Chapter 4 - Acute responses to exercise

Question 1

define acute physiological response to exercise?

Answer 1

am immediate response to exercise with the respiratory, cardiovascular and muscular systems that last for the duration of exercise and recovery

Question 2

what is ventilation? at rest versus during maximal exercise?

Answer 2

air breathed in and out per minute
rest = 6L/min
maximal = 192L/min

Question 3

how is ventilation calculated?

Answer 3

v = tidal volume x respiratory rate

Question 4

what happens to ventilation when exercise intensity increases?

Answer 4

ventilation increases, from the increase in RR and TV. At sub-max exercise ventilation increases rapidly at the start and then more slowly until it plateaus, can be 15-30 litres more than at resting levels

Question 5

what is tidal volume? at rest versus during maximal exercise?

Answer 5

amount of air inspired and expired per breath
rest = 0.5L
maximal = 4L

Question 6

what happens to tidal volume as exercise intensity increases?

Answer 6

it increases, however plateaus at high intensities.

Question 7

what is respiratory rate? at rest versus during maximal exercise?

Answer 7

breaths per minute
rest = 12
maximal = 48

Question 8

what is gas exchange?

Answer 8

the movement of gases in and out of the circulatory system, moving from high to low concentration

Question 9

what happens to gas exchange during exercise?

Answer 9

it increases so that greater amount of oxygen and carbon dioxide can be exchanged. this allows for greater amounts of oxygen to be available at the muscle and for greater amounts of carbon dioxide to be removed

Question 10

define oxygen uptake? during rest?

Answer 10

the ability to consume oxygen for energy consumption

rest = 0.3-0.4 L/min

Question 11

what is stroke volume? rest versus maximal intensity?

Answer 11

the amount of blood pumped out of the left ventricle of the heart per beat
rest = 75ml/beat
maximal = 112ml/beat

Question 12

what happens to stroke volume when exercise intensity increases?

Answer 12

it increases due to increased demand for oxygen at working muscles, however plateaus at sub-maximal intensities, left ventricle can’t pump out blood any faster

Question 13

what is heart rate?

Answer 13

beats per minute

Question 14

what happens to heart rate when exercise intensity increases?

Answer 14

increases until maximum heart rate is achieved

Question 15

what is cardiac output? rest versus maximal intensity?

Answer 15

litres of blood pumped out of left ventricle per minute
rest = 6.2l/min
maximal = 22.4l/min

Question 16

what happens to cardiac output when exercise intensity increases?

Answer 16

it increases due to increased heart rate and stroke volume

Question 17

what is systolic blood pressure?

Answer 17

represents the maximum pressure exerted in the arteries when the heart contracts, is the top figure

Question 18

what is diastolic blood pressure?

Answer 18

force by blood on arterial walls during ventricular relaxation, bottom figure

Question 19

what happens to blood plasma volume during exercise?

Answer 19

decreases

Question 20

what happens to the distribution of blood flow during exercise?

Answer 20

redirected away from organs towards working muscles

Question 21

what is a-vo2 difference?

Answer 21

the difference between oxygen concentration in the arteries vs the veins

Question 22

what happens to a-vo2 difference during exercise?

Answer 22

increases because a greater amount of oxygen being extracted by working muscles from the arteries leaving less in the veins

Question 23

how does vasodilation and vasoconstriction assist in redistribution of blood during exercise?

Answer 23

vasodilation allows for an increase of blood flow to working muscles, vasocontriction decreases the amount of blood going to non-essential areas

Question 24

what is motor unit recruitment?

Answer 24

during exercise the force of working muscles increases, during exercise more motor units are required to produce more force, the number of units recruited depends on the level of force required

Question 25

what happens to energy substrates during exercise?

Answer 25

they decrease: pc, glycogen, triglycerides, atp

Question 26

what happens to the production of metabolic by-products during exercise?

Answer 26

they increase

Question 27

what happens to body temp during exercise?

Answer 27

increases due to breaking down energy which produces heat as a by-product

Question 28

what is oxygen deficit?

Answer 28

The amount by which oxygen consumption does not meet oxygen demand. The lag in oxygen uptake before steady state is achieved.

Question 29

what is steady state?

Answer 29

oxygen demand = oxygen supply, only occurs at or below LIP (85% max HR)

Question 30

what is EPOC?

Answer 30

aka oxygen debt. EPOC mean the volume of oxygen consumed during recovery above ordinary resting level. The size of EPOC is proportional to the intensity and duration of the exercise.

Question 31

what are the two stages of EPOC?

Answer 31

Alactacid oxygen debt = restoration of PC stores

Lactacid oxygen debt= removal of accumulate LA

Question 32

what is aerobic capacity?

Answer 32

This is the ability of the body to utilise oxygen to perform work or exercise. Depends on the efficiency and development of the cardiovascular and respiratory systems

Question 33

what is vo2 max?

Answer 33

The maximum amount of oxygen being taken in, transported to and consumed by the working muscles to produce ATP. measured in ml/kg/min

Question 34

when do we reach our vo2 max?

Answer 34

body can’t increase the amount of oxygen it consumes and utilises, this is your VO2 max

Question 35

what causes ventilation to increase?

Answer 35

an increase in tidal volume and respiratory rate

Question 36

what are 2 factors that will affect an individuals vo2 max?

Answer 36

1. aerobic fitness: Vo2 max is determined by the heart circulatories ability to utilise oxygen
2. body size: heaver person have larger vo2 max consumption