Principle of AdaptationTraining Adaptations

Principle of AdaptationAthletes train to adapt their bodies to a particular

sport/activity.Training should be; Specific to their sport Specific to the desired outcome as a result of

adaptations.SAID PrincipleS = Specific A = Adaptation I = Imposed D =

DemandsAdaptation = “a long-term physiological change in

response to training loads that allows the body to meet new demands.

Stress on the body causes adaptations.A plateau occurs when the training load is not

sufficient to cause stress.Adaptations can be classified as acute and chronic;Acute – Immediate physiological response to exercise

which last the duration of the exercise session. Type of training not important.

Chronic – Long-term adaptations to exercise. In this chapter, we will focus on chronic changes.

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Anaerobic and Aerobic AdaptationsTraining Adaptations

Anaerobic Energy System AdaptationsAnaerobicTraining the ATP-PC and lactic acid systems cause; Increased levels of anaerobic enzymes and fuels Increase in glycolytic capacity Improvements at the muscular level in both

systemsAerobicImprovements in; Oxygen uptake Transport and utilisation of oxygen Fat breakdown as a fuel Fatty acid oxidation and respiratory ATP

production Lactate Infection Point Reduced carbohydrate use during sub-maximal

exercise Increased use of blood glucose – assisting in

glycogen sparing. Increased capillarisation, mitochondria density and

oxidative enzymes.VCE Physical Education - Unit 4

Cardiovascular Training AdaptationsTraining Adaptations

Cardiovascular Training Cardiac Hypertrophy - Heart increases (Left ventricle) in size

as a result of training. This increases the stroke volume (SV) Increased capillarisation - (Coronary blood supply) of the

heart – increases blood flow to the heart. Increased stroke volume - thus reducing HR. Lowered resting heart rate (Increase in SV causes a decrease

in HR when Q is constant – approx 5 litres) Lower heart rate during sub-maximal workloads – Due to

increased SV. Improved heart-rate recovery rates – Due to increased SV Increases cardiac output at maximum workload – Constant at

rest, but Q can reach up to 30L/min in elite athletes. Cardiac Output = Stroke Volume x Heart Rate Q = SV x HR

Example Q = 5L SV = Q/HRBefore training HR = 71bpm therefore the SV = 0.07L/beatAfter training program HR=50bpm.SV now = 0.1L/beat

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Cardiovascular Training

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•Lower blood pressure – relieves hypertension by lowering resistance in the vessels•Arterio-venous oxygen difference - increases as athlete is able to use oxygen from arteries more effectively•Increased plasma, blood volume and haemoglobin levels•Increased capillarisation of skeletal muscle

•Decreased blood cholesterol, triglycerides ad Low Density Lipoproteins (LDP). These substances are associated with coronary heart disease.Increased high density lipoproteins (HDL) – Ratio of HDL to LDL increases, which is important for heart health.Increased redistribution of blood – Training can lead to a 20% increase in blood flow to working muscles.

Respiratory Training AdaptationsTraining Adaptations

Respiratory Training Adaptations Decreased minute ventilation- Lungs become more

efficient as a result of training. Ventilation is therefore reduced at sub-maximal workloads.

Increased pulmonary diffusion – oxygen is more readily extracted from the alveoli

Increased tidal volume (Amount of air inspired and expired during breathing)

Ventilatory musculature – Muscles responsible for breathing require less oxygen.

Improved lung function –due to improved lung volume and alveolar capacity surface area.

Aerobic capacity – Improves due to an increase in oxygen supply to the working muscles.

See table 11.4 p.273Increased VO2 max – Due to; Increase in cardiac output, Increase in RBC numbers, Increase in a-VO2 diff Increase in muscle capillarisation Improved oxygen extraction.

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Oxygen extraction: a-V02 difference

a-V02 difference = Arteriovenous oxygen difference: “difference in oxygen consumption when comparing that in the arterioles to the venules, and an indirect measure of how much oxygen muscles are using”

An increase in a-V02 difference results in more blood being pumped to active muscles (especially slow-twitch)

Muscle fibres better at extracting and processing oxygen as a result of increased mitochondria numbers, more oxidative enzymes and increased levels of myoglobin.

All of this is due to the oxygen demands of the muscles

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12 mL/100mL

18 mL/100mL

Muscular Training AdaptationsTraining Adaptations

Muscular Training AdaptationsAthletes need to use specific training methods to

cause muscular adaptations for their sport.Aerobic – Trains the slow twitch (Type I) fibres.Anaerobic – Trains fast twitch (Type II) fibres. Muscle fibre type and percentage that make up

the body Muscle fibre type can change, eg for elite

endurance athletes from 70-90% Genetics a big advantage to start with x amount

of fibre percentage You are born with x amount of fast and slow

twitch fibres. BUT you can train and gain more of one type.

MYTH – “with training you can change from fast twitch to slow twitch or vice versa.” IMPOSSIBLEHOWEVER – fast twitch fibres have been

known to take on slow twitch characteristics in response to aerobic training

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Aerobic (Muscular) Increased oxygen utilisation – Increased size and number

and density of mitochondria Increased myoglobin stores. Increased muscular fuel stores ie.Glycogen, fatty acids,

triglycerides and oxidative enzymes. Increased capillary density to slow twitch fibres. Increased use of fat at sub-maximal levels. Increased stores and use of intramuscular triglycerides. Increased oxidation of glucose and fats – Ability to

metabolise and extract energy has improved. The body can therefore use ‘glycogen sparing’.

Decreased use of lactic acid system Some muscle fibre adaptation.

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Anaerobic (Muscular)Muscular Hypertrophy – Enlargement of the fast twitch

muscle fibres Increased muscular stores of ATP, PC, creatine and glycogen. Increased ATP-PC splitting and resynthesis of enzymes Increased glycolytic capacity – Enhances lactic acid

systems ability to use glycogen. Cardiac hypertrophy – Increases contraction forces

exerted by the left ventricle in the heart.

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Anaerobic (Muscular) Increased contractile proteins in muscles. Increased myosin ATPase – Molecule responsible for

splitting ATP into ADP Increased muscle buffering capacity – Muscles able to

tolerate higher levels of fatiguing productsMuscle hyperplasia –Research in animals suggest that

new muscle fibres may form under stress.Other – Increase in strength of connective tissue,

number of motor units, speed on nerve impulses and muscular contraction speed.

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Adaptations

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Adaptations are ReversibleTraining Adaptations

Adaptations are ReversibleAdaptations are reduced and

then lost after stopping regular training.

The reversibility principle applies when an athlete becomes inactive.

As a result, athletes need to undertake a vigorous pre-season months before the in-season starts.

Therefore maintenance in the off-season is required to minimise reversing the adaptations. VCE Physical Education - Unit 4