Chapter 17 (Metabolism and Exercise)

Question 1

Short term changes to circulatory and respiratory system when exercising?

Answer 1

Respiratory system:
Heart rate increases
Vasodilation of arterioles in skeletal muscles
Increased blood flow to active muscles
Increased stroke volume
Reduced blood flow to digestive system
Vasodilation to arterioles supplying surface of skin

Circulatory system:
Increased breathing rate
Increased depth of breathing
Increased stroke volume

Question 2

What are short term consequences of exercise - Definition

Answer 2

Changes which occur during the period of activity.

Question 3

What are long term consequences of exercise?

Answer 3

Changes which occur as a result of the body adapting as a result of regular training?

Question 4

Government recommendations for exercise?

Answer 4

16-64 year old should be active every day.

150 minutes moderate intensity activity in 10 minutes or more bouts.
eg, 30mins exercise 5 times week
or 75 minutes vigorous activity across wee.
Strength training on at least 2 days per week.

Question 5

Why does heart rate increase during exercise?

Answer 5

caused by incr. in adrenaline secretion

incr. in stimulation of the sympathetic NS
incr. anticipatory response –> release of NT (e.g. adrenaline and noradrenaline)

HR increases proportional to exercise until plateau/max h.r. reached

Question 6

Why does vasodilation of arterioles in skeletal muscles occur during exercise?

Answer 6

secretion of nitric oxide by arteriolar endothelium

in response to fall in O(2) levels

Question 7

Ways of enhancing athletic performance?

Answer 7

Carbohydrate loading
RhEPO
Blood doping
Steroid enhancement

Question 8

Why does stroke volume increase with exercise?

Answer 8

more blood returns to left atrium

∴ larger volume of blood filling ventricle in diastole

∴ greater volume of blood pumped out in systole

Question 9

Why does breathing rate and tidal volume increase with exercise?

Answer 9

more air into alveoli –> incr. in concentration gradient ∴ O(2) can diffuse into the blood more easily

∴ incr. rate of aerobic respiration ∴ more CO(2) produced ∴ more H(2)CO(3) produced

incr. in blood acidity detected by chemoreceptors - sends impulses to respiratory centre in medulla
incr. in rate and extent of contractions of diaphragm and intercostal muscles

Question 10

Why does blood flow to the

Answer 10

Finish the short term changes

Question 11

What are the long term effects of exercise?

Answer 11

Circulatory:
Respiratory:
Skeletal:

Question 12

Definition of aerobic respiration?

Answer 12

A measure of the ability of the heart and lungs to respond to the demands of aerobic exercise.

Question 13

What are the three indicators of aerobic respiration?

Answer 13

efficiency of GES/CVS

extent of aerobic respiration without fatigue

efficiency of respiration

Question 14

How is aerobic fitness achieved?

Answer 14

20 mins of exercise

3 x per week

increasing in intensity to 50-55% of VO2 max
or 70% of MAX HR (220-age)

Question 15

Factors which affect aerobic respiration?

Answer 15

age

gender

smoking

malnutrition

motivation

programme

alcohol consumption

stimulants

depression

Question 16

give four health benefits of regular aerobic exercise

Answer 16

strengthened skeletal muscle

improved circulatory efficiency

reduced blood pressure

improved mental health

reduced risk of diabetes

stimulate bone growth

Question 17

How can aerobic exercise be improved?

Answer 17

(FITT)
increase:
- Frequency
- Intensity
- Type
- Time (i.e. duration)

Question 18

how is aerobic fitness measured?

Answer 18

decr. resting h.r.
decr. recovery time
incr. VO2 max

Question 19

how does a successful training programme bring improved aerobic fitness?

Answer 19

successful training will act as a stressor

body adapts by undergoing physiological and biochemical changes.

progressive overload –> prevents plateau

Question 20

Definition of VO2 Max?

Answer 20

Maximum rate at which oxygen can be taken in, absorbed, transported and used as measured during incremental exercise.

Question 21

safety consideration!!!

Answer 21

Prior to any investigation, consent needs to be given.
Check participants for:
asthma
heart conditions
pregnancy
high blood pressure
Participants also need to have had appropriate equipment training.

Question 22

How to measure success of a training programme?

Answer 22

Changes in HR (decrease)
Changes in recovery time (shorter)
Changes in VO2 mac (larger)

Question 23

What are physiological changes that could occur?

Answer 23

Normal cells
hypertrophy (cells have enlarged)
hyperplasia (more cells)

Question 24

Biochemical changes that could occur?

Answer 24

Inc. in myoglobin
Inc. in actin
Inc. in myosin.
(all intracellular proteins)

Question 25

What units is VO2 max measured

Answer 25

absolute rate = dm^3 min-1 O2 consumed

relative rate = ml kg-1 min-1
O2 consumed