Ch 13: Physiology of Training

Question 1

What is the principal measurement associated with Aerobic Fitness?

Answer 1

VO2max

Question 2

Research indicates that the appropriate exercise stimulus to improve VO2max factors includes __________ ___________ (contract-relax cycle) using ________ _________ _________ particularly the legs, lasting ___ - ___ min, __ - __ per week @ __ - __% of VO2max

Answer 2

1.) Dynamic Exercise
2.) Large Muscle Groups/Mass
3.) 20-60min
4.) 3-5 per week
5.) 50-85%

Question 3

How long does the typical exercise study last?

Answer 3

As most research studies follow the school system, the typical exercise study program is about 8-12 weeks

Question 4

The average change in VO2 max during an exercise research study is about 15%. However, it can be as little as 2-3% or as high as 30-50% what 2 factors effect this change?

Answer 4

1.) Genetics; Some individuals may be high/low responders to training.

2.) Frequency and Magnitude of stress (Must be mindful of what the body can handle)

Question 5

What two adaptation factors directly explain an increase in VO2 max? Which factor is it more important to focus on in a study?

Answer 5

1.) Fick’s Equation factors (VO2max = Q x a-VO2diff)

2.) Bodyweight changes

It is more important to highlight the absolute changes of VO2 max which are the Fick equation variables

Question 6

Explain the tree of factors that affect SV.

Answer 6

Increased Plasma Volume, Fill time/venous return, and increased ventricular volume cause an increase in EDV.

Increased EDV, contractility, and peripheral resistance (afterload) cause a decrease in ESV

The adaptations described above all cause an overall increase in SV.

Question 7

What is the key difference between Cardiovascular and Muscular training in regards to adaptations from mode of training?

Answer 7

Cardiovascular adaptations are relatively similar regardless of training mode (Swimming vs. running vs. biking). However, muscular adaptations are only seen in the muscles recruited during a bout of exercise. (Bench vs. Squat).

Question 8

What factors in adaptation affect a-VO2 diff?

Answer 8

• Increased muscular blood flow due to decreased Sympathetic constriction of muscles
• Increased capillaries in working muscles to extract more oxygen
• Increased mitochondria to consume extracted oxygen

Question 9

Explain the capillary to fiber ratio and its importance to VO2max

Answer 9

The capillary to fiber ratio describes the capillary density of an adapted muscle. As gas exchange is a time dependent process, increased capillary density gives the traveling hemoglobin a higher chance of passing along oxygen/nutrients to the working muscle before the blood returns to the venous network.

Question 10

Is it more advantageous to have an increased number of mitochondria or to have fewer denser mitochondria? Why?

Answer 10

It is more advantageous to have larger, more dense mitochondria as it requires more resources to create new mitochondria as opposed to creating more folds and expanding already existing mitochondria.

Question 11

How does mitochondrial expansion benefit substrate system utilization?

Answer 11

More/Larger Mitochondria cause lower levels of ADP in proportion to mito meaning less stimulation of PFK allowing for preservation of CHO at lower intensities. Additionally, larger/more mitochondria allows for accommodation of glycolytic flux as well as increasing levels of lactate/pyruvate at higher intensities. This results in higher thresholds (LT and MLSS).

Question 12

Aerobically trained individuals tend to have a lower hematocrit. In what ways do the benefits outweigh the cons?

Answer 12

Although a lower hematocrit entails a lower proportion of RBC, increased venous return and stroke volume due to higher levels of plasma are enough to compensate.

Question 13

Increased Bicarbonate Buffer production is an adaptation in response to what during exercise?

Answer 13

Bicarbonate Buffer production increases in response to repeated disruption to pH homeostasis.

Question 14

How do Capillary and Mitochondrial expansion effect substrate utilization and preservation?

Answer 14

• Higher capillary density allows traveling blood to stay in the working muscle for longer periods therefore increasing fat uptake.
• Mitochondrial expansion causes increased levels of Carnitine Transferase which is the rate limiting enzyme of FFA utilization.
• Increased levels of FFA utilization allow for the preservation of plasma glucose and muscle glycogen.

Question 15

Describe the relationship between Aerobic training adaptations and the cross over concept.

Answer 15

As an individual goes through aerobic training adaptations (Capillary and Mitochondrial expansion), they become more efficient at using Fats as fuel. This causes the point at which substrate utilization changes to be at a higher intensity.

Question 16

For an untrained person when beginning to exercise what central adaptations can we see in 4 months of training?

Answer 16

An increase in their stroke volume and cardiac output.

Question 17

When an untrained person trains for a long period of time such as 32 months, what peripheral adaptations can we see?

Answer 17

An increase in their VO2 max and (A-VO2) Difference.

Question 18

True or false.
An elite athlete will have a heart rate max lower than the age-predicted equation for heart rate max.

Answer 18

True

Question 19

True or false.
As we begin to aerobic exercise, the venous return will rise.

Answer 19

True

Question 20

What is chronic Preload?

Answer 20

Bouts of aerobic exercise increases stretch on the myocardium. This occurs by being repeated over long term through dynamic exercise that creates an increase in myocardial sarcomeres in series. (Series add length together)

Question 21

What is an example of “Pressure Work”

Answer 21

High intensity exercise (ex. One rep max)

Question 22

What is Chronic Afterload?

Answer 22

Bouts of exercise with high afterload put high workload on the heart. Done repeatedly over long term results in an increase in myocardial sarcomeres in parallel. Making the heart thicker, more hypertrophy, and more forceful contractions.

Question 23

What can be a reason for chronic afterload if someone does not regularly train?

Answer 23

People with hypertension meaning elevated resting blood pressure.

Question 24

From rest to 40-50% of your VO2 max what muscle fibers are you most likely using?

Answer 24

Slow oxidative Fibers (Type I)

Question 25

From 50%-70% of your VO2 max what muscle fibers will be most dominant?

Answer 25

Fast oxidative glycolytic fibers (Type IIa)

Question 26

From 75%-100% of your VO2 max what muscle fibers will be most dominant?

Answer 26

Fast glycolytic fibers (Type IIx)

Question 27

What chronic training adaptation allows for more efficient offloading?

Answer 27

Increased capillary density

Question 28

To increase oxidative capacity of the mitochondria what must happen?

Answer 28

The expansion of the inter-mitochondrial membrane

Question 29

What are considered the more adaptable fibers?

Answer 29

Type IIa and Type IIx

Question 30

If someone were to aerobically train for 12 weeks where they’re running 65% of VO2 max or higher 3-4 days. What can we say about their muscle fiber and mitochondria?

Answer 30

Muscle fiber will not significantly change, however the mitochondria will grow in size in all three fibers.

Question 31

Relating to detraining, from days 1-12 we see a decrease in SV max, Q max, and VO2 max. What could be the reason?

Answer 31

A decrease in plasma volumes (This is the first adaptation we gain and lose).

Question 32

What are some results of detraining long term?

Answer 32

• Further decline in VO2

Question 33

If a trained person and an untrained person are both running at 5mph, explain why or why not the trained individual is at less relative working VO2.

Answer 33

Because specific workloads require set amounts of O2, whether the individual is trained or untrained they will be at the same working VO2.

Question 34

When comparing the same workload from a trained and untrained individual explain how and why RER would be different.

Answer 34

In the trained individual, RER would most likely be lower since the given workload is a lower percentage of their VO2 max compared to the untrained individual.