8.1 Energy systems Flashcards
What energy type do we use for muscle contractions
Adenosine Triphosphate
What molecules is ATP comprised of
- 1 Adenosine
- 3 phosphates
How is the energy from ATP released
breaking the bonds
What enzyme breaks down ATP
ATPase
What is formed once ATPase breaks down ATP
- Adenosine di-phosphate
- inorganic phosphate (pi)
Chemical reactions in our body are fuelled by what
- food
- Phosphocreatine
Where is phosphocreatine found
Muscles
What are the 3 types of energy systems
- Aerobic
- ATP-PC
- Anaerobic Glycolytic
What energy type will high intensity exercise rely on
anaerobic energy
What are the 2 ways anaerobic energy can be produced
- Anaerobic glycolytic
- ATP-PC
What energy system will be used for low intensity exercise
Aerobic
What does the aerobic system do with glycose
breaks it down into CO2 and H20
What is H20 and CO2 efficient in the presence of (aerobic system)
O2
How many molecules of ATP can be produced when oxidising glucose
38 molecules of ATP
What else other then glucose can be broken down for form energy in the aerobic system
fats (fatty acids)
proteins (amino acids)
The products of fat and protein metabolism are reduced to which molecule
Acetyl coenzyme A
Where does Acetyl Coenzyme A enter
Krebs cycle (stage 2 of aerobic system)
What are the 3 stages of the aerobic system
- Glycolysis
- Krebs cycle
- Electron transport chain
Is glycolysis aerobic or anaerobic
Aerobic
Where does the first stage of the aerobic system take place
Sarcoplasm of the muscle cell
What is Glycolysis
the breakdown of glucose to pyruvic acid
How many molecules of ATP are produced when glucose undergoes glycolysis
2 molecules of ATP
What happens to pyruvic acid before it can enter the next stage
it’s oxidised into 2 acetyl groups and is carried into krebs cycle by coenzyme A
In the 2nd stage of the aerobic system what happens to the 2 acetyl groups
They diffuse into the matrix of the mitochondria
What does the acetyl group do once inside the mitochondria
combines with oxaloacetic acid forming citric acid
what element is removed from citric acid inside to mitochondria
Hydrogen
What happens once Hydrogen is removed from citric acid
it undergoes oxisative carboxylation
What does oxdative carboxylation mean
CO2 is produced through the removal of a C group as a result of oxidation reactions.
what happens to carbon in the krebs cycle
Forms CO2 and is taken to the lungs to be breathed out
What happens to Hydrogen in the krebs cycle
taken to the electron transport chain
How is Hydrogen carried to the electron transport chain
By hydrogen carriers
Where does hydrogen being carried occur
in the cristae of the mitochondria
What happens to hydrogen when inside the mitochondria
Hydrogen splits into hydorgen ions and electrons and they’re charged with potential energy
What happens when the hydrogen ions are oxidised
They form H2O
What do hydrogen electrons do in the electron transport chain
provide energy to resynthesise ATP
What is beta oxidation
fat is broken down into glycerol and free fatty acids for transportation by the blood
When fatty acids undergo beta oxidation what happens
convewrted into acetyl coenzyme A
Which molecules makes more ATP fatty acids or glucose
Fatty acids
why are fatty acids used for long duration low intensity exercise
they produce more ATP per molecule
What are the advantages of the aerobic system
- 36 mole of ATP produced
- no fatiguing by products (CO2 + H2O)
- lots of glycogen and triglyceride stores so exercise can last a long time
What is a disadvantage of the aerobic system (fatty acids)
Fatty acid transportation to the muscles is low and also requires 15% more O2 to be broken down the glycogen
What fuel does the ATP-PC system use
Phosphocreatine (PC)
What is PC
Energy rich phosphate compound found in the sarcoplasm of the muscles
When are our ATP-PC stores used
single maximal movement
What is an example of a sport where we would use our phosphocreatine stores
- Long jump take off
- shot putt
How long can your PC stores last
5-8 seconds
What is the only way you can replenish your PC stores
Low intensity work where O2 is present
Why does Usain Bolts time at the end of the 100m sprint slow down
PC stores run out forcing him to use another source of energy which is slower
is the ATP-PC system aerobic or anaerobic
anaerobic
When does the ATP-PC system re-synthesis ATP
When the enzyme creatine kinase detects high levels of ADP
What does creatine Kinase do
Breaks down the phosphocreatine in the muscles to phosphate and creatine releasing energy
Phosphocreatine (PC) —>
phosphate (pi) + creatine (c) + energy
What is the equation that —> ATP
Energy + Pi + ADP
How much energy is left for when 1 molecule of PC is broken down to form ATP
Enough energy to form 1 molecule of ATP
As the PC system has a 1:1 ratio for producing ATP how efficient is it
Not very efficient
Does the ATP-PC produce any by products
No
How long does it take to replenish 50% of our ATP-PC stores
30s
How long does it take to replenish 100% of our ATP-PC stores
3 mins
How can you extend the time the ATP-PC system is utilized for
Creatine supplementation
What does the anaerobic glycolitic system depend on for it’s duration
The fitness of the individual
How high the intensity of the exercise is
What is activated when the PC stores are low
the enzyme glycogen phosphorylase
During anaerobic glycolysis how many ATP molecules are produced per glucose molecule
2 ATP/1 glucose molecule
2 of those are used to provide energy for glycolysis
What is the anaerobic glycolytic system also known as
lactate system
What intensity activity is the anaerobic glycolytic system used for
High intensity exercise
How long does the anaerobic glycolytic system last for
3 mins and peaks at 45 seconds
Advantages of the anaerobic glycolitic system
- ATP can be resynthesised quickly
- lactic can be converted to liver glycogen with O2 present
- Can be used for a sprint finish
Disadvantages of the anaerobic glycolitic system
- Lactic acid is a by-product
- lactic acid denatures enzymes
- small amounts of energy released from glycogen under anaerobic conditions
What is the energy continuum
describes which energy system is used for different types of physical activity
What energy systems are used for physical activity that lasts for 90s - 3 mins
anaerobic glycolytic and ATP-PC
For type 1 muscle fibres what is their main energy system
Aerobic
How many molecules of ATP can a type 1 muscle fibre produce
36
For a type 1 muscle fibre is the ATP production fast or slow
Low but they’re less likely to fatigue
What is VO2 max
The maximum volume of O2 that can be taken up by the muscles per minute
What is submaximal O2 deficit
When there is not enough O2 available at the start of exercise to provide all the energy aerobically
What is EPOC
The amount of O2 consumed during recovery above that which would have been consumed at rest during the same time
What are the 2 components of EPOC
Fast component
Slow component
What is O2 consumption
That amount of O2 we use to produce ATP
What is O2 consumption also referred as
VO2
How much O2 do we consume at rest
0.3-0.4 litres per minute
What is the maximal amount of O2 consumption
3-6 litres per minute
What does MAOD refer to
Maximum accumulated oxygen deficit
What does MAOD give an indication to
Anaerobic capacity
What is breathlessness after exercise referred as
EPOC
How many days after a marathon may it take to replenish glycogen
several days
How does the fast component restore ATP and phosphocreatine
Uses extra O2 that’s been taken in during recovery
What does the fast component re saturate myoglobin with
O2
How long does it take the fast component to re saturate phosphocreatine
3 mins
How long does it take the fast component to re saturate phosphocreatine to 50%
30 seconds
How many litres of O2 are consumed for the replenishment of phosphocreatine
3 litres
Where does myoglobin store O2
In the sarcoplasm that’s diffused from haemoglobin
How long does it take the surplus of O2 supplied through EPOC to replenish O2 stores
2 mins using 0.5 litres of O2
How long does it take to recover from lactic acid
1 hour or longer depending on the exercise intensity
What are the 3 ways lactic acid can be removed
Sweat urine
Converted into protein
the cori cycle
What is the cori cycle
lactic acid is transported into the blood to the liver where it is converted to blood glucose and glycogen
How is lactic acid removed when O2 is present
converted back into pyruvate and oxidised into CO2 and H2O in inactive muscles and organs
Can muscles use lactic acid as an energy store
Yes
Where is the majoirty of the lactic acid oxidised
mitochondria
How does doing a cool down help with the removal of lactic acid
keeps metabolic rate of muscles high
keeps capillaries dilated allowing O2 can be flushed through removing lactic acid
When does the slow replenishment stage occur
as soon as lactic acid appears in the muscle
How many litres of O2 is used in the first half hour of recovery
5-6 litres removing 50% of lactic acid
What does maintaining breathing and heart rate require and what for
extra O2 to provide energy needed for respiratory and heart muscles
Extra O2 is used for ATP and phosphocreatine replenishment
How can you accelerate glycogen restoration
high carb meal
eating within 1 hour of exercise
What is the 1st nutritional windows for optimal recovery after exercise
cars and proteins should be consumed in a 3:1 4:1 ratio
What’s the 2nd nutritional window for optimal recovery after exercise
1-3 hours after exercise a high protein carb and healthy fat should be consumed
Why after exercise should carbs and proteins be consumed in a 3:1 or 4:1 ratio
helps body re-synthesis muscle glycogen more efficiently then just consuming carbs on their own
What is an example of an athlete consuming carbs and protein after exercise
- Milkshake
- Protein shake (recovery shake)
What happens to respiratory temp when body temp remains high
Respiratory rate remains high allowing performer to take in more O2
What is needed to fuel the increase in temp in the body
Extra O2 from (slow component)
Why isn’t the aerobic system good at producing energy rapidly
it’s to complicated
Why can an 800m runner be more likely to run the race again
They’re mainly using their anaerobic glycolytic system
demand for energy is less
use the system for longer
Why would a 400m runner be less likely to run the race again
high intensity of using anaerobic glycolytic system
be exhausted due to the build up of lactic acid
Are lactate and lactic acid the same thing
No
What is the by product of anaerobic glycolytic system
lactic acid as the result of glycolysis
Is more or less lactic acid produced at higher intensity exercise
More is produced
What does lactic acid produce when being broken down
H+ ions
After H+ ions are released from lactic acid being broken down what does the remaining compound combine with
sodium ions or potassium ions to form the salt lactate
Where does lactate accumulate
in the muscles
What does more H+ ions slow down
enzyme activity affecting the break down of glycogen
What happens to lactate produced in the muscles
diffuses into the blood and blood lactate an be measured
What is lactate threshold
the point in exercise where lactic acid quickly accumulates in the blood
When will you experience the lactate threshold
crossing the aerobic and anaerobic threshold
When is lactate procued
It’s always being produced only in small amounts
What happens to OBLA as exercise intensity increases
body can’t produce enough O2 to breakdown lactate
How many millimoles can be found in the blood at rest
aprox 1-2 millimoles/litre
How many millimoles can be found in the blood during exercise
aprox 4 millimoles/litre
What is lactate threshold expressed as
A percentage of VO2 max
What would the lactate threshold be a percentage of VO2 max for average performers
50-60 percent of their VO2 max
What would the lactate threshold be a percentage of VO2 max for elite performers
70, 80 or 90 percent of their VO2 max
What is fatigue caused by when working below the lactate threshold
Lactate
Would you have a higher or lower lactate threshold if you were fitter
Higher
What is a fitness test to illustrate OBLA
Multistage fitness test
How does the multistage fitness test, test your lactate thresholds
- Becomes increasingly harder untill performer can no longer provide energy aerobically
- producing lactate causing fatigue
What are the factors affecting lactate accumulation
- Exercise intensity
- muscle fibre type
- rate of blood lactate removal
- respiratory exchange ratio
- fitness of the performer
How does the indirect calorimetry work
estimate of energy expenditure through gaseous exchange
What does the calorimetry measure
how much CO2 is produced and how much O2 is consumed at rsting and aerobic exercise
What does calculating the gas volumes help us find out
The main substrate being used (fat or carbohydrate)
What does the indirect calorimetry allow us to calculate
VO2
VO2 max
What does measuring energy expenditure allow us to do
how intense exercise is
identify levels of fitness
effectiveness of training programme
highlight dietary requirements (recovery)
Which sports use lactate sampling
running
swimming
rowing
What does lactate sampling involve
taking tiny blood sample and a hand held device indicating how much lactate is present
What does lactate sampling allow
idea of fitness level
select training zones
What does it mean if the test results show a lower lactate level at the same exercise intensity
performer has an increase in peak speed/power
time to exhaustion
improved recovery heart rate
higher lactate threshold
What is most used to estimate VO2 max
Multistage fitness test
Harvard step test
coopers 12 minute run
What is done to measure VO2 max
direct gas analysis
What is involved in a direct gas analysis
increasing treadmill intensities
cycle ergometer
rowing machine
When performer is running on a treadmill what does the computer calculate for VO2 max
volume and concentration of O2 in expired air is measured and compared to % of O2 in atmospheare
What is the respiratory exchange ratio
The ratio of CO2 produced compared to O2 consumed
What is RER used to measure
exercise intensity
What information does RER provide
Fuel usage dring exercise
What energy sources can be oxidised
- Carbs
- fats
- protein
What will calculating the RER allow you to see
Which energy sources are being oxidised hence if the performer is working an or aerobically
What is the RER equation
O2 consumed per min
If the RER value is 1 what energy source would the performer be using
Carbs
If the RER value is 0.7 what energy source would the performer be using
fats
If the RER value over 1 what energy source would the performer be using
anaerobic so more CO2 produced then O2 consumed
Does the percentage of O2 change at sea level and altitude
No the partial pressure of O2 drops at altitude
As the partial pressure of O2 drops what happens to the diffusion gradient
reduction in the diffusion gradient between air and lungs and between alveoli and blood
What effect does the reduction on the concentration gradient have on the blood
Less O2 so Hb isn’t as saturated
How does less O2 in the blood affect the muscles
quicker onset anaerobic respiration
decreases aerobic performance and VO2 max
How high above sea level does Altitude training take place
2500m
How long do the affects of altitude training last
14 days
What are the benefits of altitude training
- Inncreased number of RBC and conc of Hb
- increase in capillarisation and EPO
- enhanced O2 transport
- increased lactate tolerance
How many weeks do you have to do altitude training for before you realise any benefits
several weeks
What are the negatives of altitude training
- altitude sickness
- difficult to train at same intensity as PP of O2 is lower
- loss of fitness
- benefits lost quickly
- psychological issues
Is HIIT aerobic or anaerobic
Btoh
What are the 4 variables of HIIT
- Duration of work interval
- Intensity/speed of interval
- duration of the recovery interval
- number of work intervals and recovery intervals
What does HIIT involve
Short intervals of max intensity followed by recovery interval of low to moderate intensity exercise
What energy system should you be using during the work period
Anaerobic
What energy system should you be using during the recovery period
aerobic
What does HIIT improve
Fat burning potential
glucose metabilism
aerobic and anaerobic endurance
What are the 3 varitations of HIIT
- high intensity work and low intensity recovery
- different lengths of time for the work and recovery intervals
- different exercise intensity for the recovery interval
