Energy systems Flashcards
how long does each energy system last for?
- ATP - 2-3secs
- ATP-PC - 5-8secs
- ANAEROIC GLYCOLYTIC - 40secs high intensity , 2-3mins low
- AEROBIC - 3+mins
ATP - adenosine triphosphate
- consists of 1 molecule of adenosine and 3 (tri) phosphate
- energy is realsed by breaking down the bonds
- only usable form of chemical energy
- provides enough energy for 2-3 secs
- ATPase (enzyme) splits the last phosphate - realises energy
ATP-PC
- works anaerobically
- uses phosocreatine - breakes down sacroplasm
- starts when the creatine kinase (enzyme) detects high levels of adenosine diphosphate
- breaks down the phosphocreatine into phosphate and creatine
- coupled reacting in sarcoplasm
- for every molecule of prophasecreatine broken down - enough energy to create one molecule of adenoisne triphosphate
- doesnt produce fatiging byproducts
- delays onset of anaerobic glycolytic system
sporting examples of ATP-PC system
- tumbling in gymnastics
- 60m sprint
- high jump
advantages of ATP-PC
- re-synthesized rapidly
- powerful movementns - doesnt require oxygen
- no fatiguing products produced
- phosphocreatine stores can be replenished quickly - 50% in 30, 100% in 2-3 minds
- can extend time using creatine supplements
disadvantages of ATP-PC system
- most inefficent energy system
- limited duration due to mimited supply of phosphocreatine
- one molecule of ATP can be re-synthesised for every molecule of phosphocreatine
- phosphocreatine resynthesized can only take place in presence of oxygen
anaerobic glycolytic system
- atp is resynthezied using glucose
- gluscose - supploed from digestions of carbs and stored as glycogen
- provides energy for high intensity activity
- lenght of the system depends on the fitness of athletes and intensity
- elite athletes could work for 45s
- reduce intensty it can last for 2-3mins
how the anaerobic glycolytic system works
- when the pc stores are low , glycogen phosphoralase is activated - breaks down glycogen into glucose - takes place in sarcoplasm
- further broken down into pyruvic acid - phosphofructokinase
- pyruvic acid breaks down into lactatic acid - lactate dehyrogenase
- energy is realised which allows ATP to be resynthesied
- two mocules of ATP are produced for one molecule of glucose broken down
main limitation of anaerobic glycolytic system
- onset of blood lactate accumulations (OBLA)
- decreases the pH (high acidity) within the muscle cells
- inhibts the enzyme and inhibits the breakdown of glucose and induces muscle fatigue
- exta oxygen is taken in to change lactic acid back into pyruvic acid - oxygen debt
effects of training the anaerobic glycolytic system
- increases the bodys tolerance to lactic acid and its buffering capcity against high levels of lactic acid
- more glycogen can be stored
- delays obla
- delays fatigue threshold
- devolps body adaptation to requirment - working at higher intensity
- the anaerobic glycolytic system threshold can be delayed
advantages of the anaerobic glycolytic system
- ATP can be resynthesized rapidly due to fewer chemical reactions
- used for very powerful movements
- glucose is readily foind in the muscle cells
- used in higher intensity, short duration activities - lasts longer than ATP-PC
- in presence of oxygen, lactic acid can be converted back into glycogen or used as fuel through oxidation into carbon dioxide and water
disadvantages of the anaerobic glycolytic system
- lactic acid produced as a by product
- limited duration due to build ip of lactate acid
- the accumillation of acid in the body denatures enzymes
- only 2 molecules of ATP can be resynthezied (5% as opposed to 95% under aerobic conditions)
the aerobic system
- intensity of the exercisr is low and oxygen is readily available
- presence of oxygen
- breaks fown glucose into carbon dioxide and water to provide energy
- the complete oxidation of glucose can produce up to 38 molecules of ATP
- also breaks down fatty acids, aminoc acids and glycogen to resynthesis ATP
stages of the aerobic system
- anaerobic glycolysis
- krebs cycle
- electron transport chain
stage 1 - anaerobic glycolysis
aerobic system
- no oxygen present
- works anaerobically in sarcoplasm
- glycolysis is the breakdown of glucose into pyruvic acid
- 2 molecules of ATP formed
- before pyruvic acid can move into the next stage, it splits into two acetyl groups
- carried into the krebs cycle by coenzyme A
stage 2 - krebs cycle
aerobic system
- acetyl coenzyme A diffuses into the matrix of mitrochondria
- acetyl coenzyme A combines with oxaloacetic acid, forming citric acid
- hydrogen is removed from citric acid and the rearranged form of citric acid undergos oxidative carboxylations
- carbon dioxide is transported from the lungs and breathed out
- hydrogen is taken to the electron transport chain
- 2 ATP molecules are produced
fats during the kreb cycle
aerobic system
- stored fat is broken down into glycerol and free fatty acids
- fatty acids undergo beta oxidation where they are converted into acetyl coenzyme A - then go through same process
- more ATP can be produced using fats - but takes 20% more oxygen
- long furation, low intensity and the predominant energy source
- produces 38 ATP insteaf of 36
stage 3 - electron transport chain
aerobic system
- hydrogen is transported through the chain
- occurs in the cristae of mitrochondria
- the hydrogen splits into hydrogen ions and electrons and are charged with potential energy
- hydrogen ions are oxidised to form water
- hydrogen electrons provide energy to resynthesis ATP
- 32-34 ATP molecules are formed (36-38ATP if there are fats)
advantages of the aerobic system
- large amounts of ATP products from 1 molecule of glycogen/fats
- activity can continue for hours
- large amounts of glycogen and fat within the body
- no harmful by products produced
disadvantages of the aerobic system
- require oxygen
- relatively slow production of energy
- can only produce energy for activites that are relativly low intensity
- 15-20% more oxygen is required if fats are being utilsed (even less intensity)
the energy continuum
the energy continuum
- describes the type of respiration ised by physical activty
- depedns on duration and intensity - will deterimine if its used to aerobic or anaerobic
- the energy systems do not work independently
ATP examples
the energy continuum
- football free kick
ATP-PC examples
the energy continuum
- tackle in hockey
- scrum in rugny
- badminton
anaerobic glycolytic examples
the energy continuum
- 100m swim
- horse riding
- pommel in gymnastics
aerobic examples
the energy continuum
- 2000m rowing
- golf putt
- cycling
factors that determine the predominant energy system used
- levels of fitness
- availability of oxygen
- availability of food fuels
levels of fitness
factors that determine the predominant energy system used
- greater aerobic fitness will mean you can perform at higher percentage of their VO2 max
- poor levels causes a person to reach OBLA
- OBLA prevents lactic acid removal
- as long as the removal of lactic acid keeps up with lactic acid production OBLA wont happen
availability of oxygen
factors that determine the predominant energy system used
- a performer with a high VO2 max will be able to sustain aerobic exercise and delay OBLA
- high VO2 max will typically have developed good respiratory and cardivascular system
- take in greater oxygen than those with a lower VO2 max
availability of food fuels
factors that determine the predominant energy system used
- glycogen becomes the major good fuel for first 20 mins
- fats then take over after 20 mins
- endurance athletes only exercise for as long as their glycogen store lasts for (~90mins)
- can only use fat as fuel when its used in conjuction with glycogen
- due to low solubility in the blood and more oxygen needed to break it down (15%)
- athletes will use glycogen loading - maximise their glycogen stores
differences in ATP generation between fast and slow twitch fibres
the energy continuum
- slow twitch fibres are used for low to medium intenstity (aerobic)
- fast twitch fibres are recruited for high intensties (anaerobic)
energy transfer during long duration/low intensity exercise
the energy continuum
- aerobic system
- demands of oxygen can be met
- steady state exercise
- glucose broken down more efficently
oxygen consumption during exercise
- oxygen consumption - the amount of oxygen we use to produce ATP
- also VO2 - at rest 0.3-0.4L
- start of exercise more O2 is used to provide more ATP - oxygen consumption increases
- intensity increases so does oxygen until they reach maximal oxygen consumption
VO2 max
oxygen consumption during exercise
- is the maxium amount of oxygen that can be taken in and utilised by the muscles of the body per min
- 3-6L
oxygen consumption during sub-maximal exercise
- happens when we start to exercise
- happens because it takes time for the circulatory system to respond to the increase of demand of oxygen
- takes time for mitrochondria to adjust to which the rate of aerobic respiration
- energy is intially provided anaerobically until the circulatory system and mitrochondria can cope
oxygen consumption during maximal exercise
- maximal oxygen deficit occurs
factors effecting VO2 max-aerobic power
- gender
- lifestyle
- difference in age
- body compostition
- training
- genetics
- physiological
gender
factors effecting VO2 max-aerobic power
- men approximatly have 20% higher VO2 max
- male 44-55ml/kg/min
- female 35-44ml/kg/min
lifestyle - decrease
factors effecting VO2 max-aerobic power
- smoking
- sedentary lifestyle
- poor diet
- poor fitness
difference in age
factors effecting VO2 max-aerobic power
- VO2 max declines with age as our bodies become less efficent
body composition
factors effecting VO2 max-aerobic power
- high % of body fat decreases VO2 max
training
factors effecting VO2 max-aerobic power
- VO2 max can be improved by up to 10-20% following a period of aerobic training
- continous , fartlek and aerobic interval
genetics
factors effecting VO2 max-aerobic power
- inherited factors of physiology limit possible improvements
physiological
factors effecting VO2 max-aerobic power
- increased maximal cardiac output
- increased stroke volume/hypertrophy/ejection
- greater HR
- increased haemoglobin
- increased glycogen
- increased myoglobin
- increased capilaries
- increased surface area of alveoli
- increased lacate tolerance
LOOK AT DIAGRAMS FOR ENERGY CONTINUMM
energy transfer during short duration/high intensity exercise
- energy needs to be provided rapidly
- reliant on ATP-PC and anaerobic glycolytic system
lactate accumulation
energy transfer during short duration/high intensity exercise
- high intensity , higher the lactic acid produced
- lactic acid breaks dowm quickly - realsing hydrogen ions
- the rest then combines with sodium ions or potassium ions
- forms salt lactate
- more lacate the more hydrogen ions which increase acidity
- slows down the enzyme and affects break down of glycogen - muscle fatigue
lactate threshold
energy transfer during short duration/high intensity exercise
- body moves from wokring aerobically to anerobically
- crossing the threshold is called lacate threshold
- at rest appromximatly 1-2 millimoles per litre of lactate can be found in blood
- expressed VO2 max - as fitness increases lactate threshold can be delayed
OBLA
energy transfer during short duration/high intensity exercise
- levels of lacate rise dramtically OBLA occurs
- occurs when the concentration of lactae is around 4 millimoles per litre of blood
VO2 max
energy transfer during short duration/high intensity exercise
- average athletes - 50-60% of their VO2 max
- elite athletes - 70-90%
- training has milimted affect on it as its largely genetically determined
factors affecting the rate of lactate accumlation
- exercise intensity
- muscle fibre type
- fitness of perfomer
- rate of blood lactae removal
- repsiratory exchange ratio
exercise intensity
factors affecting the rate of lactate accumlation
- higher the intensity , higher the demand for ATP
- faster OBLA occurs due to lactic acid being formed as a result of anaerobic glycolysis
muscle fibre type
factors affecting the rate of lactate accumlation
- slow twitch fibres produce less lactate than fast twitch fibres
- in the presence of oxygen, glycogen can be broken down effectivly with little lacate production
fitness of performer
factors affecting the rate of lactate accumlation
- a person who trains regulary is more likely to delay OBLA
- adaption occur to trained muscles
- increased mitrochondria and myoglobin and increased capillarisation improve capcity of aerobic respiration
- avoids working anaerobically
rate of blood lactate removal
factors affecting the rate of lactate accumlation
- if the rate of lactate removal is lower than the rate of lactae production
- lacate will start to accumaltae in blood until OBLA is reacher
respiratiory exchange ratio
factors affecting the rate of lactate accumlation
- is the ratio CO2 produced compared to O2 consumed
- is more CO2 produced anaerbic respiration occurs
- causing glycogen to be prefered energy fuel and consequently there is a greater change of accumulation of lacate
lactate-producing capcity and sprint/power performance
- elite athletes will have a better anaerobic endurance - their body has adpated to cope with high levels of lactate
- buffering - a process that will increase the rate of lactae removal and have lower lacate levels
- “sponge soaking up lactate”
- trained muscles have greater number of mitrochindria and the associate oxidative enzymes , increased capillarisation density and more myoglobin
why we measure energy expenditure
- gives an indication of the intensity of the exercise
- identifies levels of fitness
- hughlight dietry requirements needed for the performer to recovery and replace the energy they have used
- provide feedback on the effectiveness of a training program
measurements of energy expenditure
- indirect calorimetry
- lactate sampling
- VO2 max test
- respiratory exchange ratio
indirect calorimetry
measurements of energy expenditure
- accurate estimate of energy expenditure through gas exchange
- measures how much CO2 produces and O2 consumed
- at both rest and aerobic exercise
- measures then turnt into a heat equivalent
- determines calorific needs
- finds out the main substrate used (fats or carbs)
- very reliable
lactate sampling
measurements of energy expenditure
- accurate and objective
- measures levels of lacate in blood
- tiny blood sample and anyaslised on handheld device
- also measures exercise intensity - higher intensity at which lacate threshold occurs - fitter athlete
- slecets relavnt training zones
- regular testing allows coaches to see wether imprvements have occured
- if they have lower lactate level at same intensity - they have improved
VO2 max test
measurements of energy expenditure
- multi stage fitness test
- compared to a standards result table
- prediction or indication of a performers VO2 mx
- specialist equiments in a laboratiry - direct gas anaylsis
- direct gas analysis - in which the conentration of oxygen that is inspired and the concentration of carbon dioxide that is expired is measured
respiratory exchange ratio
measurements of energy expenditure
- ratio of carbon dioxide produced compared to oxygen consumed
- infomation and fuel usage during exercise
- carbs , fats , proetins can all be oxidsided to produce energy
- calculating RER will deterimes wich energy source is being oxisded - wether the performer is working aerobically or anaerobically
- attach gas analyis while on treatmill
RER equation and values
- CARBON DIOXIDE EXPIRED PER MIN/OXYGEN CONSUMED PER MIN
- RER val close to 0.7 = fats
- RER cal close to 1 = carbs
- RER val over 1 = anaerbically
specialist training methods
- altidude training
- HIIT training
- plyometric training
- SAQ
altidude training
impact of specialist training methods on energy system
- aerobic training method
- endurance athletes
- training for minimum of 30 days
- 2500+ sea level
- lasts for 4-6 weeks
- 3 phases - acclimatisation , primary training , recovery
- increased red blood cells , EPO increase
- increased myoglobin so more oxygen is stored
positives of altitude training
impact of specialist training methods on energy system
- increases aerobic power and VO2 max
- perform at higher intensities for longer without anaerobic
- increased tolerance to lactate
- increased cardiovasular endurance
negatives of altitude training
impact of specialist training methods on energy system
- altitude sickness
- loose fitness
- effect mental health - away from home
- loose effect quickly
- expensive
- time consuming
HIIT training
impact of specialist training methods on energy system
- anaerobic training method
- high intensty interval training
- periods of high intensity follwed by rest
- 20-60mins/6-8 cycles
- games players
- ATP-PC and anaerobic glycolytic system used in high intensity
- 80-90% max hr - high intensity
- 40-50% max hr - low intesnity
postives of HIIT training
impact of specialist training methods on energy system
- anaerobic power - fast sprints
- develops cardiovascular system during recovery periods of games
- made sport specific
- improved range of compoundents of fitness
- done individually or a team
negatives of HIIT training
impact of specialist training methods on energy system
- muscle sorness
- lead to injury - stress on joints
- hard to work out ratios of work and rest
- cant develop tactics
- not suitable for all players
plyometric training
impact of specialist training methods on energy system
- anaerobic training method
- high explosive exercise
- power and explosive strenght
- developd fats twitch 2x fibres
- muscle spindles involved - detect over stretch
- eccentric to concentric muscle movements
- 3 stages - pre-stretch , amortisation , muscle contraction
positives of plyometric training
impact of specialist training methods on energy system
- increased size of fast twitch fibres
- increase speed of contraction
- reduce injury in sporr
negatives of plyometric training
impact of specialist training methods on energy system
- high risk of injury
- thorough warm up - longer
- other compnents of fitness may be better than other
SAQ
impact of specialist training methods on energy system
- anaerobic training
- speed , agility , quickness
- multidimensional movement, speed, dymanic balance and explosive strentgh
- progression exercise to improve motor abilities to do skills faster
- zigzag runs, poles , hurdles , parachutes
- type 2x fast twitch fibres
postives of SAQ training
impact of specialist training methods on energy system
- improved agility
- speed
- reaction time
- motor skill
- spatial awarness
negatives of SAQ training
impact of specialist training methods on energy system
- can loose tenchique as skill are carried out quickly
- requires equipment
- not good for long distance
- plyometrics may be more effective
oxygen consumption during recovery
- EPOC - excess post exercise oxygen consumption
- when a performer finishes exercise oxygen consumption remains high
- two compondents of EPOC - fast replishment (alactacid compondent) , slow replenishment (lactacid compondent)
fast replenishment stage
- uses the extra oxygen that is taken in during recovery to restore ATP and phosphocreatine and re-sature myoglobin with oxygen
- complete resoration of phosocreatine takes up to 3 mins - 50% in 30secs
- myoglobin has a high affinity for oxygen
- stores oxygen in the sarcoplasm that has diffused haemoglobin
- takes 2 mins and uses 0.5L of oxygen
slow replenishment stage
oxygen consumption during recovery
- uses oxygen take in during recovery to perform several funtions
- removal of lactic acid
- maintance of breathing and heart rate
- glycogen replenishment
- increase body temperature
removal of lactic acid
oxygen consumption during recovery - slow replenishment
- occurs has soon as lactic acid appears in the muscle cells
- takes up 5-6L of oxygen in half an hour of recovery - removes 50% of lactic acid
- majority of lactic acid can be oxidesed in mitrochondria - a cool down allows the muscles to keep high metabloic rate and capillaries dilated - allows oxygen to flush out lactic acid
- can also be removed by;
- oxidation into CO2 and water in the inactive muscles
- transported in the blood to the liver coverted to glucose - cori cycle
- coverted to protein
- removed in sweat and urine
maintenance of breathing and heart rate
oxygen consumption during recovery - slow replenishment
- allows extra oxygen to provide energy needed for the respiratory and heart muscles
- assits recovery as extra oxygen is used to replenish ATP and phoshocreatine
- restauants myoglobin and removes lactic acid
glycogen replenishment
oxygen consumption during recovery - slow replenishment
- depends on type of exercise and how many carbs are consumed after
- significant amount of glycogen can be restored in less than 30 mins following high intensoty and short duration - cori cycle
- can accelerate by eating high carb meals within an hour of exercising
- 30 mins after - carbs and protein in a 3:1 or 4:1
- 1-3 hours after - a meal high in carbs and healthy fats
increase body temperature
oxygen consumption during recovery - slow replenishment
- when temp is high, repsiratory rate stays high
- extra oxygen is needed to fuel the increase temperature
