Exercise Physiology: Ch. 9 - Circulatory Responses to Exercise(Mine)

The circulatory system works with the _______ system. Either ___________ system or __________ system

pulmonary; cardiopulmonary, cardiorespiratory

What are the three characteristics of blood?

plasma, cells, hematocrit

Purposes of the cardiorespiratory system include:
Transport ___ and _______ to tissues
Removal of ___ wastes from tissues
Regulation of ____ ________

O2, nutrients; CO2; body temperature

Plasma is the ______ portion of blood that contains _______, __________, and ________.

liquid; ions, proteins, hormones

Two major adjustments of blood flow during exercise include increase _____ ________ and redistribution of _____ ______ from inactive organs to active muscle.

cardiac output, blood flow

What are the three types of cells?

RBC, WBC, Platelets

Heart creates _____ to pump blood

pressure

Red blood cells contain ___________ to carry oxygen

hemoglobin

Arteries and arterioles carry blood _____ from heart

away

White blood cells are important in preventing _________

infection

Capillaries exchange of ____, ____, and _______ with tissues

O2, CO2, nutrients

Platelets are important in blood __________

clotting

Veins and venules carry blood ______ heart

toward

Hematocrit is the percentage of blood composed of ________

cells

Pulmonary circuit is located on the _____ side of the heart

right

Blood flow is directly proportional to ______ difference between the two ends of the system. Inversely proportional to ___________

pressure; resistance

Pulmonary circuit pumps __________ blood to the lungs via pulmonary arteries

deoxygenated

Pressure is proportional to the difference between ___ and ____ arterial pressure

MAP, right

Pulmonary circuit returns _______ blood to the left side of the heart via pulmonary veins

oxygenated

Hemodynamics
Resistance depends upon _______ of the vessel, _______ of the blood, and ________ of the vessel (greatest influence of resistance)

length, viscosity, radius

Systemic circuit is located on the ______ side of the heart

left

Resistance = ?

Resistance = (Length x velocity) / radius^4

Systemic circuit pumps _________ blood to the whole body via arteries

oxygenated

Sources of vascular resistance include MAP decrease throughout the _________ circulation. Largest BP drop occurs across the _________.

systemic, arterioles (arterioles are called "resistance vessels")

Systemic circuit returns __________ blood to the right side of the heart via veins

deoxygenated

Oxygen demand by muscles during exercise is ___-___x greater than at rest

15-25x

The heart wall contains what three layers?

Epicardium (outer protective layer), Myocardium (cardiac muscle), Endocardium (inner membrane encloses to keep blood in control)

Increased O2 delivery is accomplished by increased _______ _________, and redistribution of ______ ________ from inactive organs to working skeletal muscle .

cardiac output, blood flow

Cardiac output increases due to increased _____ ______ and ______ ________

heart rate and stroke volume

Myocardium receives blood supply via ______ arteries. High demand for ______ and _______

coronary; oxygen, nutrients

Myocardial infarction (MI)- blockage in coronary blood flow results in _____ damage

cell

Increased HR:
for adults: Max HR = ?

Max HR= 220-age (years)

Systole is the ______ phase. ________ of blood

contraction, ejection

increased HR:
for children: Max HR = ?

Max HR= 208-0.7 x age (years)

How much blood is ejected from ventricles per beat?

2/3

Increased SV- increases and then plateau at ___-___% VO2 max? No plateau in highly trained subjects

40-60%

Diastole is the _______ phase. ______ with blood

relaxation, filling

Arteriovenous difference is the amount of ___ that is taken up from 100 mL of blood

O2

At rest, which is longer, diastole or systole?

diastole

Arteriovenous difference increases during exercise due to higher O2 uptake in _______. Used for _______ ATP production.

tissues, oxidative

During exercise, which is shorter, systole or diastole?

both- are heart is beating faster

Fick equation is the relationship between what three things?

cardiac output (Q), Arteriovenous difference (a-vO2 difference), and VO2

Fick equation

VO2 = CO x a-vO2 difference

The heart has a two-step pumping action:
Right and left atria contract together emptying blood into the _______
Ventricles contract approximately ____ seconds after atrial contraction

ventricles, 0.1 seconds

Total cardiac cycle is ___ seconds at rest
___ seconds in diastole
___ seconds in systole

0.8 seconds; 0.5, 0.3

Redistribution of Blood Flow During Exercise
Increased blood flow to working skeletal muscle. At rest, ___-___% of cardiac output to muscle. Increases to ___-___% during maximal exercise.

15-20%; 80-85%

During diastole, pressure in ventricles is ____
Filling with blood from atria- ___ valves open when
ventricular P< atrial P

low; AV valves

Decreased blood flow to less active organs like which three?

liver, kidneys, GI tract

During systole, pressure in ventricles ______
Blood ejected in pulmonary and systemic circulation: _________ valves open when
ventricular P> aortic P

rises; semilunar valves

Redistribution depends on ________ rate, exercise intensity.

metabolic rate

Heart sounds: first sound is the closing of _____ valves. The second sound is the closing of ______ and ______ valves

AV valves, aortic and pulmonary valves

Regulation of local blood flow during exercise uses skeletal muscle _________ and __________ to visceral organs and inactive tissues.

vasodilation, vasoconstriction

Systolic pressure is pressure generated during _______ contraction

ventricular

Skeletal muscle vasodilation uses ____________

autoregulation

Diastolic pressure is pressure in the _______ during cardiac relaxation

arteries

Autoregulation causes blood flow to increase to meet ______ demands of tissues. This is due to changes what 6 things?

metabolic; O2 tension, CO2 tension, nitric oxide, potassium, adenosine, and pH

Pulse pressure is the difference between ______ and _______

systolic and diastolic

Changes in HR and BP depend on what?

type, intensity, and duration of exercise; environmental condition

Mean Arterial Pressure (MAP)

MAP= DBP + 0.33 (SBP-DBP)

_________ HR and BP in emotionally charged environment due to increases in _____ activity.

elevated, SNS

Hypertension is when blood pressure is above what?

140/90 mmHg

Emotional influence- can increase ____-_________ HR and BP. Does not increase peak HR and BP ________ exercise.

pre-exercise, during

Primary (essential) hypertension- causes are unknown (multifactorial); ___% of cases of hypertension

90%

At onset of exercise, rapid increase in ____, ___, ______ _______. Plateau in _______ (below lactate threshold) exercise.

HR, SV, cardiac output; submaximal

_________ hypertension is a result of some other disease processes

Secondary

During recovery, _______ in HR, SV, and cardiac output toward resting levels. This depends on _____ and _____ of exercise and _____ state of subject.

decrease; intensity and duration; training

Hypertension leaves a risk factor for what 4 things?

Left ventricle hypertrophy, atherosclerosis and heart attack, kidney damage, stroke

Incremental exercise- Heart rate and cardiac output increase _________ with increasing work rate. Reaches a plateau at ____% VO2 max.

linearly, 100%

What are the two determinants of mean arterial pressure (MAP)?

cardiac output, total vascular resistance

Blood pressure- mean arterial pressure increases ______. _______ BP increases and ________ BP remains fairly constant.

linearly; Systolic, diastolic

Factors that Influence Arterial Blood Pressure

short-term regulation and long-term regulation

Double product (rate-pressure product) increases linearly with exercise ________. Indicates the work of the heart.

intensity

Short-term regulation involves the ________ nervous system
Baroreceptors in _____ and _____ arteries
an increase in BP= _____ in SNS activity
a decrease in BP= _______ SNS activity

sympathetic; aorta, carotid arteries; decrease; increase

Double product = ?

Double product = HR x systolic BP

Long-term regulation involves the ________, via control of blood volume and renin-angiotensin-aldosterone system

kidneys

Arm vs. Legs Exercise
At the same oxygen uptake, arm work results in higher what? (2)

Heart rate, blood pressure

Contraction of the heart depends on electrical stimulation of the _______

myocardium

Higher HR due to higher _________ stimulation

sympathetic

Conduction system involves what four things?

Sinoartial node (SA node), atrioventricular node (AV node), Bundle Branches (left and right), Purkinje fibers

Higher blood pressure due to _____________ of large inactive muscle mass

vasoconstriction

Sinoartial node (SA node)

pacemaker, initiates depolarization

Intermittent Exercise-
Recovery of HR and BP between bouts depend on what three things?

fitness level, temperature and humidity, duration and intensity of exercise

Atrioventricular node (AV node) passes depolarization to ______. Brief delay allowing for ventricular filling

ventricles

Prolonged exercise-
____ ______ is maintained

cardiac output

Bundle Branches (left and right) connect _____ to left and right ventricle

atria

Prolonged exercise-
Gradual decrease in ____ _______ due to dehydration and reduced plasma volume.

stroke volume

Prolonged exercise-
Gradual increase in ______ ______ during prolonged exercise (particularly in heat); cardiovascular drift.

heart rate

Purkinje fibers spread wave of ________ throughout ventricles

depolarization

Electrocardiogram (ECG) records ________ activity of the heart

electrical

Sudden cardiac death during exercise is uncommon. __/______ youth athletes

1/200,000

P wave

artial depolarization

Sudden cardiac death during exercise is caused by abnormal, lethal heart rhythms and in children and adolescents, due to what 3 things?

Genetic abnormalities of coronary arteries, cardiomyopathy, myocarditis

QRS complex- __________ depolarization and ________ repolarization

ventricular, atrial

In adults, due to what 2 things?

coronary artery disease, cardiomyopathy

T wave- ________ repolarization

ventricular

Central Command Theory:
Initial signal to "drive" the _________ system comes from higher brain centers. Due to centrally generated motor signals.

cardiovascular

ECG abnormalities may indicate ______ ______ disease
ST-segment depression can indication _________ __________

coronary heart, myocardium ischemia

Central Command Theory:
Fine-tuned feedback from what 4 receptors?

heart mechanoreceptors, muscle chemoreceptors, muscle mechanoreceptors, baroreceptors

Atherosclerosis is when _____ ______ narrows coronary arteries and reduces blood flow to _______

fatty plaque, myocardium (myocardial ischemia)

Muscle chemoreceptors are sensitive to muscle _______ (K+, lactic acid). Exercise ______ reflex.

metabolites; pressor

Muscle mechanoreceptor sensitive to _____ and _____ of muscular movement.

force, speed

Regulation of Heart Rate
Parasympathetic nervous system- via ______ nerve. Slows heart rate by inhibiting ___ and ___ node

vagus; SA and AV node

Regulation of Heart Rate
Sympathetic nervous system- via _____ ________ nerves. Increases HR by stimulating ____ and ___ node

cardiac accelerator nerves, SA and AV node

Baroreceptors are sensitive to changes in ______ blood pressure

arterial

Regulation of Heart Rate
Low resting HR due to ____________ tone

parasympathetic tone

Regulation of Heart Rate
Increase in HR at onset of exercise. Initial increase due to __________ withdrawal. Later increase due to increased _____ stimulation

parasympathetic, SNS

Regulation of stroke volume
End-diastolic volume (EDV) is the volume of blood in the _________ at the end of diastole ("preload")

ventricles

Regulation of stroke volume
Average aortic blood pressure is the pressure the heart must pump against to ______ blood ("afterload"). Mean arterial pressure

eject

Regulation of stroke volume
Strength of the ventricular contraction (contractility) is enhanced by circulating _________ and _____________; and by direct ___________ stimulation of the heart

epinephrine and norepinephrine; sympathetic

End-Diastolic Volume
Frank-Starling mechanism says that greater EDV results in a more ______ contraction. This is due to the stretch of _______.

forceful, ventricles

End-Diastolic Volume is dependent on what?

venous return

Venous return is increased by _____________ via the SNS

vasoconstriction

Venous return is also increased by _________ __________ __________

skeletal muscle pump

Skeletal muscle pump is rhythmic skeletal muscle contractions force blood in the ________ toward the heart. One-way valves in veins prevent _______ of blood.

extremities, backflow

Venous return is also increased by _________ pump.

respiratory

Respiratory pump changes in ________ pressure pull blood toward heart

thoracic