Exercise Physiology

Question 1

Oxygen consumption

Answer 1

Resting level of oxygen consumption:
SV, HR and breathing rate is low at rest
0-5:
Oxygen deficit - started activity
More oxygen required by working muscles that can be supplied until HR and BP catch up with initial start of activity
Connections between aerobic and aneorobic exercise

Question 2

Onset

Answer 2

02 consumption rises exponentially for the first few minutes
Fast component of exercise 02 consumption

Question 3

Plateau

Answer 3

Attained at 3-4 minutes

Question 4

Continued exercise: stable, steady state

Answer 4

Remain stable for duration of effort
Balance between energy required and ATP produced by a aerobic metabolism
No blood lactate accumulates

Question 5

What is the consequence of continued exercise

Answer 5

Fluid loss
Electrolyte depletion
Glycogen store depletion

Question 6

Elite athletes

Answer 6

High capacity of central circulation to deliver oxygen to active muscles
High capacity of active muscles to use o2

Question 7

What does pericardium limit?

Answer 7

Maximal oxygen consumption by limiting stroke volume and cardiac output during maximal response

Question 8

What is maximal oxygen consumption limited by?

Answer 8

Oxygen transport capacity of the cardiovascular system

Question 9

Define oxygen deficit

Answer 9

Difference between oxygen consumption during exercise and total that would have been consumed had steady rate O2 consumption had been achieved from start

Question 10

What is the immediate source of energy

Answer 10

Anaeorbic glycolysis

Hydrolysis of high-energy phosphate ATP and PcR

Question 11

What is recovery

Answer 11

How long it takes to return to pre-exercise oxygen consumption
Higher intensity of exercise produce more anaerobic energy transfer
Higher blood lactate
Higher BT

Question 12

Light exercise

Answer 12

Aerobic

Rapid attainment if steady rate oxygen consumption

Question 13

Moderate-intense exercise

Answer 13

More anaerobic energy transfer
Longer time to achieve steady-rate oxygen consumption
Larger oxygen debt
Recovery takes longer

Question 14

What is fatigue?

Answer 14

Depletion of all ATP
Myoglobin has lost all O2
Glucose and glycogen depleted
High accumulated levels of lactic acid

Question 15

What is EPOC

Answer 15

Breathing fast and deep following exercise to increase the amount of oxygen in the body to return the body to its pre-exercise state

Question 16

O2 deficit

Answer 16

How much of your effort was aneorbic

Question 17

Steady-state oxygen consumption

Answer 17

volume of oxygen consumed whilst exercising/during the event

Question 18

Fast component of EPOC

Answer 18

What happens after 2-3 minutes after event
Uses additional 1-4 litres of oxygen
Resynthesise all ATP and PC
Replenish all myoglobin with oxygen
Synthesise 50% of PC stores within first 30 seconds

Question 19

Slow component of EPOC

Answer 19

Removal of lactic acid
Maintenance of ventilation, circulation and body temperature
Require 5-8L of oxygen

Question 20

Why does temperature take time to recover post exercise?

Answer 20

Higher temperature - more chemical reaction

More oxygen consumed

Question 21

What does recovery depend on?

Answer 21

Activity:
Type,
Duration of exercise

Question 22

What is VO2 max?

Answer 22

Maximum volume of oxygen used/ utilised by the muscles per minute
Measured in: ml/min/kg

Question 23

Factors affecting VO2max?

Answer 23

Cardiac hypertrophy - Increase stroke volume and cardiac output
Increased haemoglobin levels
Increased capillary density
High percentage of slow twitch muscle fibres

Question 24

Factors affecting V02 max

Answer 24

Age - decline from 25 years (1% per year) - lost elasticity of heart - less diffusion of oxygen into lungs and muscles

Gender: males higher than females (higher body fat and smaller lung volume)

Fitness

Genetics

Node of exercise

Question 25

Assessment of VO2 max

Answer 25

Activate body’s large muscle groups
Incremental exercise test
Workload increases until exhaustion
expired air samples collected in last min of exercise and analysed for oxygen and carbon dioxide

Limitation: motivation

Question 26

What are the 3 systems that max oxygen consumption depend on?

Answer 26

Respiratory
Circulatory
Muscular

Question 27

Lactate threshold

Answer 27

Intensity of exercise at which lactate begins to accumulate in the blood at a faster rate than it can be removed

Question 28

What is the causes of BLA?

Answer 28

Low tissue oxygen 
Low blood oxygen 
Low blood flow to skeletal muscle 
Decreased redox potential 
Reliance on glycolysis 
Activation of fast twitch muscle fibres (type IIb)
Reduced lactate removal 
Imbalance between production and removal

Question 29

What are the symptoms of acute motion sickness?

Answer 29

Fatigue 
Nausea 
Decreased appetite 
Laboured breathing 
Tachycardia 
Nerve dysfunction

Question 30

Acute motion sickness

Answer 30

Increase ventilator drive due to decreased O2 causes respiratory alkalosis

Question 31

What is acclimitaztion?

Answer 31

Aim is to restore normal acid-base balance for adequate oxygenation

Question 32

What are the components of acclimitaztion?

Answer 32

Kidneys: excrete base HCO3- and conserve acid
Increased capillaries in tissue: reduced distance for oxygen diffusion
More mitochondria and oxidative enzymes: use oxygen more efficiently
Increased red blood cell production
Increased 2,3-BPG synthesis - increase oxygen unloading at tissues
Increased lung volume