Exercise Phys

Question 1

What is the principle of adaptation and overload?

Answer 1

The body will respond to an excessive stimulus that is beyond the normal capacity of the body and eventually be able to increase its ability to respond to the stimulus (adaptation). If the stimulus exceeds the body’s ability to respond too much, injury can occur (overload).

Question 2

What is specific adaptation?

Answer 2

The body responds better to a particular stimulus during exercise. Meaning, the body systems must be trained similarly to the sport or activity. Ex: to improve as a swimmer, you should swim. To improve in football, you should train with anaerobic workouts.

Question 3

State the Fick equation for VO2 measurement.

Answer 3

VO2 = CO x (a-vO2)
VO2 = SV x HR x (a-vO2)

The rate of O2 being consumed by tissues (VO2) equals the cardiac output (CO = SV x HR) multiplied by the difference in arterial and venous O2 (a-vO2).

Question 4

What does endurance depend on?

Answer 4

Oxygen Transport System

Question 5

What effect does resistance training have on the heart and then endurance training. State the mechanisms.

Answer 5

Resistance training: heart muscle hypertrophy ( mainly LV) due to increased blood pressure that the heart has to pump against (afterload).

Endurance Training: heart fills more during diastole due to increased blood volume that occurs with endurance training (increased preload).

Overall Endurance trained leads to more hypertrophy.

Question 6

How does exercise lead to increased stroke volume?

Answer 6

Trained athletes develop a slower resting HR due to parasympathetic activity. The slower rate allows more time in diastole increasing the filling time and stretching the heart muscle. This allows a stronger contraction during systole and ejects more blood.

Question 7

What 3 factors affect stroke volume?

Answer 7

Venous return volume, heart contractility, aortic or pulmonary blood pressure

Question 8

What is a healthy ejection fraction?

Answer 8

50-65%

EF = SV/EDV

Question 9

What is the equation for estimating maximum HR?

Answer 9

208 - (0.7 x age) = MHR

Question 10

What is the purpose of increasing CO during exercise?

Answer 10

Meet the demands of tissue oxygen needs (mainly skeletal muscle)

Question 11

What blood pressure changes occur in the body in response to exercise?

Answer 11

Systolic Increases, Diastolic remains constant

Upper body exercise increase bp more due to smaller vessels and muscles leading to more resistance

Question 12

What is the change in blood volume that occurs in exercise?

Answer 12

Increase in plasma volume which decreases the viscosity of the blood allowing for better circulation.

Question 13

Best indicator of cardiorespiratory endurance.

Answer 13

VO2max

Question 14

How does the valsalva maneuver affect the cardiorespiratory system?

Answer 14

It traps air in the lungs restricting venous return and lowering cardiac output.

Question 15

What is the respiratory quotient (RQ)?

Answer 15

CO2 expired/oxygen consumed. Can indicate the main fuel source used by the patient.

0. 7 = fatty acids
1. 0 = CHOs

Question 16

What changes occur to VO2max, respiratory exchange ratio, and lactate threshold in a trained athlete?

Answer 16

LT: increases allowing better oxygen consumption with higher intensity exercise without raising lactate levels too much.

RER: decreases at rest meaning that fatty acids are the primary energy source

VO2max: increases but varies on individual

Question 17

How does aquatic training reduce stress on the CV system?

Answer 17

Submersion applies pressure all over the body which decreases venous pooling and improves venous return. Muscle blood flow doubles. Cardiac volume and stroke volume increase. HR decreases. CO increases.