AS Applied Anatomy and Physiology Flashcards
What is the function of the blood transport system?
To deliver blood around the body to get oxygen to respiring tissues
How is blood transported around the body?
In blood vessels
What are the roles of the blood?
- deliver oxygen to working muscles
- remove waste products
- transport nutrients, glucose and hormones
- thermoregulation
- protect body from infection
- clots to prevent blood loss
What are the 2 parts to the double circulatory system?
Systemic and pulmonary
What is the systemic circulatory system?
Pump blood from heart to body and back via the aorta and vena cave
What is the pulmonary circulatory system?
Pump blood from the heart to lungs and back via the pulmonary artery and vein
What is the role of the septum?
Split the heart into left and right
Where is the SA node found?
Right atrium
Which ventricle has the thickest walls and why?
- left ventricle
- has the highest pressure
What are the semi lunar valves?
- found between the ventricles and the arteries
- prevent the back flow of blood
What is the cardiac conduction system?
- SA node emits an electrical impulse
- impulse spreads throughout the atria causing them to contract
- impulse arrives at AV node
- AV node delays transmission for 0.1s allowing atria to contract
- impulse sent down septum via bundle of His
- purkinje fibres spread impulse throughout muscular walls
- ventricles contract
What does myogenic mean?
Generates its own impulse/self regulating e.g. the heart
Where is the neural control mechanism located?
In the medulla oblongata
Are the neural control mechanisms voluntary or involuntary?
Involuntary
What is the role of the sympathetic nervous system?
Sends out impulses to SA node to increase heart rate before and during exercise
What is the role of the parasympathetic nervous system?
Sends impulses to SA node to decrease heart rate after exercise
What is the role of receptors?
Detect changes in the body
What is the role of chemoreceptors?
- detect changes in blood acidity
- during exercise there is an increase in blood acidity so the sympathetic NS is stimulated causing heart rate to increase
What is the role of baroreceptors?
- detect blood pressure changes
- changes in pressure sends signals to medulla oblongata
- stretch at high arterial pressure to allow heart rate to decrease
What is the role of proprioceptors?
- detect changes in muscle movement
- located in muscles, tendons and joints and medulla oblongata
- detects movement at start of exercise and sends impulse to medulla oblongata to stimulate sympathetic NS
What is anticipatory rise?
Increase of heart rate before exercise (mimics the sympathetic NS)
What hormone causes anticipatory rise?
Adrenaline
What is stroke volume and what happens during exercise?
- volume of blood leaving the left ventricle per beat
- increases during exercise
- 70ml per beat
What is venous return and what happens to it during exercise?
- volume of blood returning to the heart via veins
- increases during exercise
- directly proportional to stroke volume
What is ejection fraction?
- percentage of blood pumped out of the left ventricle per beat
- average is 60%
What is the elasticity of cardiac fibres?
The degree of stretch of cardiac tissue during the diastole phase of the cardiac cycle
What is Starlings Law?
The more the cardiac fibres stretch the greater the force of contraction which increases ejection fraction
What is bradycardia?
A decrease in resting heart rate
What is CHD?
- coronary heart disease
- coronary arteries became blocked up due to fatty deposits
- atherosclerosis
- fatty deposits are called atheroma
What is high blood pressure and how can it be reduced?
- a high force exerted by the blood against the blood vessel walls
- can be reduced by aerobic exercise
What are LDLs?
- low density lipoproteins
- bad cholesterol
- transported in blood to the tissues
What are HDL?
- high density lipoproteins
- good cholesterol
- transport excess cholesterol in the blood to the liver where is it broken down
What is a stroke?
- occurs when the blood supply to the brain is cut off causing damage to brain cells
- aerobic exercise can reduce risk of stroke by 27%
What is cardiovascular drift?
As heart rate increases, over time stroke volume decreases
What are the causes of cardiovascular drift?
- reduction in fluid in blood due to vasodilation
- reduces venous return and stroke volume
- increase in cardiac output due to thermoregulation
What is the structure and function of arteries?
- thick walls
- made of elastic and muscle fibres
- can vasoconstrict and vasodilate
- carry blood away from heart
- main one is aorta
What is the structure and function of arterioles?
- small arteries
- made of elastic and muscle fibres
- vasodilate and vasoconstrict
What is the structure and function of capillaries?
- tiny blood vessels supplying nutrients to cells and removing waste products
- 1 cell thick
- around lungs and muscles
What is the structure and function of veins?
- thin walls
- have valves
- carrying blood to the heart
What is the structure and function of venuoles?
- small veins
- have pocket valves
What is blood pressure?
Force exerted by blood against the blood vessels walls
How do you calculate blood pressure?
Blood flow x resistance
What is systolic pressure?
Pressure of contraction
What is diastolic pressure?
Pressure of relaxation of heart
What are the 4 venous return mechanisms?
- skeletal muscle pump
- pocket valves
- involuntary/smooth muscle in vein walls
- respiratory pump
What is the skeletal muscle pump?
Contracting muscles squeeze the walls of the veins to pump blood to the heart
What are pocket valves?
Prevent back flow of blood and ensures it is unidirectional
What is the function of smooth muscle in vein walls?
Contract when stimulated by sympathetic nervous system
What is the role of the respiratory pump?
Changes in pressure in the thorax during inspiration compressing the veins and squeezes blood towards the heart
How much oxygen combines with haemoglobin during exercise?
97%
How many oxygen molecules can a fully saturated haemoglobin molecule carry?
4
What stores oxygen in the muscles?
Myoglobin as it has a higher affinity to oxygen than haemoglobin
What is shown in the oxygen dissociation curve?
- at low partial pressures of oxygen, haemoglobin unloads its oxygen
- at high partial pressures of oxygen, haemoglobin loads its oxygen
What is the Bohr shift?
- due to more carbon dioxide in the blood there is a low pH
- curve shifts to the right
- haemoglobin unloads easier as there is a reduced affinity for oxygen
What factors cause the Bohr shift?
- increased blood temperature
- partial pressure of carbon dioxide increases
- a lower pH
What is vascular shunting?
Directing blood to skeletal muscles for respiration during exercise
How much blood is directed to the muscles at rest and during vigorous exercise?
At rest is 15-20% and during exercise is 80-85%
What is the importance of redistribution of blood?
- increased supply of oxygen to working muscles
- remove waste products
- ensure move blood to skin for thermoregulation
- direct more blood to heart as it is a muscle and requires extra oxygen during exercise
What is vasodilation?
Blood vessels around skeletal muscles widen to increase blood flow to muscles
What is vasoconstriction?
Blood vessels narrow around nonessential organs to decrease blood flow to muscles e.g. intestines
What is A-VO2 difference?
- arterio-venous difference
- the difference between the oxygen content of arterial blood arriving at the muscles and the venous blood leaving the muscles
Why is A-VO2 difference low at rest?
Not much oxygen is required by the muscles
Why is A-VO2 difference high during exercise?
- more oxygen is needed from blood for the muscles to respire
- this will cause an increase in gas exchange at alveoli
What does regular aerobic training do to A-VO2 difference?
- increases it
- trained individuals can extract a greater amount of oxygen from the blood
What are the alveoli and the adaptations?
- responsible for gas exchange between the lungs and blood via diffusion
- thin walls (1 cell thick), short diffusion pathway
- extensive capillary network, excellent blood supply
- lots of alveoli that are highly folded, large surface area
How do the mechanics of breathing work?
- air moves from high to low pressure down a pressure gradient
- the steeper the gradient the faster the air flows
How does inspiration work?
- external intercostal muscles contract
- ribs pulled up and out
- diaphragm contracts and flattens
- volume of thorax increases
- pressure decreases compared to atmosphere so air moves in down its pressure gradient
How does expiration work?
- internal intercostal muscles contract
- ribs move down and in
- diaphragm relaxes and domes up
- volume of thorax decreases
- pressure increases compared to the air so air moves out down its pressure gradient
What is tidal volume and what happens during exercise?
Volume of air inspired/expired per breath, 0.5L at rest and increases during exercise
What is minute ventilation and what happens during exercise?
The volume of air inspired/expired per minute (breathing rate x tidal volume) and increases during exercise
What is inspiratory reserve volume and what happens during exercise?
The extra volume of air you can inspire which decreases during exercise as tidal volume increases
What is expiratory reserve volume and what happens during exercise?
The extra volume of air you can expire which decreases during exercise as tidal volume increases
What is residual volume and what happens during exercise?
The volume of air left in the lungs after breathing which remains the same during exercise
What does a spirometer measure?
Measures the volume of air inspired/expired
What is partial pressure?
The pressure a gas exerts in a mixture of gases (mmHg)
How does gas exchange work at the lungs?
- higher partial pressure of oxygen in the alveoli so oxygen moves down concentration gradient from alveoli to blood
- higher partial pressure of carbon dioxide in the lungs so carbon dioxide moves down concentration gradient from blood to alveoli
How does gas exchange work at the muscles?
- higher partial pressure of oxygen in the blood so oxygen moves down concentration gradient from blood to muscles
- higher partial pressure of carbon dioxide in the muscles so carbon dioxide moves down its concentration gradient from muscles to blood
What is the effect of exercise on the diffusion gradient?
- muscles use more oxygen
- steeper diffusion gradient
- more oxygen diffuses into blood and into muscles
How do we regulate pulmonary ventilation during exercise?
- neural control (brain and nervous systems)
- chemical control (blood acidity)
- hormonal control
What is the role of the sympathetic and parasympathetic nervous system in regulation of pulmonary ventilations?
- the sympathetic system increases breathing rate before and during exercise
- the parasympathetic system decreases breathing rate after exercise
What is the respiratory centre?
- located in the medulla oblongata
- controls rate and depth of breathing using neural and chemical control
How do we control breathing during exercise?
- increased carbon dioxide in blood stimulates the respiratory centre to increase breathing rate
- the inspiratory centre sends out impulse in phrenic nerve to inspiratory muscles causing them to contract
- can also be stimulated by blood acidity
What is the inspiratory centre?
Responsible for inspiration and expiration
What is the expiratory centre?
Stimulates expiratory muscles during exercise
What are factors that control breathing?
Mechanical factors, baroreceptors and stretch receptors
What are mechanical factors that control breathing?
Proprioceptors that are located in joints and muscles and provide feedback to RC to increase breathing
What are baroreceptors in the control of breathing?
Decrease in blood pressure detected in aorta and carotid results in increased breathing rate
What are stretch receptors in the control of breathing?
Prevent over inflation of lungs by sending impulses to the expiratory centre
How does adrenaline regulate breathing?
Before exercise the brain sends an impulse to adrenal glands which secretes adrenaline into the blood to increase breathing rate in preparation for exercise
How does minute ventilation during sub maximal exercise change?
- anticipatory rise as a result of adrenaline
- rapid rise due to an increase in acidity and an increase in temperature and muscle movement (medulla oblongata increase BR an TV)
- levels off as a plateau is met
- rapid decline as exercise stops
- slower decrease due to need for oxygen to get rid of lactic acid
What are the effects of training on respiration?
- small increase in lung volumes and capacities
- increased number of red blood cells (haemoglobin)
- increase in capillary density
- increased number of mitochondria
- energy demands met at lower minute ventilation
- faster recovery post exercise
How does smoking affect the respiratory system?
- irritates the trachea and bronchi (cilia)
- reduced lung functions
- damage cilia and alveoli
- reduced efficiency of gas exchange leading to an increase risk of COPD
- oxygen transport declines as CO combines with haemoglobin more readily than oxygen a it has a higher affinity
What is the autonomic nervous system?
Regulates the function of internal organs e.g. heart and some skeletal muscles, and is involuntary
What response does the sympathetic NS elicit?
Fight or flight
What response does the parasympathetic NS elicit?
Rest and relax
What determines your proportion of muscle fibres
Genetics
What are slow twitch muscle fibres?
- type 1
- aerobic exercise
- e.g. marathon
What are fast twitch muscle fibres?
- type 2a and 2x
- anaerobic
- example of type 2a is 400-800m
- example of type 2x is 100m
What are the functional characteristics of type I muscle fibres?
- slow contraction speed
- low force produced
- high resistance to fatigue
What are the structural characteristics of type I muscle fibres?
- small motor neurone size
- high mitochondrial density
- high capillary density
What are the functional characteristics of type IIa muscle fibres?
- fast contraction speed
- high force produced
- moderate resistance to fatigue
What are the structural characteristics of type IIa muscle fibres?
- large motor neurone size
- moderate mitochondrial density
- moderate capillary density
What are the functional characteristics of type IIx muscle fibres?
- very fast contraction speed
- very high force produced
- very low resistance to fatigue
What are the structural characteristics of type IIx muscle fibres?
- very large motor neurone
- very low mitochondrial density
- vey low capillary density
What is a motor unit?
- a motor neurone and its muscle fibres
- there is only one type of muscle fibre in a unit
What do motor neurone branches end in?
Neuromuscular junctions
What is the difference between small and large motor units
- small motor units are used for fine motor control (e.g. eye movement)
- large motor units are used to gross motor control (e.g. quadricep movement)
What is the all or nothing law?
Once a motor neurone stimulates muscle fibres, all fibres contract or no fibres contract
What must be crossed for a motor unit to contract?
The threshold
What is wave summation?
The greater the frequency if stimuli the greater the tension so the greater the force of contraction
What is a tetanic contraction?
The greater the frequency of stimuli the less time for rest so there is a build up of calcium so there is a high force, smooth, sustained contraction
What is spatial summation?
When impulses are received at multiple places on the motor unit and add up causing a high force contraction
What does PNF mean?
Proprioceptive neuromuscular facilitation
What is PNF stretching?
- passive stretch
- effective way to increase flexibility and range of motion
- as antagonist relaxes to allow agonist to contract and lengthen
- proprioceptors detect a change in muscle length to prevent injury
What are examples of proprioceptors?
Muscle spindles and golgi tendons
Where do muscle spindles lie?
Between skeletal muscle fibres
What is the role of muscle spindles?
Detect how far/fast a muscle is stretched and sends impulse to CNS to cause muscle to contract preventing over stretching and injury
Where are golgi tendon organs found?
Between muscle fibre and tendon
What is the role of golgi tendon organs?
- detect levels of tension in muscle
- as muscle contracts isometrically in PNF they sense increase in tension and send inhibitory signals to brain allow antagonist to relax and lengthen
What is autogenic inhibition?
A sudden relaxation of muscle in response to high tension
What are the three types of joints?
- fibrous/fixed joints e.g. cranium
- cartilaginous/slightly moveable e.g. pivot joint at neck
- synovial/freely moveable joint e.g. ball and socket at shoulder
What are the articulating bones at the ankle?
Talus, tibia and fibula
What are the articulating bones at the knee?
Femur and tibia
What are the articulating bones at the elbow?
Humerus, radius and ulna
What are the articulating bones at the shoulder?
Humerus and scapula
What are the articulating bones at the hip?
Femur and pelvis
What are ball and socket joints?
Allow movement in every direction e.g. shoulder or hip
What are hinges joints?
Allows movement in one direction (flexion/extension) e.g. elbow or hip
Where is the sagittal plane?
Splits the body into left and right
What is a sporting example at the sagittal plane?
Running e.g. 100m sprint
Where is the frontal plane?
Splits the body into front and back
What is a sporting example at the frontal plane?
Cartwheel/ star jumps
Where is the transverse plane?
Splits the body into top and bottom
What is a sporting example at the transverse plane?
Golf swing
Where is the transverse axis?
Through the sides of the body
What is a sporting example on the transverse axis?
Somersault
Where is the sagittal axis?
Through the belly button
What is a sporting example on the sagittal axis?
Cartwheel
Where is the longitudinal axis?
Through the top of your head
What is a sporting example on the longitudinal axis?
Pirouette
What movements are at the sagittal plane?
Flexion and extension
What movements are at the frontal plane?
Adduction and abduction
What movements are at the transverse plane?
Rotation
What movements are in the transverse axis?
Flexion and extension
What movements are at the sagittal axis?
Abduction and adduction
What movements are at the longitudinal axis?
Rotation
What axis pairs with the sagittal plane?
Transverse axis
What plane pairs with the transverse axis?
Sagittal plane
What movements happen at the sagittal plane and transverse axis?
- flexion/extension
- 100m sprint
What is plantar-flexion?
Planting the foot on the floor/pointing toes (agonist gastrocnemius)
What is dorsi-flexion?
Flexed feet while on floor/lifting toes up (agonist tibialis anterior)
What axis pairs with the frontal plane?
Sagittal axis
What plane pairs with the sagittal axis?
Frontal plane
What movement is at the frontal plane and sagittal axis?
- abduction/adduction
- cartwheel
What axis pairs with the transverse plane?
Longitudinal axis
What plane pairs with the longitudinal axis?
Transverse plane
What movement is at the transverse plane and longitudinal axis?
- horizontal abduction/adduction
- golf swing
What is meant by prime mover?
Agonist
What are the antagonistic muscle pairs?
- bicep and tricep
- quadricep and hamstring
- tibialis anterior and gastrocnemius
- gluteus maximus and illiopsoas
What happens in the upwards phase of a bicep curl?
- bicep contracts concentrically getting shorter fatter and harder
- bicep is agonist and tricep is antagonist (relaxes)
- angle between origin and insertion gets closer
What happens in the downwards phase of a bicep curl?
- the bicep contracts eccentrically getting longer and thinner under tension
- the bicep is the agonist and the tricep is the antagonist (relaxes)
- angle between origin and insertion gets bigger
What happens in the downwards phase of a press up?
- tricep contracts eccentrically getting longer and thinner
- tricep is the agonist and bicep is the antagonist (relaxes)
- angle between origin and insertion gets smaller
What happens in the upwards phase of a press up?
- tricep contracts concentrically getting shorter fatter and harder
- tricep is the agonist and bicep is the antagonist (relaxes)
- angle between origin and insertion gets bigger
What is the agonist and antagonist during elbow flexion?
- agonist = bicep
- antagonist = tricep
What is the agonist and antagonist during elbow extension?
- agonist = tricep
- antagonist = bicep
What is the agonist and antagonist during ankle plant-flexion?
- agonist = gastrocnemius
- antagonist = tibialis anterior
What is the agonist and antagonist during dorsi-flexion?
- agonist = tibialis anterior
- antagonist = gastrocnemius
What is the agonist and antagonist during knee flexion?
- agonist = hamstring
- antagonist = quadricep
What is the agonist and antagonist during knee extension?
- agonist = quadriceps
- antagonist = hamstrings
What is the agonist and antagonist during hip flexion?
- agonist = illiopsoas
- antagonist = gluteals
What is the agonist and antagonist during hip extension?
- agonist = gluteals
- antagonist = iliopsoas
What is the agonist and antagonist during hip adduction?
- agonist = adductors
- antagonist = gluteus
What is the agonist and antagonist during hip abduction?
- agonist = gluteus
- antagonist = adductors
What is the agonist and antagonist during horizontal hip adduction?
- agonist = adductors
- antagonist = gluteus
What is the agonist and antagonist during horizontal hip abduction?
- agonist = gluteus
- antagonist = adductors
What is the agonist and antagonist during shoulder flexion?
- agonist = anterior deltoid
- antagonist = latissimus dorsi
What is the agonist and antagonist during shoulder extension?
- agonist = latissimus dorsi
- antagonist = anterior deltoid
What is the agonist and antagonist during horizontal shoulder abduction?
- agonist = latissimus dorsi
- antagonist = pectorals
What is the agonist and antagonist during horizontal shoulder adduction?
- agonist = pectorals
- antagonist = latissimus dorsi
What is the agonist and antagonist during shoulder adduction?
- agonist = latissimus dorsi
- antagonist = deltoid
What is the agonist and antagonist during shoulder abduction?
- agonist = deltoid
- antagonist = latissimus dorsi
What is an isotonic concentric contraction?
- muscle moves and gets shorter, fatter and harder under tension
- e.g. upwards phase of bicep curl
What is isotonic eccentric concentration?
- muscle moves and gets longer and thinner under tension
- e.g. bicep in downwards phase of bicep curl
What is an isometric muscle contraction?
- muscle doesn’t move under tension
- e.g. crucifix
Where does energy for muscle contractions come from?
ATP
What enzyme breaks ATP into ADP?
ATPase
What is ATP?
Adenosine, ribose sugar and 3 inorganic phosphates
What is ADP?
Adenosine, ribose sugar and 2 inorganic phosphates
What reaction breaks ATP into ADP?
Hydrolysis reaction
What reaction forms ATP from ADP?
Condensation reaction
What are the 3 energy systems?
Aerobic, anaerobic glycolytic and ATP-PC
What are the characteristics of the aerobic system?
- low intensity
- high duration
- oxygen is present
- 38 ATP molecules are produced from one glucose molecule
What are the 3 stages of the aerobic system?
- Glycolysis
- Krebs Cycle
- Electron Transport Chain
What is glycolysis?
- in sarcoplasm of the muscle cell
- glucose is broken down into pyruvic acid creating energy to resynthesise 2 ATP
- pyruvic acid is oxidised into 2 acetyl groups
- carried into stage 2 by co enzyme A
What is the Krebs cycle?
- matrix of mitochondria
- acetyl groups combine with oxaloacetic acid to form citric acid
- hydrogen is removed and undergoes oxidative carboxylation removing carbon and hydrogen
- 2 ATP molecules are resynthesised and carbon dioxide is produced
- hydrogen goes to stage 3
What is the electron transport chain?
- in mitochondria cristae
- hydrogen splits into hydrogen ions and electrons
- electrons provide energy to resynthesise 34 ATP molecules
How many ATP molecules are made in the aerobic system?
38 ATP molecules
In what conditions are fats broken down?
Aerobic conditions (in the presence of oxygen)
What is beta oxidation?
- stored fats are broken into glycerol and 3 fatty acids
- fatty acids undergo beta oxidation into 2 acetyl groups
- follows the same route as glucose
Why is beta oxidation better than the use of glycogen for synthesising ATP?
More ATP is resynthesised from 1 fatty acid than 1 glycogen molecule
What are the advantages of the aerobic system?
- more ATP can be produced (38)
- no fatiguing by products
- lots of glycogen/fat stores so exercise can last for longer
What are the disadvantages of the aerobic system?
- complex system so takes a while to meet oxygen demand
- glycogen and fatty acids must be completely broken down
- fatty acids require lots of oxygen to be broken down
What are the characteristics of the ATP-PC system?
- 0-10s
- very high intensity
- use of phosphocreatine
- without oxygen
What is the process of the ATP-PC system?
- creatine kinase detects high levels of ADP
- breaks down phosphocreatine producing energy to resynthesise 1 ATP molecule
What does creatine kinase do?
Detects high ADP levels and breaks down phosphocreatine
What is the ratio of the aerobic system?
1:38
What is the ratio of the ATP-PC system?
1:1
What are the advantages of the ATP-PC system?
- ATP can be resynthesised rapidly
- phosphocreatine stores can be restored quickly (50% in 30s and 100% in 3mins)
- can extend time using ATP-PC system with creatine supplements
What are the disadvantages of the ATP-PC system?
- limited phosphocreatine supply
- only 1 ATP molecule synthesised
- phosphocreatine can only be restored in presence of oxygen
What are the characteristics of the anaerobic glycolytic system?
- carbohydrate burning system
- 400-800m
- 10s-3mins
- relatively high intensity
What are the processes in the anaerobic glycolytic system?
- in the sarcoplasm of the muscle
- glycogen phosphorylase breaks down glycogen into glucose
- phosphofructokinase breaks down glucose into pyruvic acid
- pyruvic acid os broken down into lactic acid by lactate dehydrogenase
- 2 molecules of ATP are resynthesised
What is the ratio of ATP produced in the anaerobic glycolytic system?
1:2
What is the role of glycogen phosphorylase?
To break glycogen into glucose
What is the role of phosphofructokinase?
To break glucose into pyruvic acid
What is the role of lactate dehydrogenase?
To break pyruvic acid into lactic acid
What are the advantages of the anaerobic glycolytic system?
- ATP can be resynthesised quickly
- in presence of oxygen lactic acid can be converted into glycogen and used as fuel
- can be used for sprint finish
What are the disadvantages of the anaerobic glycolytic system?
- OBLA occurs causing fatigue
- a relatively small amount of energy released
What is the energy continuum?
A term used to describe which energy system is most predominant in an activity and the contribution of the 3 systems
What are sporting examples of when the ATP-PC system is predominant?
100m sprint, javelin
What are sporting examples of when the anaerobic glycolytic system is predominant?
400m run, 200m swim or a gymnastics floor routine
What are sporting examples of when the aerobic system is predominant?
Marathon or a football match
What is a threshold?
Where one system is exhausted and the next one takes over
What is the ATP-PC threshold?
When the ATP-PC system is exhausted and anaerobic glycolytic system takes over
Ho would you spot thresholds on a graph?
Where the energy systems cross over
What energy system is associated with slow twitch muscle fibres?
The aerobic system so production of 38 ATP is slow but fibres are endurance based so less likely to fatigue
What energy system is associated with type 2x muscle fibres?
The ATP-PC/anaerobic glycolytic system so 1-2 ATP are made fast but doesn’t last long as fibres have a low resistance to fatigue
Why is the aerobic system predominant when intensity is low?
Demand for oxygen is easily met and glucose can be broken down more efficiently as oxygen is present
Why are fats only burnt at very low intensities?
Fats need lots of oxygen to be broken down so as intensity increases the oxygen demand increases which cannot be me so the break down of glycogen begins
What is oxygen consumption?
The amount of oxygen used to produce ATP, also known as VO2 and increases as intensity increases
What does is mean if you have a high maximal oxygen consumption?
The better the aerobic capacity
What is VO2 max?
The maximum volume of oxygen that can be taken up ad used by the muscles per minute
What is submaximal oxygen deficit?
At start of exercise you use the anaerobic system until the circulatory system and mitochondria can meet oxygen demand
What is MAOD?
Maximum oxygen deficit
Why is oxygen deficit bigger during maximal exercise?
Performer is short of oxygen at the start so they have to work more anaerobically
When does oxygen deficit occur?
At the start of exercise
Why does oxygen deficit occur?
Because performers work anaerobically at the start of exercise as they cannot meet the oxygen demand yet
When does oxygen debt occur?
After exercise
What is the other name for oxygen debt?
EPOC
What does EPOC stand for?
Excess post-exercise oxygen consumption
What is EPOC?
Extra oxygen consumed after exercise to aid recovery
What are the components to EPOC?
Fast and slow component
What is the fast component of EPOC?
Extra oxygen consumed to restore ATP and phosphocreatine and restaturate myoglobin with oxygen
What is myoglobin?
A protein that stores oxygen in the muscles and has a higher affinity to oxygen than haemoglobin
What is the slow component of EPOC?
Extra oxygen consumed after exercise to remove lactic acid
What are the ways that you can remove lactic acid?
- lactic acid can be converted into pyruvic acid which is oxidised into CO2 and water and used as an energy source
- can be transported to the liver where it is converted into glucose and glycogen and stored (cori cycle)
- can be converted into proteins (urea)
- can be lost in sweat and urine
Why does a high breathing and heart rate maintain after exercise?
Extra oxygen is needed to assist recovery to replenish ATP and CP stores, resaturate myoglobin and remove lactic acid helping total return body to a pre-exercise state
What process maintains increased body temperature after exercise
Vasoconstriction
Why is a high temperature maintained after exercise?
To ensure expiratory rates are high so lots of extra oxygen is consumed until the body returns to normal
How is lactate made?
Lactic acid is broken down releasing hydrogen ions and the remaining salt combines with sodium or potassium ions to make lactate
Why is there an increased acidity as lactate accumulates?
There are more hydrogen ions which decreases the pH
What effect does an increased acidity have on the body?
It slows down enzyme activity which slows the breakdown of glycogen causing fatigue
What does OBLA stand for?
Onset of blood lactate accumulation
What is OBLA?
As exercise intensity increases the body cannot produce enough oxygen to breakdown lactate so it builds up
What is the lactate threshold?
Moving from aerobic to anaerobic zones and the point at which lactate rapidly accumulates
Why is there no lactate accumulation during aerobic exercise?
Lactic acid is still produced but there is enough oxygen to break it down
What does measuring OBLA give us?
An indication of a person endurance capacity
Can the lactate threshold be altered?
Yes, through training, diet etc the lactate threshold can be delayed which delays OBLA
How is lactate threshold expressed?
As a % of VO2 max
What effect do high fitness levels have on lactate threshold and OBLA?
The fitter you are the higher the lactate threshold delaying OBLA so you can work harder for longer
What test shows OBLA?
The multistage fitness test
What are the factors affecting the rate if lactate accumulation?
- exercise intensity = higher the intensity the quicker lactate accumulates
- muscle fibre type = use of type 1 fibres slows rate of lactate accumulation
- rate of blood lactate removal = the more lactate removed the less accumulation so less fatigue
- respiratory exchange ratio = higher rate of gas exchange more oxygen to remove lactate less accumulation
- fitness of performer = increased fitness levels delay lactate threshold so lactate accumulation is delayed
How do you increase tolerance to lactate?
Years of training
What does buffering allow?
Increased rate of lactate removal so there is lower lactate levels
How does buffering work?
Absorbs the lactate so they can work at higher intensities for longer without fatiguing
What physiological adaptations occur to increase lactic acid tolerance?
More mitochondria, more oxidative enzymes, increased capillary density and more myoglobin
What are the factors affecting VO2 max?
Gender, age, body composition, lifestyle choices, genetics, training and physiological factors
What is measuring energy expenditure?
Measuring how much energy is released and can be used to identify fitness levels
What is the indirect calorimetry test?
- measures how much carbon dioxide is produced and how much oxygen is consumed
- allows us to identify what substrates are being used (CP, glycogen or fats)
- accurate estimate
What is lactate sampling?
- taking a blood sample and testing the lactate concentration
- accurate and objective
What is the VO2 max test/direct gas analysis?
- measures concentration of oxygen inspired and carbon dioxide expired in a lab
- involves increasing intensity of exercise until exhaustion
What is the respiratory exchange ration (RER)?
- ratio of oxygen consumed to carbon dioxide produced
- carbon dioxide expired per minute / oxygen inspired per minute
- value close to 1 = use of carbohydrates (aerobic)
- value around 0.7 = use of fats (aerobic)
- value above 1 = anaerobic
What is altitude training?
- training 2500m+ in low ppO2
- reduced diffusion gradient so trains body to work anaerobically for longer and delays the anaerobic threshold
What are the strengths of altitude training?
- increased number of red blood cells
- increased capillarisation
- increased ability to work with lactate
What are the disadvantages of altitude training?
- home sickness
- adaptations lost quickly
- altitude sickness
What is high intensity interval training (HIIT)?
- trains both aerobic and anaerobic systems
- periods of work (anaerobic) followed by periods of rest (aerobic)
- can adjust the variables duration of rest/exercise, speed and number of intervals
What is plyometric training?
- develops power
- anaerobic, high intensity explosive activities
- fast twitch muscle fibres
What is SAQ training?
- speed, agility and quickness
- improves multi directional movement
- invasion games players
- anaerobic