Final Exam

Which of the reasons below best explains why exercise typically does not lead to weight loss? a. Compensatory behaviors like eating more the rest of the day. b. The relatively small number of calories burned during a typical bout of exercise. c. The automation of our activities of daily living. d. All of the above e. None of the above - exercise does usually lead to weight loss

all of the above

Heat energy gets from the body core to the skin primarily via: a. Countercurrent heat exchange b. Evaporation c. Conduction d. Convection e. Radiation

convection

What term or abbreviation is described by the definition below? "The movement of heat by the circulation of fluid" a. Evaporation b. Radiation c. Conduction d. Convection

convection

With high-intensity resistance training, very old adults demonstrate relatively similar levels of hypertrophy compared with young adults. True False

True

What term or abbreviation is described by the definition below? The greatest rate of oxygen use by the body measured during severe dynamic exercise. a. VEmax b. HRmax c. SVmax d. VO2max e. VTmax

VO2max

If we exercise in a humid environment, which mode of heat dissipation would be most affected? a. Countercurrent heat exchange b. Convection c. Evaporation d. Radiation e. Conduction

evaporation

The most important mode of heat transfer from the body to the environment during exercise is what? a. Conduction b. Countercurrent heat exchange c. Evaporation d. Convection e. Radiation

evaporation

Of the choices listed below which is the first to action to occur in generating a muscle contraction? a. propagation of motor neuron action potential via t-tubules b. Ca2+ reuptake by sarcoplasmic reticulum c. binding of ATP to myosin d. binding of Ca2+ to tropomyosin

propagation of motor neuron action potential via t-tubules

The LDH isozyme that predominates in fast-twitch muscle favors the conversion of ________ to _______. a. acetyl-CoA, citrate b. lactate, pyruvate c. pyruvate, acetyl-CoA d. FFA, acetyl-CoA e. pyruvate, lactate

pyruvate, lactate

The central controller within the thermoregulatory pathway is: a. the medulla b. the hypothalamus c. the pons d. the NTS

the hypothalamus

When one initially arrives at altitude, the primary response is to hyperventilate. This helps minimize any decline in PaO2 by: a. shifting the oxyhemoglobin dissociation curve to the left. b. causing dehydration c. increasing PaO2 d. minimizing the fall in PAO2 e. increasing PvO2

?? Not a

What are the effector organs and tissues that the brain targets in order to regulate body temperature? a. Blood vessels, thirst mechanism, endocrine glands, sweat glands b. Blood vessels, sweat glands, endocrine glands, skeletal muscle c. Blood vessels, thirst mechanism, skeletal muscle, sweat glands d. Blood vessels, digestive tract, sweat glands, thirst mechanism

?? Not c

Endurance trained individuals have a lower VE during submaximal exercise. Which of the factors listed below is most likely to be a direct cause of the lower VE? a. Lower PACO2 b. Lower body temperature c. Higher body temperature d. Lower PaCO2 e. Higher PaO2

?? Not d

What is the most likely cause of the shift in the ventilatory threshold in endurance-trained individuals? a. Higher VO2max. b. The shift in the lactate threshold. c. Greater oxidative capacity of skeletal muscles. d. Greater VEmax

?? Not d

Why does exercising above one's lactate threshold limit endurance performance? a. The farther above the lactate threshold, the greater the reliance on fat metabolism, leading to a depletion of glycogen and muscle fatigue. b. The farther above the lactate threshold the greater the reliance on glycolysis. Therefore, there is a reduction in Kreb's cycle flux, reducing the resynthesis of oxaloacetate, resulting in reduced oxidative ATP production leading to muscle fatigue. c. As lactate production increases FFA availability declines. This accelerates glycogen utilization leading to glycogen depletion and reduced fat metabolism through Kreb's cycle. d. The farther above the lactate threshold, the less oxygen is available for aerobic metabolism, reducing oxidative metabolism of ATP resulting in muscle fatigue.

?? not b C?

What term or abbreviation is described by the definition below? The volume of gas that reaches the respiratory zone of the lungs. a. Arterial ventilation b. Minute ventilation c. Alveolar ventilation d. Respiratory ventilation e. Dead space ventilation

Alveolar ventilation

Individuals with obstructive sleep apnea can stop breathing during their sleep for more than a minute at a time. During this time their drive to breathe increases until they can create enough pressure to overcome the resistance to airflow caused by the obstruction. What is the primary input to the respiratory centers that causes the sleeping individual to increase their drive to breathe? a. A decrease in PACO2 b. An increase in PaCO2 c. An increase in PAO2 d. An increase in metabolism e. An increase in temperature

An increase in PaCO2

What term or abbreviation is described by the definition below? "A liquid changing to its gaseous state due to an increase in the temperature of the liquid" a. Evaporation b. Conduction c. Convection d. Radiation

Evaporation

Very old adult demonstrate the same absolute increase in muscular strength as younger adults. True False

F

When one exercises at altitude, how does their heart rate compare to when they perform the same activity at sea level? a. Heart rate is higher because the air is less dense at altitude, reducing PaO2, and thus requiring greater Qc in order to deliver adequate O2 to the tissues. b. Heart rate is lower because the reduced PaO2 is sensed by the arterial chemoreceptors, causing a slightly reduced heart rate in order to protect the myocardium from becoming ischemic. c. Heart rate is lower because the air is less dense at altitude, making it easier to move through the air, thus reducing total work being done. d. Heart rate is higher because the reduced PaCO2 is sensed by the central chemoreceptors, reducing efferent vagal outflow from the hypothalamus in order to minimize respiratory alkalosis.

Heart rate is higher because the air is less dense at altitude, reducing PaO2, and thus requiring greater Qc in order to deliver adequate O2 to the tissues

How does increased pulmonary ventilation reduce blood pH? a. It increases blood flow which increases the uptake of lactate by the liver. b. It decreases PaCO2 promoting the conversion of hydrogen ion to carbon dioxide. c. It promotes the conversion of pyruvate to Acetyl-CoA rather than lactate. d. It increases the amount of bicarbonate in the blood.

It decreases PaCO2 promoting the conversion of hydrogen ions to carbon dioxide

Which statement below best explains why the shift in metabollism that occurs while at altitude is advantageous? a. Both fat and carbohydrate metabolism increase because total metabolism is greater at altitude. b. Metabolism remains unchanged due to counter-regulation of increased lactate by respiratory acidosis. This favors unloading within tissue beds. c. Metabolism shifts toward greater utilization of carbohydrates because you get more ATP per liter of oxygen consumed with carbohydrate compared to fat. d. Metabolism shifts to greater fat utilization since you get more ATP per gram of fat compared to carbohydrate or protein.

Metabolism shifts toward greater utilization of carbohydrates because you get more ATP per liter of oxygen consumed with carbohydrate compared to fat

Which of the reasons below best explains how exercise can be used to prevent or manage diabetes? a. Exercise leads to weight loss, which improves insulin sensitivity. b. The stress of exercise leads to increased insulin production, which leads to greater glucose uptake by the tissues of the body. c. Muscle contraction stimulates the translocation of glucose transporter proteins, which facilitate diffusion of glucose through the cell membrane. d. The increased ATP use during exercise reduces intracellular glucose concentration. This increases the diffusion gradient, causing glucose to more rapidly diffuse into the muscle cell.

Muscle contraction stimulates the translocation of glucose transporter proteins, which facilitate diffusion of glucose through the cell membrane

Which energy pathway is used mainly to produce ATP during 5 seconds of all out exercise? a. ETC b. glycolysis c. Kreb's cycle d. PCr-ATP

PCr-ATP

Rank each one of the energy systems (glycolysis, PCr-ATP, Krebs/ETC) in order from fastest to slowest rate of ATP production. a. Krebs/ETC, PCr-ATP, glycolysis b. PCr-ATP, Krebs/ETC, glycolysis c. PCr-ATP, glycolysis, Krebs/ETC d. Gycolysis, Krebs/ETC, PCr-ATP e. Glycolysis, PCr-ATP, Krebs/ETC

PCr-ATP, glycolysis, Krebs/ETC

Rank each one of the energy systems (glycolysis, PCr-ATP, Krebs/ETC) in order from shortest duration to longest duration for which they can maximally produce ATP. a. PCr-ATP, glycolysis, Krebs/ETC b. Krebs/ETC, PCr-ATP, glycolysis c. PCr-ATP, Krebs/ETC, glycolysis d. Glycolysis, Krebs/ETC, PCr-ATP e. Glycolysis, PCr-ATP, Krebs/ETC

PCr-ATP, glycolysis, Krebs/ETC

What term or abbreviation is best described by the definition below? The partial pressure of oxygen in the arterial tree. a. PAO2 b. PbO2 c. PO2 d. PaO2

PaO2

Which of the individuals above would most likely show the greatest increase in maximal aerobic capacity after several months of endurance training? a. Person 1:70% Type I; 20% Type IIa; 10% Type IIx b. Person 2: 45% Type I; 10% Type IIa; 45% Type IIx c. Person 3: 33% Type I; 33% Type IIa; 33% Type IIx d. Person 4: 10% Type 1; 20% Type IIa; 70% Type IIx

Person 1: 70% Type I; 20% Type IIa; 10% Type IIx

Which of the following individuals would most likely show the greatest strength and muscle mass gains following several months of high resistance weight training? a. Person 1: 70% Type I; 20% Type IIa; 10% Type IIx b. Person 2: 45% Type I; 10% Type IIa; 45% Type IIx c. Person 3: 33% Type I; 33% Type IIa; 33% Type IIx d. Person 4: 10% Type I; 20% Type IIa; 70% Type IIx

Person 4: 10% Type I; 20% Type IIa; 70% Type IIx

Which term or abbreviation is described by the definition below? The amount of blood pumped out of the heart with each contraction of the left ventricle. a. Pulmonary capillary blood flow b. Stroke volume c. Cardiac output d. Blood volume e. Afterload

Stroke volume

When one trains at altitude, they typically have to train at lower absolute exercise intensities. Why? a. The absolute oxygen cost of the activity is greater at altitude compared to sea level. b. More blood flow is required for thermoregulation, so less is available for skeletal muscle. c. The oxygen cost of the activity represents a greater percentage of the individual's maximal oxygen consumption. d. Both choice 1 and 3

The oxygen cost of the activity represents a greater percentage of the individual's maximal oxygen consumption

What is the biggest danger of determining exercise intensity from age-predicted maximal heart rates? a. There is a large amount of variability in age-related maximal heart rate, so there is a strong possibility of over- or under-estimating maximal heart rate. b. Work efficiency changes between low and high-intensity exercise, so you may underestimate VO2max. c. There may be error in measuring heart rate. d. You can't ensure that VO2 levels-off.

There is a large amount of variability in age-related maximal heart rate, so there is a strong possibility of over- or under- estimating maximal heart rate

If you were going to participate in moderate-to-vigorous physical activity next August, would it be beneficial to become heat acclimatized before you participate in that activity? a. No, because heat acclimatization only lasts for 8 to 12 hours, so unless your last acclimatization session is within 8 hours of the activity, no lasting benefit will be seen. b. yes, because heat acclimatization lowers the sweating threshold and increases sweat rate. c. Yes, because heat acclimatization increases convective heat movement from the core to the skin. d. Yes, because heat acclimatization improves VO2max and lactate threshold, so performance will inevitably improve. e. No, because heat acclimatization causes one to sweat more, removing electrolytes critical to muse function

Yes, because heat acclimatization lowers the sweating threshold and increases sweat rate

If you were going to participate in moderate to vigorous physical activity next August, would it be beneficial to improve your fitness? a. No, because fitness increases sweat rate, which would cause a greater loss of electrolytes. b. No, because increased fitness would improve your VO2max, which means that you would simply exercise at a higher intensity, leading to greater metabolic heat production. c. Yes, because you would sweat less, helping maintain plasma volume. d. Yes, because you would begin to sweat earlier and sweat more, which would blunt the increase in body temperature. e. No, because fitness has no effect on thermoregulation.

Yes, because you would begin to sweat earlier and sweat more, which would blunt the increase in body temperature

Acute mountain sickness (AMS) is: a. a pulmonary disease that manifests itself during prolonged hyperventilation. b. a constellation of symptoms that occurs shortly after arriving at altitude. c. a cardiovascular disease that manifests itself when PaCO2 decreases as a result of hyperventilation. d. getting nauseous when first arriving at altitude.

a constellation of symptoms that occurs shortly after arriving at altitude

During exercise, blood is shunted away from the kidney, liver, and GI tract. This shunting occurs as a result of: a. The increased muscle pump, reducing venous blood volume. b. Changes in the viscosity of the blood. c. Vasodilation in the exercising muscle sucks blood into the legs due to lower blood pressure in the exercising muscle. d. A shift in the balance between metabolism and vascular sympathetic activity toward greater sympathetic activity in the gut.

a shift in the balance between metabolism and vascular sympathetic activity toward greater sympathetic activity in the gut

What term or abbreviation is described by the definition below? "A series of physiological responses that occur in response to prolonged exposure to a change in environmental conditions, which minimize any change in homeostasis." a. Adaptation b. Responsiveness c. Physiological Gain d. Acclimatization

acclimatization

With prolonged exposure to altitude, the primary response by the body in order to maximize O2 delivery to the tissues is: a. an augmented ventilation. b. a decline in total blood volume. c. a shift to anaerobic metabolism as demonstrated by the similar oxygen consumptions for a given task. d. an increase in total hemoglobin content of blood.

an increase in total hemoglobin content of blood

Acute mountain sickness is thought to be caused by: a. an exaggerated hyper ventilatory response which causes the pH in the brain to rapidly increase, drawing fluid out of the vascular space into the brain. b. dehydration. c. an insufficient hyper ventilatory response which leads to fluid retention, resulting in the dilution of plasma proteins causing some of that fluid to move out of the vascular space into the soft tissues. d. brain ischemia caused by the low PaO2 and blood flow associated with acute exposure to hypoxia.

an insufficient hyperventilatory response which leads to fluid retention, resulting in the dilution of plasma proteins causing some of that fluid to move out of the vascular space into the soft tissues

Blood flow through a tissue bed is directly proportional to: a. vascular resistance b. blood volume c. rate-pressure product (i.e. double product) d. blood pressure gradient

blood pressure gradient

Which factor below is the most influential in causing blood lactate concentration to be lower at moderate and high work rates in aerobically trained individuals? a. Because epinephrine levels are lower in trained individuals at these work rates. b. Because intramuscular Ca2+ levels are lower in trained individuals at these work rates. c. Because insulin levels are lower in trained individuals at these work rates. d. Because trained individuals have greater O2 delivery to muscles at these work rates.

because epinephrine levels are lower in trained individuals at these work rates

In order for blood flow to be regulated independently within each organ or tissue bed ________ is regulated systemically, and ________ is regulated locally. a. blood pressure; vascular resistance b. blood volume; mitochondrial density c. vascular resistance; hematocrit d. viscosity; arterial diameter

blood pressure; vascular resistance

Question 9 When outside on a hot day, why do we feel cooler when a breeze blows? a. Convection at the skin surface is greater, moving away hot, saturated air. b. Radiation from environment to sin is less due to the wind deflecting heat waves. c. Conduction is increased due to a greater heat gradient between skin and environment. d. Evaporation is greater because moist air is replaced with dryer air by the wind. e. Both choice 1 and 4 f. Both choice1 and 2

both choice 1 and 4

Temperature sensitive receptors that provide information to the central controller are located in: a. core, skin, and hypothalamus b. skin, muscle, and core c. skin, medulla, and core d. muscle, core, and hypothalamus

core, skin, and hypothalamus

What term or abbreviation is described by the definition below? The volume of gas that does not take part in gas exchange. a. Conducting zone ventilation b. Dead space ventilation c. Dead zone respiration d. Tidal volume e. Alveolar ventilation

dead space ventilation

In general, the higher the intensity of prolonged exercise above the lactate threshold, the greater the relative contribution of... a. PCr to produce ATP. b. glycolysis to produce ATP. c. the Krebs cycle to produce ATP. d. the electron transport chain to produce ATP e. beta oxidation to produce ATP

glycolysis to produce ATP

Compared to type IIx muscle fibers, type I muscle fibers have a ___________ number of mitochondria, and predominantly rely on _______________ metabolism to produce ATP. a. greater, oxidative b. lower, oxidative c. greater, non-oxidative d. lower, non-oxidative

greater, oxidative

Question 14 In order to prevent heat illness when one chooses to exercise in the heat, the first step should be: a. Lose weight b. Exercise in the shade c. Exercise inside d. Hydration

hydration

What term or abbreviation is described by the definition below? "An elevation in body temperature above the hypothalamic set point" a. Thermic Acclimatization b. Thermal threshold c. Hyperthermia d. Hypothermia

hyperthermia

What term or abbreviation is described by the definition below? "An increase in minute ventilation above normal seal level values" a. Ventilatory threshold b. Hypoxemia c. Hypoxia d. Hyperventilation

hyperventilation

What term or abbreviation is described by the definition below? "Reduced delivery of oxygen to the body" a. Hyperventilation b. Hypoxia c. Ventilatory threshold d. Hypoxemia

hypoxia

A decline in blood pH results in a(n) ________ in VE. a. Increase b. No change c. Decrease

increase

Which choice below increase the muscular force produced by a skeletal muscle during movement? a. Increase the action potential frequency in each motor neuron recruited. b. Stop recruiting the small motor units and recruit the large motor units. c. Perform the movement as fast as possible. d. Increase the use of carbohydrate because fat metabolism takes much longer to generate ATP.

increase the action potential frequency in each motor neuron recruited

What is the danger of hyperhydration (drinking too much water too quickly)? a. Increased accumulation of fluid in the kidney leading to renal failure and possible death. b. Increased accumulation of fluid in the brain causing cognitive impairment, seizure, and possibly death. c. Dilution of electrolytes leading to muscle cramps, reduced cerebral perfusion, and possibly death. d. Increased accumulation of fluid in the brain and limbs leading to periorbital or pitting limb edema.

increased accumulation of fluid in the brain causing cognitive impairment, seizure, and possibly death

Heat acclimatization causes which of the following biological responses? a. Increased myocardial contractility b. Shift from apocrine to eccrine sweating c. Decreased sodium absorption d. Increased hemoglobin concentration e. Increased blood volume

increased blood volume

During resistance training, the initial strength gains are primarily due to what? a. Muscle fiber hyperplasia b. Shift in fiber composition from Iix to IIa c. Muscle fiber hypertrophy d. Increased motor unit recruitment e. Decreased intramuscular fat

increased motor unit recruitment

What happens to maximal ventilation (VEmax) after aerobic exercise training? a. It decreases to prevent exercise-incuced hypoxemia. b. It decreases because of the greater cardiac output moving through the pulmonary capillaries after training. c. It increases due to greater alveolar volume that occurs with training. d. It stays the same because maximal ventilation is not limiting factor for aerobic exercise. e. It increases due to greater recruitment of pulmonary muscles.

it increases due to greater recruitment of pulmonary muscles

What happens to the ventilatory threshod with aerobic exercise training? a. It shifts to a lower exercise intensity because epinephrine concentration is lower after training. b. It does not shift because it doesn't feel like it. c. It shifts to a higher exercise intensity because there is a greater reliance on oxidative metabolism, which allows for pH to be maintained until a higher exercise intensity. d. It does not shift because it reflects anaerobic metabolism, which does not change with aerobic exercise training. e. It shifts to the right due to greater diffusion of oxygen in the lungs and greater affinity of hemoglobin for O2

it shifts to a higher exercise intensity because there is a greater reliance on oxidative metabolism, which allows for pH to be maintained until a higher exercise intensity

What term or abbreviation is described by the definition below? Contracting skeletal muscles pushing blood toward the heart. a. Respiratory pump b. Length-tension relationship c. Muscle pump d. Muscle metabolism e. Afterload

muscle pump

Three reasons why oxygen consumption remains elevated following exercise are: a. resynthesis of PCr stores in muscle, depletion of metabolic CO2, elevated body temperature. b. lactate removal, restoration of muscle oxygen stores, elevated body temperature. c. elevated hormones, buffering of H+, elevated body temperature. d. elevated pulmonary ventilation and heart rate, resynthesis of PCr stores and Krebs Cycle intermediates. e. elevated body temperature, maintenance of blood pressure, resynthesis of PCr stores.

lactate removal, restoration of muscle oxygen stores, elevated body temperature

As long as systemic blood pressure is maintained, local tissue blood flow is determined by: a. local blood pressure. b. local blood volume. c. local vascular resistance. d. muscle pump.

local vascular resistance

What term or abbreviation is described by the definition below? The volume of gas inhaled or exhaled from a person's lungs each minute. a. Minute ventilation b. Tidal volume c. Alveolar ventilation d. Respiratory rate

minute ventilation

Endurance training increases __________________ in type IIa fibers, making them function more like ______ fibers. a. the number of myosin; type IIx b. the amount of actin; type Iix c. number of mitochondria; type I d. the speed of ATPase; type I

number of mitochondria; type I

While several environmental factors work together to influence heat dissipation from the body, which factor is most important when determining if it is sage to exercise outside? a. Total environmental radiation b. Temperature c. Wind chill d. Relative humidity

relative humidity

The oxygen cost of a given task (same absolute workload) at altitude: a. is less due to the reliance on anaerobic metabolism b. is lower due to reduced air density reducing the coefficient of drag c. remains about the same as at sea level. d. is greater than at sea level e. depends on the type of exercise (cycling stays the same, running is greater)

remains about the same as at sea level

What term or abbreviation is described by the definition below? The forcing of blood from veins within the abdominal cavity into the veins in the thoracic cavity due to pressure oscillations during pulmonary ventilation. a. EDV b. Respiratory pump c. Venous return d. Muscle pump e. Cardiac output

respiratory pump

When a person saunters (walking in a slow relaxed manner), they primarily recruit ________ motor units. When a person runs fast, they recruit _________ motor units. a. large, small b. small, large c. slow, fast d. small, all types e. large, all motor unit types

small, all types

Even with hyperventilation, PaO2 is typically decreased during exposure to altitude or hypoxia due to a: a. reduced blood volume b. smaller differences between PAO2 and PvO2 c. greater a-v O2 d. increased metabolism

smaller differences between PAO2 and PvO2

What term or abbreviation is described by the definition below? "The hypothalamic drive at which sweating begins to increase exponentially" a. 40 degrees Celsius b. Sweat Threshold c. Metabolic Threshold d. Sweat Rate

sweat threshold

Physiological factors that provide input to the ventilatory centers in the brain that can influence ventilation includes which of the following? a. pH, PACO2, temperature b. exercise intensity, PAO2, movement c. cerebral blood flow, pH, PaO2 d. Temperature, muscle metabolism, pH e. PAO2, PACO2, PaO2, PaCO2

temperature, muscle metabolism, pH

What causes fast-twitch muscle fibers to twitch fast? a. They are bigger than slow-twitch b. They have a lower mitochondrial density. c. The characteristics of the motor nerve that innervates them. d. They have the isoform of ATPase that hydrolyzes ADP

the characteristics of the motor nerve that innervates them

The primary stimulus causing the ventilatory response seen during acute hypoxia is: a. the lower PbO2 which lowers resistance to movement of air in and out of lungs b. a decrease in pH caused by the shift toward anaerobic metabolism c. the decline in PACO2 sensed by the arterial chemoreceptors d. the decline in PaO2 sensed by the arterial chemoreceptors. e. the decline in PaCO2 sensed by the central chemoreceptors

the decline in PaO2 sensed by the arterial chemoreceptors

On a hot day identical twins go out on a run together; one is heat acclimatized, the other is not. You can tell which twin is heat acclimatized because... a. The heat acclimatized twin will not be hyponatremic. b. The heat acclimatized twin drinks less water during the run. c. The heat acclimatized twin is redder in the face following the run. d. The heat acclimatized twin sweats more than the other twin.

the heat acclimatized twin sweats more than the other twin

The term "fast-twitch" or "slow-twitch" is used to talk about what characteristic of the muscle fiber? a. How quickly muscle soreness develops b. Mitochondrial density c. The maximum rate at which they contract d. Which muscle are used to run fast or slow

the maximum rate at which they contract

What factors cause the relative change in fat metabolism as exercise intensity increases? a. The LDH isoform in the muscle fibers recruited, a depletion of glycogen at higher exercise intensities, the greater efficiency of gluconeogenesis. b. The lack of oxygen availability at higher exercise intensities, the change in pH due to lactate accumulation, and the increased ventilatory work. c. The recruitment of type-II muscle fibers at higher exercise intensities, increases in epinephrine, and increases in lactic acid production. d. Recruitment of type-II muscle fibers at higher exercise intensities, the preparation for EPOC, the decline in insulin levels as exercise intensity increases.

the recruitment of type-II muscle fibers at higher exercise intensities, increases in epinephrine, and increases in lactic acid production

As exercise intensity increases, what happens to the relative contribution of fat compared to carbohydrate metabolism? a. The relative contribution of fat as a fuel becomes less because you begin to deplete carbohydrate, which also reduces fat metabolism. b. The relative contribution of fat as a fuel becomes greater because you need more ATP, and you get more ATP from each gram of fat, so burning fat at higher intensities is more efficient. c. The relative contribution of fat as a fuel become less because as exercise intensity increases you recruit more fast-twitch muscle fibers which are primarily glycolytic, and thus rely on carbohydrate as a metabolic substrate. d. The relative contribution of fat as a fuel becomes greater because you begin to deplete your glycogen stores, and must rely on fat as the primary substrate.

the relative contribution of fat as fuel becomes less because as exercise intensity increases you recruit more fast-twitch muscle fibers which are primarily glycolytic, and thus rely on carbohydrate as a metabolic substrate

A fit person agrees to help their unfit friend get in shape for the friend's wedding. When they go out running together on the shores of lake Michigan (12-minutes per mile), which person will have a higher heart rate? a. Fit person b. Unfit person c. Both will have same heart rate

unfit person

An increase in [H+] within a local tissue would lead to: a. a decline in metabolism and vasoconstriction of local arterioles and precapillary sphincters. b. an increase in blood pressure. c. vasodilation of local arterioles and precapillary sphincters. d. both choice 1 and 2

vasodilation of local arterioles and precapillary sphincters

What term or abbreviation is described by the definition below? The rate at which blood flows back to the heart. a. Stroke volume b. Heart rate c. Rate of contractility d. Qc e. VO2 f. Venous return

venous return

What term or abbreviation is described by the definition below? The breakpoint at which pulmonary ventilation and carbon dioxide output begin to increase exponentially during an incremental exercise test. a. Hypoxic threshold b. Cholinergic threshold c. Carbonic threshold d. Lactate threshold e. Ventilatory threshold

ventilatory threshold