Exercise Physiology exam 2

Following a single bout of resistance exercise training, muscle protein synthesis can remain elevated above sedentary levels for as much as ______ in both trained and untrained individuals.

35-50 hours

High responders to endurance exercise training (i.e., individuals that achieve large increases in VO2max) can achieve up to ______% improvement in VO2 max following a prolonged and intense training program.

50

A single bout of resistance exercise training increases muscle protein synthesis by as much as ______% above resting levels.

50-150%

It is estimated that _______% of the differences in muscle mass between individuals can be explained by genetic variation.

80

In theory, concurrent resistance and endurance exercise training can impair muscle protein synthesis following a bout of resistance exercise. The proposed mechanism to explain this inhibition is _____________________________________.

AMP kinase activation of TSC2

the breakdown of ATP in muscle is accomplished via the enzyme

ATPase

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

Prolonged inactivity of skeletal muscle leads to rapid muscle atrophy; this occurs due to:

-decrease in muscle protein -increased protein breakdown in muscle fiber

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 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

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

-increased uptake of fatty acicds -decreased utilization of muscle glycogen -sparing of blood glucose

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

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

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

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

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

-muscles involved in the activity -the fiber types recruited the principal energy system (aerobic vs anaerobic) involved in the activity

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

-myonuclear domain is the region of cytoplasm surrounding an individual nucleus -importance of myonuclear domain is that a single nucleus is responsible fro the genes expression for its surrounding cytoplasm -in response to resistance e exercise, satellite cells become activated and divid to add additional nuclei to a muscle fiber

which of the following statements. about muscle fatigue are true?

-the cause of muscle fatigue during severe exercise is multifactorial and includes increases in phosphate ions and hydrogen ions within the active muscle fibers -increases in hydrogen ions in skeletal muscles contribute to fatigue because hydrogen ions bind to het calcium binding site on troponin

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 in regard to specific force production?

-type iix is greater than type I and type iia - and type iix is slightly greater than type iia

a highly successful endurance athlete would likely have ___ compared to sedentary person

higher percentage of type 1 fibers

A single bout of resistance exercise training results in an increase in skeletal muscle protein synthesis. This exercise-induced increase in muscle protein synthesis can occur within _____ following the exercise session.

hours

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

hours

The term hyperplasia refers to ________________.

increase in total number of muscle fibers

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 endurance training adaptations assist in maintaining acid-base balance during exercise?

increased mitochondrial volume in skeletal muscle

Endurance training has been shown to reduce the oxygen deficit in subjects performing a bout of submaximal exercise. This is likely due to

increases in the number of mitochondria and capillaries.

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

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.

The phenomenon that previous strength training accelerates the re-acquisition of both muscular strength and hypertrophy is commonly referred to as _________.

muscle memory

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

neural adaptation

During the first 8 weeks of a resistance training program, the initial increase in muscular strength is primarily due to

neural adaptations

Muscles receive a neural activation signal from motor neurons located in the spinal cord. This neural signal is referred to as ________.

neural drive

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

neuromuscular junction

Which of the following statements about neurons are NOT true?

neurons repolarize by opening chloride channels on the membrane

Several mechanisms have been proposed to explain why concurrent endurance and resistance (strength) training impedes strength development compared to strength training alone. Which of the following mechanisms have NOT been proposed to explain why concurrent training impedes strength development?

none

The action potential is generated when an excitatory stimulus

opens sodium channels

It is established that resistance exercise training promotes an increase in muscle protein synthesis by activating the mechanistic target of rapamycin (mTOR) which results in increased protein synthesis. Recent evidence suggests that two signaling molecules interact to directly activate mTOR. These molecules are:

phosphatidic acid and Das homologue enriched brain (Rheb)

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

CNS and PNS

kinesthesia

Conscious recognition of the position of body parts with respect to each other

Which of the following statements are true about muscle chemoreceptors?

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

which of the following has been shown to cause muscle fatigue

accumulation of H+ and inorganic phosphate

The neurotransmitter used in the parasympathetic nervous system is

acetylcholine

the two major contractile proteins found in skeletal muscle are

actin and myosin

Several factors contribute to neural drive. Which one of the following factors is NOT a contributor to neural drive?

activation of the Golgi tendon organ

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

afferent

Growing evidence reveals that, independent of resistance exercise, ____________ can activate mTOR and promote small increases in muscle protein synthesis.

amino acid leucine

A muscle (i.e., prime mover) that results in movement of a limb in the desired direction is labeled as _____________.

an antognist

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

an increase in the maximal a-vO2 difference and an increase in maximal cardiac output

Resistance training results in an increase in the rate of contractile protein synthesis which is matched by _________________.

an increase in the synthesis of collagen in tendons and ligaments

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 addition of myonuclei to growing muscle fibers ______________.

appears to be essential for optimal muscle hypertrophy in response to resistance training is likely required to maintain the high level of transcriptional capacity needed to synthesize muscle proteins and allow muscle fibers to grow during resistance training

An excitatory neurotransmitter

both results in graded depolarization of the dentrites and cell body and promotes excitatory postsynaptic potentials 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 joint receptors that provide the central nervous system with information about body position are called

proprioceptors

Which of the following statements about resistance training is NOT true?

resistance training DOES NOT promote hypertrophy and strength gains people greater than 65 years old

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

Aging is associated with a decline in strength, with most of the decline occurring after age 50. The loss of strength is due, in part, to a loss of muscle mass; this age-related loss of muscle mass is termed

sarcopenia

calcium is stored in muscle within the

sarcoplasmic reticulum

By comparison to the rate of detraining following endurance training, the rate of detraining (i.e., loss of muscular strength) following a resistance training program is _________.

slower

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 (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

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

Several hormones have the potential to increase muscle protein synthesis. These include:

testosterone, insulin-like growth factor-1 (IGF-1), and growth hormone

An important physiological factor that may contribute to the inhibition of motor unit activation during resistance training is ____________.

the Golgi tendon

post activation potentiation is defined as

the increase in muscle force production that occurs following a bout of non-fatiguing, sub maximal 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

Neural drive is defined as ___________________________________.

the magnitude of the efferent neural output from the central nervous system to the motor units and the muscle fibers that they activate

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, dendrite, axon

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 cross-education refers to ___________________.

the observation that if one limb engages in resistance training, muscular strength increases in the untrained (contralateral) limb

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

In resting skeletal muscle fibers, Ras homologue enriched brain (Rheb) activation of mTOR is inhibited by ______.

tuberous sclerosis complex 2 (TSC2)

which type of muscle fiber has been shown to be most efficient

type 1

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

type 1 fibers

Resistance training increases the specific force production of ________.

type 1 muscle fiber

the amount of force exerted during unclear contraction is dependent on the

type of motor units recruited, initial length of. muscle, and nature of 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, joint, tendon, and muscle receptors

Research reveals that resistance training induced muscle hypertrophy is associated with an increase in myonuclei. The source of these additional myonuclei is _____________.

via satellite cell activation

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)

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

decrease in maximal heart rate

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

dementai, Alzheimers, impaired mental function

A potential mechanism that could contribute to central fatigue includes

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

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

a muscular contraction that results in a movement of body parts is called

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, stimulate neuron formation

The layer of connective tissue tissues that surrounds the outside of skeletal muscle (below fassicle) is called

epimysium

Neurotransmitters that cause depolarization of membranes are called

excitatory transmitter

distance (endurance) training results in

fast-to-slow shift in muscle fiber types

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 (all)

The thin muscle cells located within the muscle spindle are called

intrafusal fiber

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

irritability

Muscle spindles provide sensory information relative to the

length of muscle