Chapter 12 - Chronic adaptations to training Flashcards
U4 AOS2
12.1 - Chronic adapatations to training
Chronic training adaptations
The body’s long-term responses of the cardiovascular, respiratory & muscular systems that develop over a periof of time when training is repeated regularly
- training should occur over an extended period - 3x a week for minimum 6-8 weeks
- adaptations occus when the body responds through making specific changes to cope w demands of exercise
- retainined unless training ceases - body gradually reverts to pre-training levels (reversibility or detraining)
- dependent on:
- type & method undertaken: type of adaptations depend on & are specific to the type of training - if the training is aerobic, anaerobic or resistance (SAID principle - Specific Adaptations to Imposed Demands)
- frequency, duration/time & intensity: the greater these are, the more pronounced the adaptations. diminishing returns & overtraining need to be considered
- individual capacities & herediatry factors: VO2max, muscle-fibre type distribution
12.1 - Chronic adapatations to training
Chronic adaptations to aerobic training
- minimun training is 6 weeks - more evident after 12
- increase efficiency of delivering larger O2 quantities - cardiovascular increase blood flow & distribution of O2 to muscles
- continuous, fartlek, long interval & HIIT
- can be done through circuit & resistance training if designed for aerobic & muscular endurance
- increase ability to aerobically produce ATP (Economy)
12.1 - Chronic adapatations to training
Chronic adaptations to aerobic training
Economy
Economy: describes the quantity of O2 (mL/kg/min) required to generate movement at any given speed or intensity
- O2 delivery effectiveness is the most significant factor
- O2 delivery depends on:
- lungs ability to ventilate large volumes of O2
- bloods ability to exchange O2 at the lungs
- hearts ability to pump large quantites of blood to muscles
- muscles ability to extract O2 from blood (myoglobin)
- muscles ability to use O2 to breakdown fuel for ATP production
12.1 - Chronic adapatations to training
Chronic adaptations to anaerobic training
- minimum training is 6 weeks
- greatest adaptations occur in muscular system
- designed for hypertrophy - enables greater force production, power output, strength & speed
- further adaptaion at muscle tissue level improve anaerobic capacity & metaboic by-product tolerance
- short & immediate interval training, plyometrics & circuit training (esigned w/ anaerobic exercises)
- strength & power resistance training
12.1 - Chronic adapatations to training
Chronic adaptations to resistance training
- muscle size is a signifiacnt contributer to muscle strength
- initial stages increases in strength are due to neural adaptations - sibstantial impact for first 8-10weeks
- after 10 weeks muscular hypertrophy is the predominant factor contributing
Muscular hypertrophy: the increase in the cross-sectional area of a muscle - an increase in muscle size
12.2 - Chronic adaptations to aerobic training: cardiovascular
Increased left ventricle size & volume
- trainining results in cardiac hypertrophy
cardical hypertrophy: an enlargement of the heart muscle as a result of training - increased size increases volume
- results in increase in SV & Q - allows more blood to leave heart & deliver O2 to muscles
12.2 - Chronic adaptations to aerobic training: cardiovascular
Increased capillarisation of the heart muscle
capillarisation: an increase in the capillary density and blood flow to skeletal or cardiac muscle as a result of aerobic training
- increases blood supply & O2 to the heart to beat more strongly & effectively during exercise & rest
12.2 - Chronic adaptations to aerobic training: cardiovascular
Increased SV
SV: the amount of blood ejected from the left ventricle with each contraction of the heart
- cardiac hypertophy, reduced systemic peripheral resistance, greater blood volume, increased venous return & increased stretch of ventricle all contribute
- allows for greater O2 delievery to muscles
- able to work at higher intensities for longer w/ fewer fatiguing factors
12.2 - Chronic adaptations to aerobic training: cardiovascular
Decreased resting & submaximal HR & faster recovery HR
- HR is a good indicator of aerobic fitness
- effect on MHR is minimal - largely affected by age & genetics
12.2 - Chronic adaptations to aerobic training: cardiovascular
Decreased resting HR
- amount of O2 needed at rest doesnt change
- at rest 5L of blood/min circulates
- Q: the amount of blood ejected from the left ventricle per min
- if individual has a greater SV the heart rate doesnt need to beat as frequently to supply required blood flow
RHR: the number of bpm whle the body is at rest - lower RHR = greater aerobic fitness
12.2 - Chronic adaptations to aerobic training: cardiovascular
Decreased HR during submaximal workloads
- have lower HRs during submaximal activity
- result of increased SV
- results in slower increase in HR during exercise & faster attainment of steady state
12.2 - Chronic adaptations to aerobic training: cardiovascular
Faster HR recovery rates
- HR will return to pre-exercise levels quicker after maximal & submaximal work
- due to a greater effiency of cardiovascular system in aerobic energy production
12.2 - Chronic adaptations to aerobic training: cardiovascular
Increased Q during maximal exercise
- unchanged @ rest & submaximal exercise
- increases due to increase in SV
12.2 - Chronic adaptations to aerobic training: cardiovascular
Decreased blood pressure
- can lower BP
- systolic & diastolic decrease during rest & exercise during training
- helps reduce resistance to blood flow & strain on the hear
- decreases risk of heart attack
12.2 - Chronic adaptations to aerobic training: cardiovascular
Increased cappilaristation of skeletal muscle
- allows increased blood flow - more O2 & nutrients to muscles & increased removal of metabolic by-products
- one of most significant factors leading to VO2max increase
- diffusion of O2 from capillaries to mitochondria is a major factor in maximising the muscles rate of O2 consumption
12.2 - Chronic adaptations to aerobic training: cardiovascular
Increased blood volume
- total blood volume risses by up to 25%
- RBC increase in number - greater haemoglobin content & O2 carrying capacity rises
- more O2 is deleivered to muscles and used
- blood plasma volume increases - reduces viscosity of blood, allowing it to flow smoothly through blood vessels
- improves blood flow
- enhances O2 delivery to muscles
- increases thermoregulation capacity
12.2 - Chronic adaptations to aerobic training: cardiovascular
Adaptations
- increased left ventricle size & volume
- Increased capillarisation of the heart
- increased SV
- decrested resting & submaximal HR & faster recovery HR
- decreased RHR
- decreased HR during submaximal work
- faster HR recovery rates
- increased Q in maximal exercise
- decreased BP
- increased capillaristaion of skeletal muscle
- increased blood volume
12.3 - Chronic adaptations to aerobic training: respiratory
Increased pullmonary ventilation during maximal exercise
- V is reduced at rest & submaximak exercise due to improved O2 extraction
- during maximal exercise V increases due to increase in TV & RR
V: the amount of air that is inspired or expire per min by the lungs. V = TV x RR
TV: the amount of air inspired & expired by the lungs per breathe
RR: the amount of times a person breathes in and out per min
12.3 - Chronic adaptations to aerobic training: respiratory
Increased TV
- due to increased strength & endurance of respiratory muscles - more air can be inhaled/exhaled
- allows more O2 to be diffused into surrounding alveoli capilaries & delivered to muscles
12.3 - Chronic adaptations to aerobic training: respiratory
Decreased resting & submaximal RR
- increased pulmonary function & O2 extraction from alveoli to suurounding capillaries
12.3 - Chronic adaptations to aerobic training: respiratory
Increased pulmonary diffusion
Pulmonary diffusion: the movement of O2 and CO2 from high concentration to low concentration between the alveoli & the surrounding cappilaries
- training increases SA of alveoli
- allowd for more O2 & CO2 exchange
- oncrease in this & V allows more O2 to be inhaled, extracted & transported to muscles
12.3 - Chronic adaptations to aerobic training: respiratory
Adaptations
- Increased pulmonary V during maximal exercise
- increased TV
- decreased resting & submaximal RR
increased pulmonary diffusion
12.4 - Chronic adaptations to aerobic training: muscular
Training methods
- continuous
- fartlek
- long interval
- HIIT
- hip rep, low weight resistance training
12.4 - Chronic adaptations to aerobic training: muscular
Increased O2 utilisation
mitochondria & myoglobin
- enhances the body’s ability to attract O2 into muscle cells for ATP resynthesis
- more O2 initially surrounds muscle through increase capillarisation - mitochondria & myoglobin utilise it for ATP resynthesis
Mitochondria: cell structures in which oxidative ATP resynthesis takes place
Myoglobin: an O2 binding protein in skeletal muscle cells that attracts O2 from the bloodstream & shuttles it to the mitochondria in the muscles for aerobic energy production
12.4 - Chronic adaptations to aerobic training: muscular
Increased O2 utilisation
Increased mitochondria size & number, increased myoglobin stores
- process occurs in the following ways:
- increased mitochondria size & number: sites for aerobic ATP resynthesis & where glycogen/triglyceride stores are oxidised. The greater the number/size the greater the oxidisation of fuels to aerobically produce ATP
- increased myoglobin stores: increases in myoglobin content increase ability to extract and delvier O2 to the mitochondria
12.4 - Chronic adaptations to aerobic training: muscular
Increased a-VO2 diff
a-VO2 diff: a measure of the difference in the concentration of O2 in the arterial blood and the concentration of O2 in the venous blood, measured in mL O2/100mL of blood
- extract more O2 during exercise - trained athletes will extract more
- due to increased mitochondria number/size & myoglobin stores
12.4 - Chronic adaptations to aerobic training: muscular
Increased muscular fuel stores & oxidative enzymes
Oxidative enzymes: enzymes that, w/ the use of O2, speed up the breakdown of nutrients to resynthesise ATP
- increases muscular storage of glycogen/triglycerides in slow-twitch muscle fibres & ozidarive enzymes responsible for metabolising these
- decreases relience on anaerobic glycolysis until higher intensitis
12.4 - Chronic adaptations to aerobic training: muscular
Increased oxidation of glucose & triglycerides
- other muscular adaptations result in an increase int he capacity of muscular fibres to oxidise glucose & triglycerides
- capacity of aerobic system to metabolise fuels is increased
- increased oxidation of fats as fuel at any intensity means there is less reliance of glycogen - due to increased triglyceride storgae & enxymes involved in their metabolism
Glycogen sparing: the process whereby glycogen stores are not used as early in an exercise bout due to the increased ability to use triglycerides to produce energy. this delays the depletion of these stores, and thereby delays the tome to exhaustion due to glycogen depletion - allows sustainability of a higher intensity
12.4 - Chronic adaptations to aerobic training: muscular
Adaptation of muscle fibre types
- type 2A fibres can take on type 1 characteristics from endurance training
- type 2B fibres are recruited more in a manner that represents tpe 2A
- slow twitch increase in cross-sectionalarea - dependent on intensity & duration
- muscles are made of all 3 types - genetic makeup determines proportions
- type 2B transformation is very gradual - can take years
- transformed fibres show slight increase in diameter, mitochondria & cappilaries - not a change in fibre tupe
12.4 - Chronic adaptations to aerobic training: muscular
Adaptation of muscle fibre types
Type 1 slow-twitch oxidative fibres
are red, and have a high capacity to generate ATP by oxidative merabolic processes. they split ATP at a slow rate, have a slow contraction velocity & are very resistant to fatigue
- contain large amounts of myoglobin
- large amounts of mitochondria & blood capillaries
Colour: Red
Used for: Aerobic
Fibre size: Small
12.4 - Chronic adaptations to aerobic training: muscular
Adaptation of muscle fibre types
Type 2A fast-twitch oxidative fibres
are redm abd gave a very high capacity for generating ATP by oxidative metabolic processes. they split ATP at a very rapid rate, have a fast contraction velocity and are resistant to fatigue
- large amounts of myoglobin
- larder numbers of mitochondria & blood capillaries
Colour: Red
Used for: Anaerobic (long-term)
Fibre size: Medium
12.4 - Chronic adaptations to aerobic training: muscular
Adaptation of muscle fibre types
Type 2B fast-twitch glycolytic fibres
are white, and are geared to generate ATP by anaerobic metabolic processes. they split ATP at a very rapid rate, have a fast contraction velocity & fatigue easily
- low myoglobin content
- relativey few mitochondria and blood capillaries
- large amounts of glycogen
Colour: White
Used for: Anaerobic (short-term)
Fibre size: Large
12.4 - Chronic adaptations to aerobic training: muscular
Adaptations
- increased O2 utilisation
- increased a-VO2 diff
- increased muscular fuel stores & oxidative enzymes
- increased oxidation of glucose & triglycerides
- adaptation of muscle fibre types
12.5 - Chronic adaptations to aerobic training: all 3 systems
Increased VO2 max
VO2max: the max amount of O2 per min that can be taken up, transported to and utilised by the body for energy production
- improvemtns can range from 5-30%
- due to other adaptations:
- increased Q
- increased RBC number
- increased a-VO2diff
- increased capillarisation in skeletal muscles
- greater O2 extraction by myoglobin
- a combination of Q & a-VO2 diff - VO2max = Q x a-VO2 diff
- relative consideres body weight - mL/kg/min
- absolute doesnt - L/min (cant make comparinsons)
12.5 - Chronic adaptations to aerobic training: all 3 systems
Increased LIP
LIP: represents the ighest intensity point where there is a balance between lactate production & removal from the blood
- result of adaptations that improve O2 deliverym use & economy
- higher LIP = faster aerobic system
- H+ & lactic acid accumulation is delayed
- often expressed as percentage of VO2 max or MHR
- increased mitochondria size & density allows for greater ATP resynthesis & increased ability to remove lactate via:
- some lactate is re-converted to pyruvate for immediate oxidation in the mitochondria
- some lactate is transported out of cell into blood
- most blood lactate is oxidised by other muscles
- some blood lactate os converted to glucose or glycogen in liver
12.5 - Chronic adaptations to aerobic training: all 3 systems
Adaptations
- increased VO2 max
- increased LIP
12.6 - Chronic adaptations to anaerobic training
training methods
- short & intermediate interval training
- plyometrics
- circuit
- resistance (strength & power)
12.6 - Chronic adaptations to anaerobic training
muscular hypertrophy
- lead to significant enlargement of muscle fibres - mainly types 2A & 2B
- occurs because of an increased size & number of myofibrils per muscle fibre & increased amounts of actin & myosin
Myofibrils: small fibres that run through each muscle fibre
12.6 - Chronic adaptations to anaerobic training
increased muscular stores of ATP, ATPase, creatine kinase enzymes & CP
- muscular hypertrophy is accompanied by increased muscular sotres of ATP & CP
- increases capacity of ATP-CP system
- improves speed, strength & power
- increase in the enzyme needed to break down & resynthesis ATP - ATPase
ATPase: responsible for breaking down ATP to release energy for muscular contraction
Creatine kinase: initiates breakdown of CP to provide energy to resynthesise ATP at a fast rate
12.6 - Chronic adaptations to anaerobic training
Increased glycolytic capacity
- enhanced muscular storgae of glycogen & increases in levels of glycolytic enzymes
- enhances anaerobic glycolysis system capacity
12.6 - Chronic adaptations to anaerobic training
Increase in the ability to recruit more motor units
Motor units: consists of one motor neuron and all of the muscle fibres that it inneravates
- aboility of nerve axons to innervate corresponding muscular fibres increases
- greater number of motor units recruited allows them to produce greater strength & power
12.6 - Chronic adaptations to anaerobic training
increase in lactate tolerance
- anaerobic work involves wroking above LIP
- body learns to tolerate the increased levels of lactic acid & increases its buffering capacity
buffering capactiy: the ability of the muscle cell buffers to resist changes in pH - training increases the muscles ability to buffer acid accumulating from H+
H+: makes the muscle acidic and will eventually aftigue muscle function - increase in tolerance prevents fatigue onset & allows anaerobic ATP production at a faster rate
12.6 - Chronic adaptations to anaerobic training
cardiac hypertrophy
- increase in thickness of the ventricular walls
- a more forcefull contraction occurs causing a more forceful ejection of blood - little to no change in SV
12.6 - Chronic adaptations to anaerobic training
Adaptations
- muscular hypertrophy
- increased muscular stores of ATP, ATPase, creatine kinase enzymes and CP
- increased glycolytic capacity
- increase in the ability to recruit more motor units
- increase in lactate tolerance
- cardiac hypetrophy
12.7 - Chronic adaptations to resistance training: neuromuscular
training
- power & strength resistance training induces anaerobic adaptations
- endurance resistance trainin induces aerobic adaptations
- long-term training will induce adaptations in neuromuscular system
- increases in strength depend on muscle group trainined, type of resistance training & intensity
12.7 - Chronic adaptations to resistance training: neuromuscular
increases in muscle size & change in muscle structure
- increases in cross-sectional area of the muscle results from increase in cross-sectional area of each individual muscle fibre
- hypertrophy of each fibre is due to increase in quanity of actin & myosin, number & size of myofibrils & amount of connective tissue
fibre hyperplasia: an increase in the number of fibres w/in a muscle - contributes to the increase in muscle size
12.7 - Chronic adaptations to resistance training: neuromuscular
muscle fibre type adaptations
- each single motor unit contains only 1 type of muscle fibre
- tyoe 2 show greater increases in size - particularly w/ higher loads
size principle: the principle by which motor units are recruited in order of their size from smallest to largest - suggests all motor unit types would be recruited for heavy loads & therefore a greater involvement of type 2 fibres
12.7 - Chronic adaptations to resistance training: neuromuscular
neural control
- in absence of hypertrophy neural adaptations play a critical role in increased forve production
- increased synchronisation & recruitment of motor unit increases firing rate & reduces inhibitory signals - contributes to strength gains
12.7 - Chronic adaptations to resistance training: neuromuscular
increased synchronisation of motor units
- makes a number of different motor units able to fire at the same time
- ability to recruit more units at the same time & stimulate larger ones creates a more powerful muscular contraction w/ greater force application
12.7 - Chronic adaptations to resistance training: neuromuscular
increased firing rate (rate coding) of motor units
- combo of motor unit recruitment & firing rate (rate coding) is knwon as neural drive
rate coding: referes to the frequency of impulses sent to a muscle - increases the rate of force development - how quickly a muscle can contract maximally, rather than increase force
- beneficial for rapd ballistic movements where max force is needed in a very short time
12.7 - Chronic adaptations to resistance training: neuromuscular
reduction in inhibitory signals
- role is to provide an improtant protective reflex - limits excessive force generation in a muscle
- training can gradually reduce this & allow for a greater force production
- improved coordination of the agonist, antagonist & synergist allows this
agonist: the prime mover of the muscle action. it causes the movement to occur
antagonist: works in opposition to the agonist muscle
synergist: muscles stabilsing movements to maintain cotrol w/in desired ROM
12.7 - Chronic adaptations to resistance training: neuromuscular
Adaptations
- increase in muscle size & changes in the structure
- muscle fibre type adaptations
- neural control
- increased synchronisation of motor units
- increased firing rate (rate coding) of motor units
- reduction in inhibitory signals
