Exercise phys uark exam 2

Endurance exercise training programs (e.g., 3 days/week @ 60% VO2 max for 12 weeks) typically results in a ______.

15-25% improvement in VO2 max

Four-to-ten weeks of anaerobic training (high intensity exercise lasting 10-30 seconds) can increase the peak anaerobic capacity by ______ across individuals.

3-25%

The average VO2 max value for the young (e.g., 21 years old) male sedentary population is approximately

45 ml • kg-1 • min-1.

Heritability (i.e., genetics) determines approximately _____% of VO2 max variability in sedentary adults.

50%

High responders to endurance exercise training (i.e., individuals that achieve large increases in VO2 max) can achieve up to ______% improvement in VO2 max following a prolonged and intense training program.

50%

Which of the following factors DO NOT contribute to the decline in VO2 observed during 84 days of detraining?

A decrease in maximal heart rate

The breakdown of ATP in muscle is accomplished via the enzyme

ATPase

The force velocity curve describes the relationship between speed of muscle shortening (i.e., velocity of movement) and muscle force production. Which of the following statements are true about the influence of muscle fiber type on the force velocity curve?

At any given velocity of movement, the peak power generated is greater in a muscle that contains a high percentage of fast fibers (i.e., type IIx) compared with a muscle that contains a high percentage of slow fibers (i.e., type I).

Four categories (domains) of exercise intensity exist. Which of the following statements about exercise intensity domains are true?

Both Moderate intensity exercise is below the lactate threshold and typically below 60% VO2 max in untrained subjects and Heavy exercise is exercise above the lactate threshold and typically ranges between 60-75% VO2 max are correct

Which of the following statements about muscle fatigue are true?

Both the cause of muscle fatigue during severe exercise is multifactorial and includes increases in phosphate ions and hydrogen ions within the active muscle fibers and Increases in hydrogen ions in skeletal muscle contribute to fatigue because hydrogen ions bind to the calcium binding site on troponin are true.

A popular belief among some athletes is that exercise-induced muscle cramps in a single muscle (e.g., gastrocnemius) results from dehydration and blood electrolyte imbalance. Which of the following observations DO NOT support this position?

Dehydration and electrolyte imbalance would likely impact all skeletal muscles., Exercise-induced muscle cramps can occur without any change in blood electrolyte concentrations., Static stretching of the cramping muscle often relieves the cramp.

Which of the following statements are true about the effect of endurance training or detraining on mitochondria volume in human skeletal muscle?

Five weeks of endurance training can increase skeletal muscle mitochondrial volume by two times about normal., Seven days of detraining can reduce mitochondrial volume by 50% below the trained level., After a period of detraining, approximately 4 weeks of retraining is required to regain the lost mitochondrial volume.

Which of the following statements about multiple sclerosis (MS) are NOT true?

MS results in damage to neurons within the basal ganglia.

Which of the following statements are true about muscle chemoreceptors?

Muscle chemoreceptors respond to changes in the concentration of hydrogen ions.

Aging is associated with a loss of muscle mass; this is called sarcopenia. Which of the following statements about sarcopenia are correct?

Muscle mass begins to decline around age 25, The slow phase of age-related muscle decline ranges from age 25 to 50 years, By age 80, 50% of the total muscle mass can be lost

Which of the following statements about neurons are NOT true?

Neurons repolarize by opening chloride channels on the membrane.

Which of the following training adaptations does NOT occur in skeletal muscles following 4-10 weeks of anaerobic exercise training?

None of these answers is correct

Which of the following events occurs first during a voluntary muscle contraction?

The innervating alpha-motor neuron reaches an action potential.

Which of the following statements about the myonuclear domain are correct?

The myonuclear domain is the region of cytoplasm surrounding an individual nucleus., The is importance of the myonuclear domain is that a single nucleus is responsible for the gene expression for its surrounding cytoplasm., In response to resistance exercise, satellite cells become activated and divide to add additional nuclei to a muscle fiber.

A highly successful endurance athlete would likely have ________________ compared to a sedentary person.

a higher percentage of type I fibers

The neurotransmitter used in the parasympathetic nervous system is

acetylcholine

The two major contractile proteins found in skeletal muscle are

actin and myosin

Nerve fibers that carry impulses toward the central nervous system are called

afferent

Endurance exercise training has been shown to improve brain function in numerous ways. Which of the following exercise-induced changes in the brain are NOT linked to exercise-induced improvement in cognition?

angiogenesis in the cerebellum

The increase in VO2 max that occurs following 16 months of endurance exercise training results from

both an increase in the maximal a-vO2 difference and an increase in maximal cardiac output are correct.

A potential mechanism that could contribute to central fatigue includes

both depletion of excitatory neurotransmitters in the brain and a decrease in the excitability of the motor cortex are correct.

The negative membrane potential in a resting neuron is primarily due to

both diffusion of potassium out of the cell and a higher permeability of the membrane for potassium compared to sodium are correct.

An excitatory neurotransmitter

both results in graded depolarization of the dentrites and cell body and promotes excitatory postsynaptic potentials are correct.

Which of the following has been shown to cause muscle fatigue?

both the accumulation H+ and the accumulation of inorganic phosphate are correct

The resting membrane potential of neurons is determined by

both the permeability of the cell membrane to various ions and the difference in ion concentration between the intracellular and extracellular fluids are correct.

The specific tension (i.e., force production per cross sectional area of the fiber) differs between fiber types. Which of the following answers is correct relative to specific force production?

both type IIx is greater than type I and IIa and type IIx is slightly greater than type IIa are correct.

Disease-related muscle wasting is termed

cachexia.

The formation of cross-bridges that initiates the contractile process in skeletal muscle is triggered by

calcium binding to troponin

Neurons can be divided into three basic components:

cell body, dendrites, and axon.

Anatomically, the nervous system can be divided into two main parts:

central nervous system and peripheral nervous system.

The area of the brain that aids in control of movement and may initiate fast ballistic movements is the

cerebellum

The motor cortex is concerned with voluntary movement and is located within the

cerebrum

The term kinesthesia refers to

conscious recognition of the position of body parts with respect to each other.

Satellite cells

contribute to muscle growth by dividing and contributing nuclei to existing muscle fibers., reside above the sarcolemma., are undifferentiated cells that play a key role in muscle growth and repair.

Repeated sport-related traumatic brain injuries (i.e., concussions) are associated with a higher risk of developing _________.

dementia, alzheimers, impaired mental function (all of these)

A muscular contraction that results in a movement of body parts is called a(n)

dynamic contraction

Nerve fibers that conduct impulses away from the central nervous system are called

efferent

Relative to brain health, regular aerobic exercise has been shown to

enhance learning and memory, improve brain blood flow, and stimulate neuron formation (all of these are correct)

The layer of connective tissue that surrounds the outside of skeletal muscle (i.e., just below the fascia) is called the

epimysium

Neurotransmitters that cause depolarization of membranes are called

excitatory transmitters.

Following an acute bout of endurance exercise training, the increase in mitochondrial biogenesis occurs within _____ following the completion of the exercise session.

hours

Which of the following factors DO NOT contribute to the endurance exercise training-induced increases in fat metabolism during exercise?

increased fat storage in the liver

Which of the following endurance training adaptations does NOT result in lower lactate production in the contracting muscles?

increased glycogen utilization

Which of the following physiological factors does NOT contribute to the endurance exercise training-induced increase in the maximal a-vO2 difference?

increased hemoglobin in the blood

Which of the following factors do not contribute to the endurance exercise training-induced improvement in VO2 max?

increased maximal heart rate

Which of the following endurance training adaptations assist in maintaining acid-base balance during exercise?

increased mitochondrial volume in skeletal muscle

Which of the following factors does NOT contribute to the endurance exercise training-induced improvement in stroke volume during exercise?

increased peripheral resistance

The enhanced capacity of the trained muscle to use fatty acids as a fuel results in

increased uptake of fatty acids., decreased utilization of muscle glycogen., sparing of blood glucose

One of the proposed mechanisms to explain the positive impact of postactivation potential on muscle performance is that low intensity muscle contractions result in phosphorylation of myosin light chains (i.e., proteins located at the base of the myosin cross-bridge). This increased phosphorylation can increase muscle force production by

increasing the muscle's sensitivity to calcium.

The thin muscle cells located within the muscle spindle are called

intrafusal fibers

The ability of a neuron to respond to a stimulus is termed

irritability

Muscle spindles provide sensory information relative to the

length of muscle

Following an acute bout of endurance exercise training, the rise in the activity of calcinuneurin, calmodulin kinase, and AMP kinases occurs within _____ following the exercise session.

minutes

The removal of damaged mitochondria in skeletal muscle and other cells is called

mitochondria endocytosis.

Endurance exercise training results in an increase in mitochondria volume within skeletal muscle fibers. The process of synthesizing mitochondria in cells is called ______.

mitochondrial biogenesis

A "movement plan" is first developed by the _________________ before being sent to spinal centers for modification.

motor cortex

The motor neuron and all the muscle fibers it innervates is called a ______.

motor unit

The sodium-potassium pump in neurons is an active transport pump that

moves 3 molecules of sodium out of the cell and returns 2 molecules of potassium into the cell.

The peak power generated by any skeletal muscle increases with increasing velocities of movement up to a movement speed of 200-300 degrees per second; at higher shortening velocities, the peak power output declines. Which of the following factors can explain this observation?

muscle force production decreases with high shortening velocities because fewer cross-bridges are connected and therefore, less force is produced.

During the first four months of an endurance exercise training program, the initial increase in VO2 max is primarily due to

neural adaptions

The connecting point between a motor neuron and muscle fiber is called the

neuromuscular junction.

Chronic traumatic encephalopathy is associated with

neuronal death, loss of axons, chronic inflammation (All of these)

The action potential is generated when an excitatory stimulus

opens sodium channels.

The joint receptors that provide the central nervous system with information about body position are called

proprioceptors.

Neurons are negatively charged on the inside of the cell with respect to the charge on the exterior of the cell. This electrical charge difference is called

resting membrane potential

The cell membrane around a muscle fiber is called the

sarcolemma

Calcium is stored in muscle within the

sarcoplasmic reticulum

The mechanism responsible for the size principle is that compared to large motor neurons,

small motor neurons have a small surface area and are easier to depolarize.

Fast-twitch fibers (i.e., type IIx) contain a relatively

small number of mitochondria and high ATPase activity.

Endurance training results in increased mitochondrial and capillary density in muscle but has no effect on muscle glycolytic capacity. This is an example of what training principle?

specificity

Higher brain centers are responsible for developing a general pattern of movement; the specific details of this movement are refined via a process known as ______.

spinal tuning

Cross-sectional studies demonstrate that the physiological variable responsible for the large variation in VO2 max across the normal (untrained) population is maximal

stroke volume

The autonomic nervous system can be divided into two functional and anatomical divisions called

sympathetic and parasympathetic.

The summing of many excitatory post-synaptic potentials (EPSPs) from a single pre-synaptic neuron over a short time period is called

temporal summation

The Golgi tendon organs monitor

tension produced by muscular contraction.

Postactivation potentiation is defined as

the increase in muscle force production that occurs following a bout of non-fatiguing, submaximal contractions.

Following several weeks of endurance exercise training, the capacity to transport glucose into skeletal muscle fibers is increased. Which of the following training-induced changes contribute to this training effect?

the increase in the number of GLUT4 glucose transporters

The principle of specificity of training refers to the fact that exercise training is specific to

the muscles involved in the activity., the fiber types recruited., the principal energy system (i.e., aerobic vs. anaerobic) involved in the activity.

The heart rate and ventilatory responses to constant load submaximal exercise are lower (i.e., lower heart rate and lower minute ventilation) following an endurance training program. This training-induced adaptation is primarily due to changes in the

trained skeletal muscles

Which type of muscle fiber has been shown to be the most efficient?

type I

Skeletal muscle fibers that contain high numbers of mitochondria could be classified as

type I fibers.

The amount of force exerted during muscular contraction is dependent on the

type of motor units recruited, the initial length of the muscle, and the nature of the neural stimulation.

The ______________________ is an organ located in the inner ear and is responsible for maintaining general equilibrium.

vestibular apparatus

Equilibrium and balance require input from the

vestibular apparatus, eyes, joints, tendon, and muscle receptors (All of these are correct)