration and therefore avoid the use of lactate anaerobic system
what is special with elite performers with power and sprinters with lactate
elite sprinters and power athletes will have a better anaerobic endurance than non elite
their body has adapted to cope with higher levels of lactate
what is buffering to do with lactate
a process wich aids the removal of lactate and maintains acidity levels in the blood and muscle
buffering increases the rate of lactate removal
more exercise = elite athletes have better buffering so elite athletes can work harder for longer before fatigue sets in
what are the 7 factors affecting VO2 max
1- physiological
2- lifestyle
3-body composition
4- gender
5-age
6- genetics
7- training
what physiological factors affect VO2 max
increased maximum cardiac output
increased stroke volume and ejection fraction
increase lactate tolerance
increase myoglobin content increased red blood cell and haemoglobin
how does lifestyle affect VO2 max
smoking , sedentary lifestyle poor diet and poor fitness can all reduce V02 max
how does body content affect VO2 max
increased percentage of fat decreased VO2 max
how does gender affect VO2 max
men have 20% increased V02 max than women
how does age affect VO2 max
older=VO2 max decreases as body systems become less efficient
how does gender affect VO2 max
inherited factors of physiology limit possible improvement
how does training affect VO2 max
VO2 can be improved by 10-20% following a period of aerobic training, continuous , fartlek, and aerobic
what is lactate sampling
monitors training and predicts performance.
small blood sample - indicates the presence of lactate
can help to select training zones to get the desired effect which is delayed lactate threshold
how often is lactate sampling done
intervals throughout performance
what is indirect calomitry to do with lactate accumulation
measures how much CO2 is produced and how much 02 is consumed at both rest and during aerobic exercise
calculating the gas volumes also enables us to find out the main substrate being used - fats/carbs
very reliable - precise calculation of VO2 max
VO2 max tests to do with lactate there are 3
multistage fitness test - BEEP
cooper 12 min run
Harvard step test
how does the VO2 max test work
measures the concentration of O2 that is inspired and the concentration of CO2 expired
What is the equation for RER
CO2 expired per min/ 02 consumed per min
what does each value of RER mean
1
0.7
less than 1
RER that is 1 = performer using carbs
RER of approx. 0.7= performer using fats
RER less than 1 = anaerobic respiration more CO2 is produced than 02 consumed
What is the RER test
determines what energy source is being oxidised and if their working aerobically or anaerobically.
measures rate of CO2 produced compared to 02 consumed
