Excercise & thermoregulation

Question 1

core temperature

Answer 1

37C (outer environment thermoneutral range is 21-30C)

Question 2

Heat exchange mechanisms

Answer 2

conduction
convection
radiation
evaporation(loss)
metabolism(gain)

Question 3

ATP production mechanisms

Answer 3

1. atp phosphorylation by vcreatine phosphate
2. anaerobic glycolysis
3. oxidative phsophorylation
4. fatty acid(lipid) oxidation

Question 4

ATP phosphorylation by creatine phosphate

Answer 4

• rapid, lasts ~10s
• 1atp per creatine phosphate molecule
  CP+ ADP = C + ATP

Question 5

Anaerobic glycolysis

Answer 5

• rapid but inefficient, goes 10sec ~ 2mins
• 2atp per glucose
  glucose –> pyruvate –> 2atp + lactic acid

Question 5

Oxidative phosphorylation

Answer 5

• slow but efficient, minutes to hours
• 36 atp per glucose
  glucose –> pyruvate –> 36ATP

Question 6

Fatty acid (lipid) oxidation

Answer 6

• slowest, most efficient, many hours
• 100+ ATP per FFA

Question 7

Ventilation changes due to excercise and causes

Answer 7

changes;
- more ventilation
- less venous O2
- more venous CO2
- less arterial CO2

Causes:
- greater core temperature
- greater arterial [H+] (acidic)
- plasma [adrenaline] & [H+] increase
- skeletal muscle feedback
- generation and propagation of motor commands

Question 8

cardiac changes due to exercise

Answer 8

increased cardiac output;
- incresed heart rate (~60 to 220-age)
- increased stroke volume(resting ~20mL)

blood flow redistribution
blood pressure changes(positive feedback)
baroreceptor reflex modification

Question 9

muscle fiber types

Answer 9

Type IIx
- fast glycolytic, quick acting with not a great oxygen supply/sotroage.

Type IIa
- fast oxidative glycolytic
- middle

Type I
- slow oxidative, good oxygen availability(many mitochondria, dense capillaries)

Question 10

Baroreceptive response pathway, and overriding.