Energy Flashcards
Name 4 features of ATP.
- Only usable source of energy for muscle movement.
- Stored within the muscle cell.
- Can only store small amounts, to last up to 2 seconds of exercise.
- Has to be broken down in the presence of ATPase to supply energy.
Define power.
- Rate at which we can work.
- Measured in watts.
Define energy.
- Ability to perform work or put mass into motion.
- Measure in joules.
Define work.
- Ability to apply force over a distance.
- Measured in newtons.
What are the 3 types of energy?
- Kinetic (movement)
- Chemical (food/glycogen)
- Potential (stored)
What does ATP stand for?
Adenosine Triphosphate
How is ATP broken down?
ATP (broken down by ATPase) = ADP + P + E
How is ATP resynthesised?
E + P + ADP = ATP
What 3 energy systems resynthesise ATP?
ATP/PC
LA
Aerobic
What is an endothermic reaction?
A chemical reaction that requires energy to be added for it to progress.
What is an exothermic reaction?
A chemical reaction that releases energy as it progresses.
What is a coupled reaction?
- Where reactions are linked, you got one endothermic one and one exothermic reaction and they are reliant upon each other.
- The products of one reaction are then used in another reaction.
Give an example of a coupled reaction.
PC (creatine kinase) - C + E + P (exothermic)
E + ADP + P - ATP (endothermic)
Outline the ATP/PC system.
PC is broken down by creatine kinase to produce P + C + energy.
Where does the reaction in the ATP/PC system take place?
Sarcoplasm.
How long does the ATP/PC system last for?
Up to 10 seconds.
Give an example of when the ATP/PC system might be used in sport.
Sprinting for an interception in netball.
State 7 positives of the ATP/PC system.
- Doesn’t require oxygen.
- PC stored in muscle cell as readily available energy source.
- Simple compound so very quick resynthesis of ATP.
- Automatically stimulated by a decrease in ATP and an increase in ADP.
- Provides energy for explosive high-intensity exercise and movements.
- No fatiguing by-products.
- PC can itself be quickly resynthesised so recovery time is quick.
State 3 negatives of the ATP/PC system.
- Only small amounts of ATP and PC stored in muscle cells.
- 1 PC resynthesises 1 ATP.
- Only provides energy to resynthesise ATP for up to 10 seconds.
Outline the LA system.
Glycogen (GPP) Glucose (PFK) - 2 ATP resynthesised Pyruvic acid (LDH) Lactic acid
What 4 effects does lactic acid have on the body?
- Stimulates pain receptors
- Inhibits enzyme action
- Lowers pH
- Causes fatigue
Where does the reaction for LA system take place?
Sarcoplasm
How long does the LA system provide energy for?
10-180 seconds
Give an example of when the LA system might be used in sport.
400m
State 6 positives of the LA system.
- Large glycogen store in muscle/liver is readily available as a potential energy source.
- Resynthesis of 2 molecules of ATP - more than the ATP?PC system.
- Requires fewer reactions than the aerobic system so provides a quicker source of energy.
- GPP and PFK enzyme activation due to a decrease in PC.
- Provides energy for high-intensity exercise lasting between 10-180 seconds.
- Can work aerobically and anaerobically.
State 5 negatives of the LA system.
- Not as quick as ATP/PC system.
- Produces LA - fatiguing by product.
- Reduces pH which inhibits enzyme action.
- Stimulates pain receptors.
- Net effect is muscle fatigue and pain.
What are the 3 stages of the aerobic system?
Aerobic glycolysis
Kerb’s cycle
ETC (electron transport chain)
Outline the aerobic glycolysis stage of the aerobic system.
Glycogen (GPP) Glucose (PFK) - 2 ATP Pyruvic acid \+ Coenzyme A = Acetyl coA
Where does aerobic glycolysis take place?
Sarcoplasm
Outline the Kreb’s cycle stage of the aerobic system.
Acetyl coA \+ Oxaloacetic acid = Citric acid (which enters the kreb's cycle) Kreb's cycle: 1. 2 ATP resynthesises 2. Hydrogen removed 3. CO2 produced and removed 4. Oxaloacetic acid regenerates
Where does the Kreb’s cycle stage take place?
The matrix of mitochondria
Outline the ETC stage of the aerobic system.
H \+ NAD & FAD = NADH & FADH Hydrogen passes down the cristae folds, losing an electron, creating a positive hydrogen ion. Results in: 34 ATP H+O2=H2O
Where does the ETC stage take place?
The cristae of mitochondria
State 5 positives of the aerobic system.
- Large potenital glycogen and free fatty acids (FFA) stores available as an efficient energy fuel.
- Efficient ATP resynthesis when good oxygen supply guarantees breakdown of FFAs.
- Large ATP resynthesis: 38 ATP from one molecule of glucose compared to 2 ATP from LAS and 1 from ATP/PC.
- Provides energy for low/moderate intensity and long duration exercise.
- No fatiguing by products as CO2 and H2O are easily removed.
How long does the aerobic system supply energy for?
3 minutes - 2 hours
Give an example of when the aerobic system would be used in sport.
1500m
Marathon
State 4 negatives of the aerobic system.
- Slower rate of ATP resynthesis compared with system due to the requirement of an increased oxygen supply.
- More complex series of reactions.
- Cannot resynthesise ATP at the start of exercise due to initial delay of oxygen from the cardiovascular system.
- Limited energy for ATP during high-intensity, short-duration work.
Define the energy continuum.
Represents how the energy systems interact to provide energy for the resynthesis of ATP.
Define threshold.
The point at which a particular energy system can no longer provide energy for working muscles.
What is the aerobic systems threshold determined by?
The threshold for the aerobic system will be determined by the intensity of the activity.
If it increases beyond a certain level then the performer will have to switch to anaerobic processes.
What are the ATP/PC and LA system thresholds determined by?
Anaerobically, the threshold is determined by the duration of the activity.
If we work at a high intensity for longer than 3 minutes we will have to switch to the aerobic system.
This point cane measured by the amount of lactic acid build up in the blood.
What does OBLA stand for?
Onset of Blood Lactate Accumulation
What is OBLA?
The point at which the concentration of lactic acid in the blood increases rapidly (mmol).
State 6 factors that affect which energy system is used.
- Intensity and duration
- Energy system threshold
- Oxygen availability
- Fuel availability
- Enzyme activation levels
- Fitness level
How do intensity and duration affect which energy system is used?
- High intensity, short duration - anaerobic = ATP/PC and LA
- Low intensity, long duration - aerobic (predominantly)
How does energy system threshold affect which energy system is used?
- 10 seconds - ATP/PC - 100m sprint
- 10-90 seconds - ATP/PC, LA - 200m
- 90 secs-3 minutes - LA, aerobic - 800m
- 3 minutes + - aerobic - marathon
How does oxygen availability affect which energy system is used?
If oxygen supply falls below that demanded for the exercise then the aerobic system threshold is met and the LA system will begin to breakdown glucose anaerobically to resynthesise ATP.
High intensity, short duration - break down glycogen
Low intensity, long duration - break down FFAs and glycogen
How does fuel availability affect which energy system is used?
- Fuel = PC - ATP/PC (high intensity, short duration) - limited store
- Fuel = glycogen - readily available in muscles, requires less oxygen so easier to break down than FFAs and is used for the first 20 minutes of exercise - once OBLA is reached the body has insufficient oxygen available so is available to burn FFAS.
- Fuel = FFAs - 20-45 minutes, requires 15% more oxygen to break down compared to glycogen.
How does enzyme activation levels affect which energy system is used?
- Enzymes = catalysts that activate the reactions that help breakdown PC, glycogen/glucose and FFAs to provide energy to resynthesise ATP.
- No enzymes = no reaction = no energy for resynthesis.
How does fitness level affect which energy system is used?
- Increased aerobic fitness = the more efficient respiratory and cardiovascular system are to take in, transport and use oxygen to break down glycogen and FFAs aerobically to resynthesise ATP.
What is O2 deficit?
The shortfall in oxygen at the beginning of exercise.
What is EPOC?
Excess Post-exercise Oxygen Consumption:
The amount of oxygen consumption, during recovery, required to restore the body back to its pre-exercise state.
What is VO2 max?
The maximum oxygen consumption attainable during maximal work.
What is ‘steady state’?
Vo2 consumption = energy requirements of exercise.
What are the 2 recovery processes?
Alactacid
Lactacid
Outline the Alactacid stage.
- Rapid
- Restores phosphogen stores
- Replenishes ATP and PC
- Replenishes myoglobin and haemoglobin with oxygen
- Requires 3-4 litres of oxygen, lasts 3 minutes
- 50% restored in 30 seconds
Outline the lactacid stage.
- Slow
- Removal/conversion of LA through:
- glucose, glycogen, protein
- pyruvic acid which then enters the Kreb’s cycle
- Requires 5-8 litres of oxygen
- Takes 1-24 hours depending on intensity
State 5 implications for training sessions.
- Consider the work/rest ratio during interval training - more effective than continuous as can train for longer distance with lower VO2 max and lower blood lactate level.
- Always do a warm up - reduces O2 deficit.
- Active cool down to speed up LA removal.
- Use of breaks to aid recovery.
- Mixture of anaerobic and aerobic will delay thresholds.