Chronic Adaptations to Training

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Chronic adaptations to

training.

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Chronic adaptations to training.

– What is Chronic adaptations to training?– How long does it take?– Read Chapter 11 Nelson Physical Education

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Chronic adaptations to training

• Athletes train to adapt their bodies to a particular sport/activity.

• These changes or adaptations in the body is specific to the training method/s applied

• Adaptation = “a long-term physiological change in response to training loads that allows the body to meet new demands.

• If training load is not sufficient to challenge the body, no adaptations occur and a plateau will occur.

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Aerobic and anaerobic training methods

Anaerobic training methods

Aerobic training methods

Plyometrics or ballistic stretching

Continuous

Weights/resistance Fartlek

Interval (short/intermediate)

Interval

Circuit (high work-rest ratio)

Circuit (low work-rest ratio)

Sprint Flexibility

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Typical Metabolic and physiological values for healthy trained and untrained men

Variable Untrained Trained %age diff

Glycogen (mM) 85 120 41

Mitochondria Volume (% Muscle cell)

2.15 8 272

Resting ATP (mM) 3 6 100

Resting PC (mM) 11 18 64

Aerobic enzymes (mM) 5-10 15-20 133

Max Lactate (mM) 110 150 36

Max stroke Vol (mL) 120 180 50

Max cardiac output (L/min) 20 30-40 75

Resting HR (bpm) 70 40 -43

VO2 max (mL/kg/min) 30-40 65-80 107

Blood Volume (L) 4.7 6 28

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Aerobic Energy Systems Adaptations

• ↑’ed levels of anaerobic enzymes and fuels including;– ATP– PC– Glycogen

• ↑ in glycolytic capacity – “the ability to break down glycogen via key enzymes that facilitate glycolysis”

• ↑’ed amounts and activity levels of enzymes involved in anaerobic glycolysis (mainly fast twitch fibres)

• ↑’ed ability to produce blood lactate during maximal exercise. Results in an increase in glycogen stores and glycolytic enzymes.

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Aerobic Energy Systems Adaptations

• ↑ in oxygen uptake, transport and utilisation• ↑’ed enhanced fat breakdown (from an ↑ in fat

metabolising and ↑’ed fat mobilising enzymes)• Improved fatty acid oxidation and respiratory

ATP production• ↑ reduced CHO use during sub-maximal

exercise.

Therefore these factors assist in glycogen sparing which leads to better endurance

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Aerobic training also causes important changes in the anaerobic threshold!– Ie the point where LA beings to accumulate. Generally

this id at 85% of Max HR. But with the aerobic training comes;• ↑’ed capillarisation• ↑’ed mitochondria density• ↑’ed oxidative enzymes• Structural changes to the cardiovascular system.

Therefore the anaerobic threshold can improve closer to 90% of Max HR.

Aerobic Energy Systems Adaptations

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Aerobic Energy Systems Adaptations

OBLA – Onset of Blood Lactate concentration shows and an increase equal to 4.0mM

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Trained Athlete

Question 1

Put an X on the point of Lactic threshold.

Question 2

What would the red line (blood lactate) look like for an untrained athlete?

Question 3

Place a ▲ on the OBLA for both trained and untrained people

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Untrained Athlete

Lactic Threshold

OBLA

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Questions1. a. List 3 methods of training that will predominantly

bring about training adaptations to the aerobic system b. List 3 methods of training that will predominantly

bring about training adaptations to the anaerobic system

2. Under sub-maximal aerobic conditions explain why it is better to use Fats over CHO’s as a fuel source?

3. What is the relevance of anaerobic threshold? How does it respond to aerobic training?

4. Resting heart rate is one of the few variables that decrease as a result of training especially aerobically. It has been said that this is because the heart is more efficient. What does this mean?

5. What does the vascular system refer to?

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↑’ed oxygen delivery to working muscles due to;a. ↑’ed Plasmab. ↑’ed Haemoglobinc. ↑’ed Total blood volumed. ↑’ed ventricle sizee. ↑’ed venous returnf. ↑’ed myocardial contractility g. ↑’ed max stroke vol.h. ↑’ed max cardiac outputi. ↑’ed effectiveness of cardiac outputj. ↑’ed peripheral blood flowk. ↑’ed blood flow to working musclesl. ↑’ed capillarisation m. ↑’ed Arteriovenous oxygen difference (A-VO2 diff)

Cardiovascular Training adaptations

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Cardiovascular Training adaptations – Cardiac Hypertrophy

• Greatest improvements are attained in first 3 months. After 3 years of training only very slight improvement

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The heart muscle itself

P251. text

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Increased plasma, haemoglobin and myoglobin volumes

• Increased plasma, haemoglobin and myoglobin volumes contribute to improved oxygen transport and temperature regulation during exercise.

• Haemoglobin helps transport oxygen throughout blood vessels

• Myoglobin assists in moving oxygen from cell membranes to the mitochondria.

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Changes in Heart Rate

• Resting and sub-maximal HR’s will decrease as a result of aerobic training.

• Mainly due to – ↑ in stroke volume– ↑ in Q

• Therefore to supply the same amount of oxygen, the heart needs fewer beats per min. Therefore the heart becomes more efficient. It pumping the same amt of blood with fewer beats.

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Changes in Heart Rate

STROKE VOLUME

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Changes in Heart Rate

How much blood the heart is pumping out per minute.

So….

Which heart before/after training is working harder?

________________________________________

Why? _____________________________________________________

__________________________________________________________

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• Improved heart rate recovery– Trained individuals will return to resting HR’s

faster than an untrained individual.

Changes in Heart Rate

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Complete

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Increased Cardiac Output at maximum workloads

• Without training males; males 20-22 L/min and females 15-16 L/min.

• With training values have exceeded 30 L/min

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Blood Pressure

Reminder

Systolic Blood Pressure

Pressure on the arteries following contraction of ventricles as blood is pumped out of the heart

Diastolic Blood Pressure

Pressure in the arteries when the heart relaxes and ventricles fill with blood

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• The greatest changes occur with the systolic pressure. – This is a direct result of;

Improved capillarisation Improved elasticity of blood vessels↑’ed HDL’s (high-density lipoproteins, breaking

down fatty deposits/plaque built on inside of arterial walls)

• People with high Blood pressure place a high stress on the cardiovascular system.

Blood Pressure

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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 ↑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 ↑’ed mitochondria numbers, more oxidative enzymes and ↑’ed levels of myoglobin.

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

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a-V02 difference

12 mL/100mL

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a-V02 difference

18 mL/100mL

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Respiratory Adaptations

• Tidal volume – amount of air inspired and expired during normal breathing. Number per minute decreases at rest

• Minute Ventilation – at rest MV decreases, at Maximum 02 uptake MV increases to allow more air into the lunge and greater breathing frequency.

• Improved lung function – increased surface area for the gas exchange

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Respiratory Adaptations

• Aerobic capacity – “the maximum amount of oxygen the body can take in, transport and use”– can increase form 10-25% in the first 6

months with intense aerobic training.– Over 2 years can increase 40%.

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Respiratory Adaptations

Page 255 of text

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Questions1. Aerobic training improves VO2 max of athletes as

an adaptation to the training. List at least two changes that result in this improvement.

2. Activity 2 - page 255 of text3. Review questions 7-10

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Muscular Training Adaptations

Aerobic level

Anaerobic level

Vs

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Muscular Training Adaptations

• 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.” IMPOSSIBLE– HOWEVER – fast twitch fibres have been known to

take on slow twitch characteristics in response to aerobic training

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Muscular Training Adaptations - Anaerobic level

• Strength/power and speed training• Greatest adaptations occur at tissue level

• Muscular Hypertrophy– Fast twitch fibres (type II)– High intensity loads, low reps– Males have greater results due to presence of

testosterone

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Muscular Training Adaptations - Anaerobic level

• Increased energy substrate levels in muscle– ATP– CP– Glycogen

• Increased ATP-PC splitting and resynthesis– Mainly due to sprint training– Increase in the level of

enzymes responsible for this

Substances that are the most readily available fuel source of muscular energy

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Muscular Training Adaptations - Anaerobic level

• Increased Glycolytic capacity– Enzymes responsible for the breakdown of

glycogen show increased concentration– Sprint training

• Increased ventricle thickness - Don’t forget the heart is a muscle as well!

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Muscular Training Adaptations - Anaerobic level

• Increased contractile proteins in muscles– Strength training tends to add to the protein of the

muscle that generates tension hence greater force generated at any given speed

• Increased myosin ATPase– This is the enzyme that splits ATP to yield energy for

muscular contractions– More of this enzyme = more energy released allowing

contractions to occur at a quicker rate

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Muscular Training Adaptations - Anaerobic level

THANKS TO THE RESEARCH SCIENTISTS

• Increased muscle buffering– Greater LA tolerance is evident when vigorous anaerobic

training has taken place possibly due to body’s improved capacity for acid-base regulation

• Muscle hyperplasia (new fibres formed)– We knew that muscle fibres increased in size but

anaerobically they have been seen to also increase in numbervia longitudinal splitting

– Changes occur due to chronic overload to the skeletal muscle

NEW

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Muscular Training Adaptations - Aerobic level

• Increased Mitochondria density and number– Aerobic powerhouse of the body– Where ATP production occurs– Results in an increase in the capacity for aerobic

metabolism from oxidation of FFA’s and CHO for endurance work

– Mitochondria numbers can double under the right training

– NOTE: anaerobic resistance training will reduce this effect • Eg – Soccer players Vs AFL players

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Muscular Training Adaptations - Aerobic level

• Increased myoglobin stores– Similar to haemoglobin (transports oxygen in

the blood) Myoglobin provides intramuscular oxygen storage.

– More myoglobin = more oxygen can be stored at the muscles

– Hence more ATP production.

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Muscular Training Adaptations - Aerobic level

• Improved oxidative capacity Via increased oxidative enzymes (kreb’s cycle) – Faster ATP production

• Improved capillary density– Greater oxygen exchange due to greater

surface area available. – Improvements in VO2 max

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Muscular Training Adaptations - Aerobic level

• Increased use of Fats during sub-maximal exercise– To inhibit CHO use– Mainly during the first 30 minutes of exercise– More CHO hence glycogen available for later

during endurance performance– Glycogen sparing

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Muscular Training Adaptations - Aerobic level

• Increased stores and use of intramuscular triglycerides – (Triglycerides, which are chains of high-

energy fatty acids, provide much of the energy needed for cells to function.)

– Assists with glycogen sparing– Ideal fuel for low-intensity and sub-maximal

exercise

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Muscular Training Adaptations - Aerobic level

• Increased muscle glycogen synthase and storage–Glycogen synthase is the enzyme

responsible for converting glucose to glycogen.

–Aerobic glycolysis is faster and more efficient

–Therefore increase in performance

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Adaptations are reversible

• When an athlete ceases training they experience a rapid loss of their acquired adaptations.

• And endurance athlete confined to bed for 3 weeks can lose – Max stroke volume– Q– Aerobic capacity

1% per day

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Questions

1. What is the main difference between fast and slow twitch fibres?

2. Muscle hypertrophy occurs in response to both aerobic and anaerobic training. Briefly discuss what this means and how it brings about improved performance levels under each situation.

3. How do mitochondria bring about improved aerobic performances?

4. As a result of aerobic training, muscles ‘learn’ to make earlier and greater use of fats as a fuel (especially under sub-maximal exercise conditions). Explain how this leads to improved endurance performances.