Exercise Physiology Exam #2

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%

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

35-50 hours

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

A decrease in maximal heart rate

The specific tension (i.e force production per cross sectional area of 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

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

The excitatory neurotransmitter

both result in graded depolarization of the dendrites 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 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

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

increased peripheral resistance

One of the proposed mechanisms to explain the positive impact of postactivation potential on muscle performace is that low intensity muscle contractions result in phosphorylation

increasing the muscles sensitivity to calcium

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

MS results in damage to neurons with the basal ganglia

Which of the following statements are true about muscle chemoreceptors

Muscle chemoreceptors respond to changes in the concentration of hydrogen ions

A highly successful endurance athlete would likely have _____ compared a sedentary person

a higher percentage of type I fibers

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

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

an agonist

The thin muscle cells located within the muscle spindle are called

intrafusal fibers

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

muscle memory

Action potential is generated when an excitatory stimulus

opens sodium channels

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

resting membrane potential

The cell membrane around a muscle fiber is called

sarcolemma

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

Postactivation potentiation is defined as

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

The ________ is the organ located in the inner ear and is responsible for maintaining the general equilibrium

vestibular apparatus

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

via satellite cell activation

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

The average VO2 max value for the young (e.g. 21 yrs 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 tp _____% improvement in VO2 max following a prolonged and intense training program.

50

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

AMP kinase activation of TSC2

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 principle energy system (i.e. aerobic vs anaerobic) involved in the activity

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 differences in muscle mass between individuals can be explained by genetic variation

80

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

80

The breakdown of ATP in muscle is accomplished via the enzyme

ATPase

The two major contractile proteins found in skeletal muscle are

actin and myosin

Disease-related muscle wasting is termed

cachexia

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

central and peripheral

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

cerebellum

resistance training results in a

fast-to-slow shift muscle fiber types

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

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

The sodium-potassium pump 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 velocities of movement up to 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 oberservation?

muscle force production decreases with high shortening velocities because fewer cross-bridges are connected and therefore, les 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 adaptations

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

temporal summation

The term cross-education refers to

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

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

type I

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 simulation

Aging is associated with the 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

increased production of radicals in skeletal muscles during periods of prolonged inactivity (prolonged bedrest) and promotes muscle atrophy because:

- oxidative stress activates in muscle fibers - oxidative stress decreases protein synthesis in muscle fibers -oxidative stress prevents mTOR activation

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 trained level -After a period of detraining, approx. 4 weeks of retraining is required to regain the lost mitochondrial volume

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

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 mitochondria 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 improvement in VO2 max?

increase maximal heart rate

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

increased glycogen utilization

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

increased mitochondria volume in skeletal 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

During the first 8 weeks of 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 is neural signal is referred to as

neural drive

Chronic traumatic encephalopathy is associated with

neuronal death, loss of axons, chronic inflammation

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

none of these answers are correct -increased muscle buffer capacity -increased activities of myokinase and creatine phosphokinase

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

none of these are correct neural factors, overtraining, depressed muscle protein synthesis

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 Ras homologue enriched brain (Rheb)

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

The neurotransmitter used in the parasympathetic nervous system is

acetylcholine

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

afferent

resistance training results in an increase of the rate of contractile protein synthesis which is matched by

an increase in the synthesis of collagen in tendons and ligaments

The term hyperplasia refers to

an increase in the total number of muscle fibers

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

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

both a decrease in muscle protein synthesis and increased protein breakdown in muscle fibers 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

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 intercellular and extracellular fluids are correct

The joint receptors that provide the central nervous system with information about the 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 in people greater than 65 yrs old

Aging is associated with a decline in strength, with most of the decline occurring after the age of 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 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 (i.e., IIx) contain a relatively

small number if mitochondria and high ATPase activity

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

spinal tuning

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

stimulate neuron info, improve blood flow, enhance learning and memory

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

sympathetic and parasympathetic

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 organ

Growing evidence reveals that, independent of resistance exercise, _________ can activate mTOR and promote small increase in muscle protein synthesis

the amino acid leucine

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

calcium binding troponin

Neurons can be divided into three basic parts:

cell body, dendrites, axon

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

resistance training increases the specific force production of

type 1 muscle fibers

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

type I fibers

Equilibrium and balance require input from the

Vestibular apparatus, eyes; joint, tendon, and muscle receptors

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 a responsible for the gen expression for its surrounding cytoplasm - In response to resistance exercise, satellite cells become activated and divide to add additional nuclei to a muscle fiber

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

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

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)

The addition of myonuclei to growing muscle fibers

Both appears to be essential for optimal muscle hypertrophy in response to resistance training and is likely required training and 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 are correct

Which of the following statements about muscle fatigue are true?

Both 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

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

Both moderate intensity 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 60-70% VO2 max are correct

which of the following events occurs first during a voluntary muscle contraction

The innervating alpha-motor neuron reaches an action potential

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

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

dementia, Alzheimer's disease, impaired mental function

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

dynamic contraction

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

efferent

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

epimysium

Neurotransmitter that cause depolarization of membranes are called

excitatory transmitters

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

irritability

Muscle spindles provide sensory information relative to the

length of muscle

A major regulator of protein synthesis and muscle size is

mTOR