Acute Responses

Question 1

Acute response definition

Answer 1

Immediate short term responses that last for the duration of the activity and recovery process.

Question 2

Purpose of cardio-respiratory responses

Answer 2

To deliver more oxygen quickly and efficiently to the working muscles to produce aerobic energy for more muscular contractions.

Question 3

Cardiovascular Responses:
Increased Heart rate (HR)

Answer 3

The number of times the heart contracts (bpm)

a trained athlete has a lower resting HR
Max. HR - 220 - age

Question 4

Cardiovascular Responses:
Increased Stroke Volume (SV)

Answer 4

The amount of blood pumped out of the heart’s LV per beat (ml/beat)

SV increases during exercise, however, plateus when exercise intensities reach 40-60% of maximal capacity.

Question 5

Why does SV plateu?

Answer 5

• LV has a finite capacity and cannot fill any further.
• has less time to fill between contractions.

Question 6

Cardiovascular Responses:
Increases Cardiac Output (CO)

Answer 6

The amount of blood pumped out of the LV per minute (L/min)

CO = HR x SV

Question 7

Trained Athlete vs Untrained

Answer 7

At sub-maximal intensities:
Trained Athlete - lower HR
Untrained Athlete - higher HR

Maximal Intensity:
Trained Athlete - max HR, higher SV
Untrained Athlete - max HR, lower SV

Question 8

Cardiovascular Responses:
Increased Blood Pressure

Answer 8

A measure of the pressure of blood being pumped into the arteries.

BP = Systolic/Diastolic
systolic has the most change during exercise, whereas diastolic has minimal change.

Systolic - the pressure as the LV ejects blood into the aorta during heart contraction
Diastolic - the pressure in the arteries during relaxation of the heart.

Question 9

Cardiovascular Responses:
Increased Blood Flow

Answer 9

During exercise blood flow to working muscles increases via vasodilation (blood vessels widen), while blood flow to vital organs is decreased via vasoconstriction (blood vessels narrow).

During rest BF to vital organs is increased via vasodilation (blood vessels widen), while BF to working muscles is decreased via vasoconstriction (blood vessels narrow).

• includes Vasoconstriction (narrowing of blood vessels) and vasodilation (widening of blood vessels)

Question 10

Define vasodilation

Answer 10

Blood vessels dilate/widen to increase blood flow

Question 11

Define vasoconstriction

Answer 11

Blood vessels become narrower to reduce blood flow.

Question 12

Cardiovascular Responses:
Increased A-VO2 Difference

Answer 12

The difference in O2 concentration between arterial and venous blood.
[ml/per 100ml of blood]

Working muscles extract more of the available O2 from the blood via myoglobin to deliver more O2 to mitochondria for energy production for muscular contractions.

Question 13

Cardiovascular Responses:
Decreased Blood Plasma Volume

Question 14

Respiratory Responses:
Increased Respiratory Rate (RR)

Answer 14

Number of breaths taken per min
[breaths/min]

Question 15

Respiratory Responses:
Increased Tidal Volume (TV)

Answer 15

Air breathed in and out in one breath.
[L/breath]

Question 16

Respiratory Responses:
Increased ventilation (V)

Answer 16

Air breathed in and out in 1 min
[L/min]

V = RR x TV

Question 17

Respiratory Responses:
Increased Lung Diffusion

Answer 17

• O2 moves from an area of HIGH concentration in the alveoli to an area of LOW concentration in the capillaries.
• CO2 diffuses from the blood in the capillaries into the alveoli, moving from an area of high concentration to low concentration.

Question 18

Respiratory Responses:
Increased oxygen uptake

Answer 18

Amount of O2 taken up + used by the body to produce energy.

Question 19

VO2 Max

Answer 19

The maximum amount of O2 a person can bring in via the respiratory system, transport via the cardiovascular, and then utilise via the muscular system.

Question 20

Oxygen Deficit

Answer 20

Refers to the difference in O2 supply and demand that is needed to meet energy requirements.

O2 supply does not meet O2 demand

Question 21

Steady State

Answer 21

O2 supply = O2 demand

• takes longer to reach steady state if intensity is higher

Question 22

EPOC

Answer 22

Excess post-exercise oxygen consumption

• Amount of O2 our body consumes following an exercise session.
• After exercise, our body has to return to its resting state or homeostasis.
  elevated heart rate assist with more O2 to be distributed to assist with the removal of metabolic by-products

Question 23

Muscular Responses:
Increased Muscle Fibre and motor unit recruitment

Answer 23

Increased motor unit recruitment takes place so that more muscle fibres are activated to contract for better force production.

• greater the force/effort required
• greater motor units required
• greater the number of muscle fibres activated.

Question 24

Muscular Responses:
Increased Muscle Temperature

Answer 24

Heat is a bi-product of aerobic energy production, therefore increased rate of energy production, increases muscle temperature.

Question 25

What does increased muscle temp. do to the muscles?

Answer 25

Increased muscle temp. also increases muscle elasticity and muscle flexibility which reduces the risk of injury

• when ur body temp reaches abnormally high, your body sweats excessively in order to regulate body and muscle temp, leading to fatigue.

Question 26

decreased muscle substrate levels

Answer 26

• during exercise, muscular stores of ATP, creatine phosphate, glycogen and triglycerides begin to deplete as they are used to provide energy (act as fuel stores for atp production)
• the depletion of these energy stores contribute to the fatigue experienced

Question 27

increased muscle enzyme activity

Answer 27

• enzyme activity increases during exercise to produce the increased amounts of ATP required by the muscles. Enzymes are involved in all the chemical processes that produce energy through the 3 energy pathways
• myoglobin (enzyme) takes 02 from the blood to the mitochondria which produces more energy to allow for more muscular contractions

Question 28

Thermoregulation

Answer 28

vasoconstriction and vasodilation involved.