Exercise Physiology

Question 1

Short term effect of cardiovascular system during exercise

Answer 1

-increase cardiac output through increased heart rate and stroke volume
-re-distribution of blood flow
-splenic contraction

Question 2

Splenic contraction during exercise

Answer 2

-smooth muscle in spleen contracts to release RBCs held in spleen at resting state and released into general circulation so there are more RBCs to carry oxygen

Question 3

Short term effects on the respiratory system during exercise

Answer 3

-increased respiration rate
-increased tidal volume
-increased minute ventilation
-increased efficiency of diffusion of oxygen and carbon dioxide

Question 4

Cardiac output

Answer 4

Amount of blood the heart pumps out in a unit time (e.g. minute)

Question 5

Stroke volume

Answer 5

Amount of blood pumped up of the left ventricle in one contraction

Question 6

How is cardiac output calculated?

Answer 6

Cardiac output = Heart rate x Stroke volume
CO = HR x SV

Question 7

Heart rate and stoke volume during exercise

Answer 7

Both increase

Question 8

Cardiac output in trained and untrained subjects

Answer 8

Cardiac output increases simlairly in trained and untrained subjects

Question 9

Cardiac output in untrained subjects

Answer 9

The increase in cardiac output is achieved mainly by a significant increase in heart rate and a moderate increase in stroke volume (SV)

Question 10

Cardiac output in trained subject

Answer 10

The increase is due to a significant increase in stroke volume and heart rate (HR)

Question 11

Redistribution of blood flow

Answer 11

In resting state - blood goes to gut, kidneys etc.
Whereas when exercising, blood is shunted away from the internal organs and towards the skeletal muscle so more O2 for movement

Question 12

Splenic reserve

Answer 12

-reserve of RBCs held within spleen
-10-20% RBC volume stored in spleen
-smooth muscle contracts to released this during exercise

Question 13

How is spleen adapted for good blood supply during exercise?

Answer 13

-spleen well vascularised
-lots of blood vessels and sinuses where RBCs reside
-when exercise begins the smooth muscle that lines the vessels and sinuses contract to squeeze all RBCs out into circulation through the splenic artery and veins
-increase in cell volume and ability to move O2 around the body to skeletal muscle and take waste products away

Question 14

Name arteries and veins 1-3 of spleen

Answer 14

1.splenic artery and vein
2.short gastric arteries and veins
3.left gastroepiploic artery and vein

Question 15

What happens when respiration rate increases?

Answer 15

-shifts more O2 and CO2
-blood ph decreased
-which is detected by chemoreceptors
-inspiratory area in medulla signals to diaphragm to contract more forcefully, CO2 exhaled, pH increases

Question 16

Bohr effect curves diagram

Answer 16

Question 17

Bohr effect

Answer 17

-increased amount of CO2 released from cells during aerobic respiration transported to blood
-means pH decreases - more CO2
-curve shifts to right
-affinity of Hb for O2 is much lower
-oxygen more readily released to the tissues and more for aerobic respiration

Question 18

Where are chemoreceptors to detect change in blood pH found?

Answer 18

-centrally in medulla oblongata
-peripherally in aortic and carotid bodies

Question 19

CO2 removal in body tissue diagram

Answer 19

Question 20

CO2 moving into lung tissues to be expired diagram

Answer 20

Question 21

Tidal volume

Answer 21

Amount of air that moves in and out of lungs with one complete respiratory cycle

Question 22

Vital capacity

Answer 22

Max amount of air that an animal can expel from lungs on max inhalation
-sum of inspiratory reserve volume, tidal volume and expiratory reserve volume
-relates to how much O2 and CO2 we can actually pass through the lungs to support aerobic respiration during exercise

Question 24

Residual volume

Answer 24

Amount of air that remains in the lungs after exhalation

Question 25

Inspiratory and expiratory diagram

Answer 25

Question 26

Main muscles of respiration

Answer 26

Intercostals and diaphragm

Question 27

Muscles groups that aid respiration during exercise

Answer 27

-pectorals -latissimus dorsi -external abdominal obliques

Question 28

Pectorals and latissimus dorsi role in respiration

Answer 28

Act on ribs to help move ribs and aid process of respiration

Question 29

External abdominal oblique involvement in respiration

Answer 29

Originate from part of ribcage and insert on abdomen -help move ribs to aid breathing and drawing air into lungs

Question 30

Long term effects of exercise

Answer 30

-decreased resting heart rate -decreased blood pressure -increased tidal volume -increased vital capacity -increased capilarisation - more O2 to tissues and more waste products taken away -hypertrophy of myocardium -increased aerobic capacity -faster recovery

Question 31

What is having thicker myocardium associated with?

Answer 31

With being trained and good at exercise

Question 32

What is having a bigger heart overall associated with?

Answer 32

Disease -depending on how much of chest the heart takes up

Question 33

What does the heart on the right show?

Answer 33

Left ventricular hypertrophy

Question 34

How does a trained individual have a faster return to normal heart rate and lower heart rate in general?

Answer 34

Because if increase stroke volume by pumping more blood out of left ventricle each minute - don’t need to have higher heart rate to achieve same cardiac output

Question 35

Aerobic capacity of trained subject

Answer 35

-max oxygen uptake (VO2max) -increased ability for heart to pump oxygenated blood around the body -ability for respiration within muscle cells —> more mitochondria and mitochondrial enzymes (Krebs cycle, ATP production) -means more mitochondria in skeletal muscle of trained subject

Question 36

Effect of exercise on other systems

Answer 36

-increase bone density - bone remodelling -muscle hypertrophy - muscle fibres types -increased insulin sensitivity -reduced cortisol - better well-being