EXSC 293: Chapter 8 Practice Questions

Which of the following best describes HR max? a. reached at ~40 to 50% b. achieved after all-out effort to volitional fatigue c. stimulated by the parasympathetic nervous system d. artificially lowered by high blood H+ content

Steady-state heart rate can be used to ____. a. determine tissue oxygen extraction b. estimate stroke volume during exercise c. predict aerobic capacity d. calculate anaerobic threshold

Which of the following is commonly used to estimate HR max? a. maximal cardiac output or maximal stroke volume b. 220 - age in years c. (220 x age in years)/0.7 d. the lactate threshold

Which of the following will decrease stroke volume? a. increased preload b. increased contractility c. increased Ca2+ concentrations d. increased afterload

The mechanism that underlies preload's effects on stroke volume is the ____. a. Frank-Starling mechanism b. Hering-Breuer mechanism c. Willis mechanism d. end-diastolic mechanism

Compared to untrained individuals, trained endurance athletes have ____. a. higher maximal heart rates b. higher resting cardiac outputs c. higher resting heart rates d. higher maximal stroke volumes

When neural and circulating norepinephrine lead to an increase in stroke volume, it is due to ____. a. increased preload b. increased contractility c. increased afterload d. increased resistance

If blood pressure is relatively low, will it have an effect on stroke volume? Why? a. no, because blood pressure has no effect on end-diastolic volume b. yes, because they are both indicators of good cardiovascular health c. yes, because the left ventricle pumps against less resistance d. no, because the vasculature does not affect cardiac function

Which of the following is not true about cardiac output? a. It decreases as difference increases. b. It increases linearly with exercise intensity. c. It is the primary limiting factor of . d. It is the product of stroke volume and heart rate.

Which one of these increases in direct proportion to exercise intensity? a. diastolic blood pressure b. venous oxygen content c. systolic blood pressure d. arterial oxygen content

Which of these systolic pressures would realistically be seen at maximal endurance exercise? a. 80 mmHg b. 120 mmHg c. 160 mmHg d. 200 mmHg

During endurance exercise, total peripheral resistance ____. a. increases greatly b. increases somewhat c. stays constant d. decreases

The rate-pressure product is an index of ____. a. myocardial metabolism b. vascular stiffness c. circulating catecholamines d. afterload

During moderate exercise in the heat, which vascular beds receive the most blood flow? a. muscle, splanchnic (gut) b. muscle, renal (kidneys) c. muscle, skin d. muscle, brain

Which type of blood vessel is primarily responsible for redirecting blood flow? a. arteries b. arterioles c. capillaries d. venules e. veins

During maximal exercise, how much cardiac output is redirected to muscles? a. 20% b. 40% c. 60% d. 80%

Accumulation of metabolic by-produces in muscle (H+, CO2, heat) leads to ____. a. vasoconstriction b. vasodilation c. sympathetic activation d. reduced muscle blood flow

Cardiovascular drift is associated with ____. a. increased muscle sympatholysis b. increased cardiac output c. decreased venous return d. decreased heart rate

Increased blood pressure during exercise has what effect on plasma volume? a. It increases due to increased capillary oncotic pressure. b. It decreases due to decreased capillary oncotic pressure. c. It decreases due to increased capillary hydrostatic pressure. d. It increases due to increased tissue oncotic pressure

If dehydration causes hematocrit to rise to 60% what is the consequence? a. enhanced exercise capacity due to higher red blood cell concentration b. enhanced exercise capacity due to lower blood viscosity c. diminished exercise capacity due to enhanced venous return d. diminished exercise capacity due to impeded blood flow

Ventilation is ___. a. directly proportional to exercise intensity b. inversely proportional to exercise intensity c. not related to exercise intensity d. primarily an anticipatory response to exercise

Which of the following does not contribute to ventilatory regulation during exercise? a. chemoreceptors in the brain, carotid bodies, and lungs b. baroreceptors in the carotid sinus c. chemoreceptors in muscles d. stretch receptors in the right atrium

Based on breathing patterns immediately after exercise, post-exercise breathing is most likely ____. a. perfectly matched to metabolic need b. determined by PO2 c. mediated solely by neural mechanisms d. regulated by blood pH, PCO2, and temperature

Why does hyperventilation decrease the drive to breathe? a. It decreases PCO2 and increases pH. b. It increases PCO2 and decreases pH. c. It increases PO2 and decreases pH. d. It decreases PO2.

If the ventilatory equivalent for oxygen starts to increase and at the same time the ventilatory equivalent for carbon dioxide does not increase, this means that ____. a. aerobic metabolism is increasing b. ventilation is becoming more efficient c. anaerobic metabolism is increasing d. ventilation is not meeting oxygen demands of the body

The lactate threshold is best estimated using ____. a. maximal voluntary ventilation b. anaerobic threshold c. EIAH d. venous PO2

During maximal exercise, respiratory muscles can receive up to what percentage of cardiac output? a. 2% b. 9% c. 11% d. 15%

Compared to other skeletal muscles, respiratory muscles ____. a. have a greater anaerobic capacity b. have fewer capillaries c. have a greater oxidative capacity d. have a greater ratio of type II to type I fibers

The most effective buffer in the body is ___. a. protein b. phosphate c. hemoglobin d. bicarbonate

Urine produced after strenuous exercise is most likely ___ compared to urine produced before exercise.

____, or the arterial resistance against which the ventricle must pump, is a determinant of stroke volume.

_____ averages 60 to 80 beats/min in normally active people but can be as low as 30 to 40 beats/min in endurance-trained athletes.

The mechanism by which the heart generates a stronger contraction when the ventricle is stretched more during diastole is called the ___.

During submaximal exercise at a constant workload, heart rate reaches a plateau called _____.

____ influences stroke volume based on the degree of stretch that end-diastolic volume places on the ventricle.

The ___ describes the relationship between metabolism and cardiovascular function, resulting in the equation = x difference.

____ is most accurately estimated using 208 - (0.7 x age in years).

When heart rate increases just prior to the start of exercise, this phenomenon is called a(n) _____.

After prolonged aerobic exercise in a hot environment, ____ occurs, where stroke volume gradually decreases and heart rate gradually increases.

The increase in the blood-cell-to-plasma ratio that can occur after excessive sweating is called _____.

______, or the pressure exerted by protein, is a critical determinant of fluid movement into and out of capillaries.

_____ is a direct index of tissue oxygen extraction from the blood.

____ is the pressure exerted by fluid inside capillaries; it is commonly simplified to blood pressure.

_____ = heart rate x systolic blood pressure and is an indirect index of myocardial oxygen demand.

The net systemic vascular resistance is also called _____.

When sympathetic vasoconstriction is blunted in exercising muscle, this is referred to as ____.

The theory of ____ helps explain why cardiovascular responses to exercise can be seen much earlier than would be expected based solely on tissue metabolite accumulation.

Resistance athletes often try to lift very heavy weights by exhaling forcefully while closing the glottis (i.e. "bearing down"), also known as a _____.

____ (or shortness of breath) is commonly experienced by out-of-shape individuals who try to exercise at excessively high intensities.

At low intensities, ventilation increases via increases in _____.

Maximal ventilation rates can range from ____ L/min (for smaller individuals) to ____ L/min (for larger individuals)

Ventilation (both depth and rate) that exceeds what is needed by the body at the moment is called ____.

The point at which ventilation increases disproportionally compared to oxygen consumption is called the ____.

The ____ is the point during exercise at which there is an increase in / without a concomitant increase in /.

The ____, expressed as /, is an important indicator of whether overall ventilation is well matched to the body's demand for oxygen.

The ratio of the volume of expired air to the volume of carbon dioxide produced is referred to as the ____.

____ is the body's maximal capacity to move air in and out of the lungs, which is significantly greater than the functional maximal ventilation that occurs during exercise.

____ occurs in elite endurance athletes when there is a mismatch between ventilation and perfusion, resulting in lower hemoglobin O2 saturation at high intensities.

Scientists are unsure what causes asthma symptoms to develop or worsen during exercise (a phenomenon also referred to as ______).

When the H+ concentration in the tissues or blood is too high, this is called ____.

T/F: Maximal heart rate is determined by age, not fitness status.

T/F: In most cases, stroke volume increases linearly up to .

T/F: Many scientists view cardiac output as the limiting factor for .

T/F: During endurance exercise, diastolic blood pressure increases proportionally with exercise intensity while systolic blood pressure may actually decrease a little.

T/F: The kidney and splanchnic circulations are deprived of normal blood flow during exercise.

T/F: The immediate increase in ventilation that occurs before the onset of exercise is stimulated by changes in blood CO2 and H+.

T/F: In the absence of blood tests, respiratory gas measurements can be used to approximate the lactate threshold.

T/F: Ventilation commonly limits performance by providing insufficient O2 intake and CO2 removal.

T/F: Exercise-induced arterial hypoxemia occurs in 40 to 50% of elite athletes exercising at near-maximal intensities.

T/F: Active recovery leads to additional acid production and should be avoided after exercise.

T/F: Chemical buffers in the blood are only a short-term solution for blood acidosis after exercise.