34 Physiological adjustments to exercise

Question 1

what is VO2 max?

Answer 1

the maximum about of O2 that a person can consume during physical work, and is a measure of maximum cardiovascular function.

Question 2

T/F Ventilation is often the limiting factor for VO2?

Answer 2

False, this is almost never the case. The exception would be with someone with lung disease.

Question 3

what happens to cardiac output during exercise?

Answer 3

It will increase 5 fold!

However, if you are a trained athlete like me, it can increase up to 8 fold and put out 40L/min.

Question 4

What is the VO2 max equation?

Answer 4

VO2 max= CO(max) x (a-v)O2 difference (max)

Question 5

what is aerobic power?

Answer 5

aerobic power is a measure of the maximal amount of external physical work a person can perform over a given period.
(its VO2 represented in liters/min)

Question 6

what happens to blood lactate as you reach and exceed your VO2 max?

Answer 6

lactate levels shoot up dramatically because the body has to do more anaerobic respiration to keep up with the demands.

Question 7

If you have an athlete and a non-athlete who become injured and are bedridden for 4 weeks, which of the two will have a lower VO2 max?

Answer 7

Well, the person who started with the lower VO2 max which would be the non- athlete. However, the athlete would have a greater (percentage) reduction in VO2 max over the time period. Basically, the more you have, the more you loose in the same time frame.

Question 8

T/F The lower the initial level of max VO2, the greater the increase with training?

Answer 8

True

Question 9

what causes the increases in VO2 max in a child? an adult?

Answer 9

child (due to increases in SV and a-vO2 difference.

adult (only due to SV increases)

Question 10

What is the trend for VO2 max in life? at what age are you at your peak?

Answer 10

initially it increases until puberty, then falls. It once again increased during the late teens up to the age of 20. From 20 its all down hill.

Question 11

why do women generally have lower VO2 max values?

Answer 11

Because of lower hemoglobin.

Question 12

T/F Men and women have about the same VO2 max values before puberty?

Answer 12

True.

Question 13

what does the ATP-phosphocreatine system do?

Answer 13

It allows for quick energy by adding a phosphate to ADP. The enzyme is called creatine kinase (CK)
ADP + phosphocreatine—->creatine + ATP

Question 14

If I get up from my resting position, which energy method am I primarily using?

Answer 14

primarily the ATP-phosphocreatine system (<60 seconds)

Question 15

T/F PCr energy can be used directly for cellular work?

Answer 15

False, PCr has to first be added to ADP so that work can be done.

Question 16

How long does it take for PCr to become regenerated during rest?

Answer 16

about 3 minutes

Question 17

when breaking down glycogen and using it in glycolysis, how much energy do I get? How much energy from glucose?

Answer 17

Glycogen= 3 net ATP
Glucose= 2 net ATP

Question 18

How long can the glycogen pathway sustain my energy demands during exercise?

Answer 18

up to 2 minutes (other source notes say 1-5 min)

Question 19

what are some CONS about using glycolysis?

Answer 19

1) inefficient
2) buildup of lactic acid
3) lactic acid can impair further glycolysis and muscle contraction.

Question 20

what are some PROS about using glycolysis?

Answer 20

1) fast
2) anaerobic
3) allows for short term high energy exercise

Question 21

how much ATP will be generated using glucose through the oxidative system? Glycogen?

Answer 21

glucose=32 ATP

glycogen=33 ATP

Question 22

How many ATP are produced through the breakdown of palmitic acid?

Answer 22

106 ATP

Question 23

what is the major source of energy for oxidative phosphorylation?

Answer 23

triglycerides (one glycerol and 3 fatty acids)

Question 24

How does the body use the triacylglycerides?

Answer 24

triacylglycerides–>lipase–>glycerol and fatty acid–>mitochondria beta oxidation–> acetyl Coa—>Krebs cycle–>ETC

Question 25

What is the RER?

Answer 25

Respiratory Exchange Rate. It is a measure of gas exchange at the lung. RER=volume of CO2 produced / volume 02 uptake

Question 26

what does a RER of 1.0 mean? what about 0.7?

Answer 26

RER of 1.0 means the body is burning all carbs RER of .7 means the body is burning mostly fats (anywhere in between would be a mixture of the 2)

Question 27

above exercise intensities of 70% of maximum, what is the main source of energy?

Answer 27

Glucose

Question 28

What is the idea behind glycogen sparing with physical training?

Answer 28

It states that the better shape that you are in, the more that you will use fats, and your glycogen stores will be higher than in a non trained individual.

Question 29

which type of tissue in the body has the greatest capacity to increase its metabolic rate?

Answer 29

muscle tissue

Question 30

what innervates type 1 slow twitch muscle fibers? | what about type 2?

Answer 30

``` small A(alpha)2 motor neurons larger A(alpha)1 motor neurons ```

Question 31

Type I fibers are called what? Type IIa fibers are called what? Type IIx fibers are called what?

Answer 31

Slow oxidative fibers (SO) Fast oxidative glycolytic fibers(FOG) Fast glycolytic fibers (FG)

Question 32

what percent of muscle fibers are SO? FOG? FG?

Answer 32

SO---50% FOG---25% FG---25% (note that long distance runners would have more SO fibers while a body builder would have more FG fibers)

Question 33

what determines what percentage of SO, FOG, and FG fibers you have?

Answer 33

mainly genetics, but some training.

Question 34

What is the Henneman size principal?

Answer 34

It states that are you go to pick something up, you activate the type 1 fibers first, and if there isn't enough strength, then type 2 motor neurons are activated to move the object. Exception: high velocity activities

Question 35

In general, Type IIa fibers are intermediate between type I and type IIx muscle fibers. The exceptions are?

Answer 35

Type IIa: So these are not considered intermediates and are like the type IIx muscle fibers ``` Speed PC stores glycogen stores mysosin ATPase activity glycolytic enzyme activity ```

Question 36

How does muscle get bigger?

Answer 36

Through hypertrophy and not hyperplasia. Increase in sarcomeres predominantly in type II fibers.

Question 37

what does strength training do to muscle fibers as far as size?

Answer 37

strength training causes hypertrophy in both types, and that is about it. Note: lactate buffering capacity also increases with anaerobic exercise training.

Question 38

In general what does endurance training do for ST fibers and FT fibers?

Answer 38

The effects are the same for both all types! 1) increased oxidative capacity 2) increased glycogen content 3) increased fat oxidation 4) increased capillary density 5) increased mitochondria

Question 39

Strength gains in the initial six weeks of going to the gym are due to?

Answer 39

improved motor recruitment | suppression of self protective reflexes

Question 40

T/F endurance exercise does not enhance strength gains from resistance exercise, but resistance exercise does improve endurance exercise performance?

Answer 40

True