Knes 203 Midterm

Front 1

What is the definition of physical activity?

Back 1

Physical activity encompasses all leisure and non-leisure body movement produced by the skeletal muscles, which results in an increase in energy expenditure over resting levels.

Front 2

What are the four classifications of physical activity?

Back 2

- Occupational

- Domestic

- Transportation

- Leisure-time

Front 3

What is the definition of physical fitness?

Back 3

A set of attributes or characteristics that people have (or achieve) that relates to their ability to perform physical activity

Front 4

What are the two categories that physical fitness are categorized into?

Back 4

- General fitness (a state of health and well being)

- Specific fitness (a task oriented definition based on the ability to perform specific aspects of a sport or physically demanding occupation)

Front 5

Define health-related fitness

Back 5

Ability to carry out daily tasks with vigor and alertness, without undue fatigue, and with ample energy to enjoy leisure-time pursuits and meet unforeseen emergencies.

Front 6

Define performance-related fitness

Back 6

Physical training for a specific task like a recreational sport or a physically demanding job.

Front 7

What is the main risk of being physically inactive?

Back 7

The fact that it is recognized as 1 of 4 common risk factors for non-communicable diseases. Also it's ranked 4th among the 5 leading causes of global mortality.

Front 8

Define a MET

Back 8

-Metabolic Equivalent

-Amount of energy used for resting metabolism

Front 9

What does 1 MET equal to?

Back 9

1 MET = resting VO2 = 3.5mL x kg-1 x min-1

Front 10

What are the four components of physical fitness?

Back 10

-flexibility

-cardiovascular

-musculoskeletal

-body composition

Front 11

Define cardiovascular fitness

Back 11

The ability of the cardiovascular and cardiopulmonary systems to deliver an adequate supple of O2 to the working muscles.

Front 12

What is VO2max?

Back 12

The oxygen uptake attained during maximal exercise intensity that could not be increased despite further increases in exercise workload.

Front 13

What are the components of VO2?

Back 13

Q x a-VO2diff

HR x SV (CaO2 - CvO2)

Front 14

What are the four factors that determines VO2max?

Back 14

-Pulmonary diffusing capacity

-Maximal cardiac output

-O2 carrying capacity

-Skeletal muscle characteristics

Front 15

What are the two types of musculoskeletal endurance?

Back 15

- Strength endurance: capacity to resist fatigue during repeated contractions with loads greater than 30% of maximum concentric strength

- Muscle endurance: the ability of a muscle to resist fatigue during repeated contractions

Front 16

What type of musculoskeletal fitness are there?

Back 16

-Muscular endurance

-Muscular strength

-Muscular power

Front 17

Define muscular strength

Back 17

maximum force developed by a muscle/muscle group in a single maximal voluntary contraction

Front 18

Define muscular power

Back 18

ability to produce a large amount of work in a short period time (rate of performing work)

Front 19

define flexibility

Back 19

range of motion around a joint or series of joints

Front 20

why is body composition important ?

Back 20

assessing body weight (BW) and body fat (BF) distribution is important. Excess BF increases risks of health problems

Front 21

What are 4 ways to asses body composition?

Back 21

-Hydrostatic weighing

-Skinfold measurements

-Bioelectrical impendence (electric thing with hands)

-DXA, MRI, CT scans

Front 22

Epimysium

Back 22

Surrounds entire muscle and blends into intramuscular tissue sheaths to form tendons

Front 23

Perimysium

Back 23

Surrounds a bundle of fibers called fasciculus

Front 24

Endomysium

Back 24

wraps each muscle fiber and separates it from neighbouring fibers

Front 25

sarcolemma

Back 25

surrounds each muscle fiber and encloses fiber's cellular contents

Front 26

sarcoplasm

Back 26

contains nuclei that house genes, mitochondria, and other specialized cells

Front 27

sarcoplasmic reticulum

Back 27

provides structural integrity

Front 28

tendons

Back 28

connect both ends of muscle to periosteum (bone's outermost covering)

Front 29

difference between origin and insertion of a muscle

Back 29

-origin: where the tendon joins a relatively stable skeletal part, generally the proximal end

- Insertion: the point of distal attachment to the moving bone

Front 30

Skeletal muscle blood supply

Back 30

blood flow oscillates during rhythmic activities (vessels compress during contraction, open during relaxing)

Front 31

Skeletal muscle microstructure

Back 31

•Single multinucleatedmusclefibercontainsmyofibrils thatlie parallelto fiber’slongaxis

•Myofibrils containsmallersubunitscalledmyofilaments thatlieparalleltolongaxisof myofibril

•Myofilaments consistofactinandmyosinthataccount for~85%of myofibrillar complex

•Other proteinseitherservestructuralfunctionor affectproteinfilament interactionsduringmuscleaction

•Tropomyosin, troponin,α-actinin,β-actinin, M protein,andCprotein

Front 32

Myofibril has a cross-striation pattern:

Back 32

•I band represents lighterarea

•A band represents darkerarea

•CenterofAband containsthe H zone

•M band bisectsH zone;and consistsof proteinstructures thatsupport arrangement of myosinfilaments

•Zline bisectsI bandand adheres to sarcolemmatoprovidestructuralstability

Front 33

what is the skeletal muscle microstructure of a sarcomere?

Back 33

consists of basic repeating unit between two z lines; comprises the functional unit muscle fiber

Front 34

How do muscle fibers shorten?

Back 34

Occurs due to the movement of the actin filament over the myosin filament (myosin crossbridges cyclically attach, rotate and detach from actin filaments with energy from ATP hydrolysis)

Front 35

Step 1 of sequence of events in muscle action

Back 35

Generationof actionpotentialinmotor neuron causes terminal axontorelease acetylcholine (ACh),whichdiffusesacross synaptic cleft andattachestospecialized AChreceptorsonsarcolemma

Front 36

Step 2 of sequence of events in muscle action

Back 36

Muscle action potential depolarizes the transverse tubules at sarcomere's A-I junction

Front 37

Step 3 of sequence of events in muscle action

Back 37

depolarization of t-tubule system causes calcium release from lateral sacs of sarcoplasmic reticulum

Front 38

Step 4 of sequence of events in muscle action

Back 38

calcium binds to troponin-tropomyosin in actin filaments, releasing the inhibition that prevented actin from combining with myosin

Front 39

Step 5 of sequence of events in muscle action

Back 39

-Actin combines with myosin-ATP; this activates myosin ATPase, which splits ATP

-The reaction's energy produces myosin crossbridge movement and creates tension

Front 40

Step 6 of sequence of events in muscle action

Back 40

•ATPbindstomyosincrossbridgewhich breaksactin–myosinbond,allowing actin disassociation fromthecrossbridge

•Thickand thin filamentsthen slidepasteach other and muscleshortens

Front 41

Step 7 of sequence of events in muscle action

Back 41

Crossbridgeactivation continueswhenCa2+ concentrationremainshighenough toinhibit troponin–tropomyosinsystem

Front 42

Step 8 of sequence of events in muscle action

Back 42

Whenmuscle stimulationceases, intracellularCa2+ concentrationrapidly decreasesasCa2+ movesbackintolateral sacsof sarcoplasmicreticulum through active transport; requiresATPhydrolysis

Front 43

Step 9 in sequence of events in muscle action

Back 43

•Ca2+ removalrestores inhibitoryactionof troponin–tropomyosin

•Inpresenceof ATP,actinand myosinremain in dissociated,relaxedstate

Front 44

What four characteristics do type 2 fibers display?

Back 44

1.Highcapabilityforelectrochemical transmissionofactionpotentials

2.High myosinATPaseactivity

3.RapidCa2+ releaseand uptakeby efficient sarcoplasmicreticulum

4.High rateofcrossbridgeturnover

Front 45

Type 2 fibers:

Back 45

•Intrinsicspeed of shortening and tensiondevelopmentrangesfrom 3to 5 times fasterthanslow-twitchfibers

•Relyonwell-developed,short-term glycolytic system forenergytransfer

•Activationpredominates in anaerobic-typesprintactivitiesand other forcefulmuscleactionsthatrely entirely on anaerobic energy transfer

•Activationplaysan importantrole in stop-and-goorchange-of-pace sports such as basketball, soccer,tennis,etc.

Front 46

What do type 1 fibers do?

Back 46

Generate energy for ATP resynthesis through aerobic system of energy transfer

Front 47

what are the four distinguishes characteristics of type 1 fibers?

Back 47

1.Low myosinATPaseactivity

2.Slowcalciumhandling ability and shorteningspeed

3.Lesswell-developed glycolyticcapacity than fast-twitchfibers

4.Large andnumerousmitochondria

Front 48

Main difference between type 1 and type 2 fibers

Back 48

type 1 is more fatigue resistant, type 2 is more spontaneous

Front 49

Define a motor unit

Back 49

-makes up functional unit of movement

-consists of a motor neuron and specific muscle fibers it innervates

*each muscle fiber generally receives input from only 1 motor neuron; a motor neuron may innervate many muscle fibers*

Front 50

Motor unit functional characteristics:

Back 50

based on three physiological and mechanical properties of the muscle fibers they innervate

-twitch characteristics

-tension characteristics

-fatigue

Front 51

What are the three training principles?

Back 51

-Overload

-Progression

-Specificity

Front 52

What is meant by "overload" when in comes to training principles?

Back 52

- Thetraining stimulus must be greaterthan thattowhichthebody isaccustomed.

- Increasefrequency,intensity, durationor thenumberof repetitions and sets, or decreasethe recoverytimein aprogram.

Front 53

What is meant by "progression" when in comes to training principles?

Back 53

- Theinitialworkloadmustincrease (progress) toensure continued improvement.

Front 54

What is meant by "specificity" when in comes to training principles?

Back 54

Training effects arespecific to the energy system used (i.e.,aerobic or anaerobic), as well asthe muscle groups, joint actions and type/speed of muscle contraction.

Front 55

What are the six main types of muscle actions?

Back 55

-Concentric

-Isometric

-Eccentric

-Dynamic constant contraction

-Dynamic variable contraction

-Isokinetic muscle contraction

Front 56

What is a concentric muscle action?

Back 56

The tension developed in the cross-bridges of a muscle is sufficient to overcome any resistance to shortening

Front 57

What is an isometric muscle action?

Back 57

The tension in the cross-bridges equals the resistance to shortening, and the muscle length remains relatively constant

Front 58

What is an eccentric muscle action?

Back 58

The tensionin the cross-bridgesisless thantheexternal resistanceandthemuscle lengthensdespitecontactbetweenmyosin cross-bridgesheadsand actinfilaments.

Front 59

what is dynamic constant contraction?

Back 59

muscle action against a constant external resistance (isotonic) ex: free weights

Front 60

what is dynamic variable contraction?

Back 60

muscle action against a changing external resistance. ex: bungee or band

Front 61

what is isokinetic muscle contraction?

Back 61

muscle action which occurs at a constant velocity allowing for maximal force generation throughout the entire movement (biodex)

Front 62

Exercise order:

Back 62

power --> non power (core) --> assistance exercise (leg press and such)

Front 63

what is plyometric training?

Back 63

a quick, powerful movement using a pre-stretch, or countermovement, that involves the stretch-shortening muscle

Front 64

how does plyometric training help improve?

Back 64

muscle force and power production, which is explained by two proposed models (mechanical model, neurophysiological model)

Front 65

What is the mechanical model in plyometric training?

Back 65

-elastic energy of the musculotendious components is increased with rapid stretch (eccentric action) and then stored

-if immediately followed by a concentric action, the stored energy is released and force production increased

-most of the elastic component in the system is in the tendons. the system acts as a spring, which stores energy as it is lengthened

Front 66

What is the neurophysiological model in plyometric training?

Back 66

-the stretch reflex is the body's response to an external stimulus that stretches the muscle

-muscle spindles are proprioceptive organs that are sensitive the rate and magnitude of the stretch

-when a quick stretch is detected, muscular activity reflexively increases and muscle fibers contract

-plyometric exercises produce rapid stretches and stimulate the muscle spindles, causing a reflexive muscle action, which increases force production

Front 67

what are neural adaptations?

Back 67

adaptive altercations in nervous system function that elevate motor neuron output account for rapid and large strength increases early in training, without increases in muscle size and CSA

Front 68

difference between intermuscular and intramuscle coordination?

Back 68

-inter: improved feedback between muscles and CNS, improved coordination of MU activation (size principle)

-intra: rate of MU firing, number of MU recruited, sychronization of the signal

Front 69

Muscular adaptations (hypertrophy)

Back 69

Increase in muscular tension (forcing) with training provides main stimulus to initiate muscle growth

Front 70

how does ATP form?

Back 70

ATP forms from adenosine linked to three phosphate

Front 71

how does ADP form?

Back 71

when ATP joins with water, catalyzed by the enzyme adenosine triphosphate (ATPase)

Front 72

what is the PCr system?

Back 72

the energy reservoir - some energy for ATP resynthesis comes from anaerobic splitting of a phosphate from PCr