VCE PE Unit 3 AOS 2

road to 90%?

Increased oxygen uptake (VO2)

As exercise intensity increases, oxygen uptake increases

Factors affecting oxygen uptake

• Age 

• Body size 

• Gender 

VO2 max

The VO2 max represents the maximum amount of oxygen able to be taken up by, transported to and utilised by the muscles in L/min

How to work out VO2 max

VO2 max = Q x a-VO2 difference 

What does EPOC stand for

Excess post-exercise oxygen consumption

3 stages of oxygen consumption

Oxygen deficit, steady state, EPOC

Oxygen deficit

The stage of exercise where oxygen supply does not meet the demands of the activity

Steady state

Is where oxygen supply meets the demands of the activity

EPOC

Is where oxygen supply remains above resting levels

Acute responses

When an athlete moves from rest to exercise, or increases their intensity of the movement

What do acute responses cause

• Increased oxygen demand 

• Increases energy demand (ATP) 

• Increased waste removal required  

HR

Heart rate

SV

Stroke volume

Q

Cardiac output

BP

Systolic blood pressure

a-VO2 diff

Arteriovenous oxygen difference

What is the cardiovascular system made from

Heart, blood vessels and blood

Cardiovascular system

To deliver oxygen to working muscles

How to calculate max HR

220 - age

Why does your HR increase

Increases to above resting level to meet the greater demand for oxygen to create energy

Anticipatory rise

When heart rate rises above resting level just before exercise 

Stroke volume

The amount of blood pumped from the left ventricle per beat

What is the average resting SV

80ml per beat for males, 60ml per beat for females 

Increased cardiac output

The amount of blood pumped out of the heart into the arterial system over 1 minute 

How to calculate cardiac output

Q=SV x HR

How does cardiac output increase

In direct proportion to increasing exercise intensity (VO2 max) 

Blood pressure

The measure of pressure exerted against the artery walls

Systolic blood pressure

Pressure on arterial walls when the heart beats

Diastolic blood pressure

Pressure on arterial walls when the heart relaxes

Vasodilation

Is where the blood vessels increase diameter to allow more blood flow (right)

Vasoconstriction

Is where the blood vessels decrease diameter to reduce blood flow (left)

Arteriovenous oxygen difference

Is a comparison of the concentration of oxygen in the arteries with the amount of oxygen in the veins

Respiratory system

Is made up of the nasal cavity, windpipes (trachea, bronchi, bronchioles) and alveoli

Purpose of the respiratory system

Take in air, and diffuse oxygen into the blood stream

Respiratory acute responses:

• Increases respiratory rate 

• Increased tidal volume 

• Increased ventilation 

• Increased pulmonary and muscle diffusion 

• Increased oxygen uptake (VO2) 

Ventilation

The amount of air breathed in and breathed out in one minute

Tidal volume (TV)

The amount of air breathed in and out in 1 breath

Respiratory rate (RR)

The number of breaths per minute

How to calculate ventilation (v)

Tidal volume (TV) x respiratory rate (RR)

Pulmonary diffusion

Is the process to describe the exchange of gases in the lungs

Diffusion

Is where a molecule moves from an area if higher concentration to an area of lower concentration

Muscular diffusion

Is the process to describe the exchange of gasses into and out of the muscle cells 

Muscular system

Is where ATP is broken down and resynthesized

Muscular system acute responses:

• Decreased fuels 

• Increased extraction and utilisation of oxygen at muscles 

• Increased muscle temperature  

• Increased production of wastes 

What does ATP stand for

Adenosine triphosphate

What is ATP

Is a high energy compound that muscle cells break down to release energy for contraction and movement

Types of energy fuels

CP, Carbohydrates, Fats, Proteins

Creatine phosphate (CP)

Is stored in limited quantities in the muscle cells

Carbohydrates

Are found in many foods we eat (Pasta, rice, potatoes)

Fats

Are found in many foods we eat and are essential for a balanced diet

Protein

Is essential for muscle growth and repair (chicken, beef)

ATP-CP system

Depletes after 8-10 seconds, is broken down Creatine Phosphate, restores 100% after 4 minutes,

Anaerobic glycolysis system

Broken down into glucose then pyruvate, after 10 seconds its the major supplier for 50-60 seconds of max effort 

Aerobic system

Used mostly during rest and sub-maximal exercise, become major supplier after 60 seconds of exercise

Factors affecting ATP demand

Duration, intensity

Continuous activity

A single event/race where the athlete doesn't stop for rest at any point (1500m)

Intermittent activity

A start stop game (basketball)

ATP-CP factors

• Fuel: Creatine phosphate 

• Rate: Very fast 

• Yield: Very small 

• Event type: Power/ explosive  

Anaerobic system factors

• Fuel: Glycogen/glucose 

• Rate: Fast 

• Yield: Small 

• Event type: Speed 

Aerobic system factors

• Fuel: Glycogen/glucose, carbs (fats once carbs deplete)  

• Rate: slow 

• Yield: Large 

• Event type: Endurance 

Types of fatigue

Fuel depletion, Thermoregulation, Accumulation of metabolic By-Products

Fuel depletion

CP depletion, Depletion of glycogen stores during long-duration exercise

Accumulation of metabolic by-products

Accumulation of H⁺ ions in muscles 

Thermoregulation

Increase in core body temperature

How long does it take for CP to deplete

Around 10 seconds of high intensity activity

How long does it take for glycogen to deplete

90-120 minutes of exercise (resulting in fats as main fuel)

Lactate inflection point (LIP)

The last point where lactate removal is equal to lactate production

Passive recovery

Allowing your body to rest (sitting, lying down). Used to replenishe muscle ATP and CP 

How long does it take CP to replenish: 

• 70% after 30 seconds 

• 87% after 60 seconds 

• 98% after 3 minutes 

Active recovery

Low intensity exercise immediately after training (walking, light jog)

What can carbs help with

Replenish muscle glycogen levels, faster recovery

What can protein help with

Muscle growth, faster recovery

What can cause thermoregulation

Dehydration

Cardiovascular acute responses

• Increased heart rate 

• Increased blood pressure  

• Increased stroke volume 

• Increased cardiac output