Physio Report Expt 9

8/6/2019 Physio Report Expt 9

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MuscularStrength and

EnduranceReyes Rodil Sanchez Sarmiento

Sazon


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Objectives

TO DEMONSTRATE HOW TO MEASURESTRENGTH AND ENDURANCE


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Materials

HAND DYNAMOMETER


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Procedures

The subjects arm was placed adducted at

the side with elbow flexed in 90r using the

dominant hand.

The dynamometer was held and squeezed

as hard as possible and the grip strength

was recorded. It was done for three times

and the average of the three was used as

the maximum grip strength.


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Procedures

After one minute rest, the subject performed

twenty consecutive grip contractions

(maximal contraction) at a rate of one every

two seconds.

Total kilograms of force exerted for the

twenty contractions and the average force of

these contractions were recorded.


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Procedures

The maximum grip strength, total force

for twenty contractions and the average

force for the twenty contractions of all thegroups of the class were recorded.

Mean values and ranges for the class were

computed.

The groups grip strength measurements

were compared to the other groups of the

class.


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Results(Mean and Range all in kilograms)


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Results


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Results


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Results


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Results


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Definition of Terms

Endurance

Ability to perform low-intensity, repetitive, or

sustained activities over a prolonged periodof time.

Power

Related to strength and speed of movementand is defined as work; rate of performingwork

Power = work/time


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Definition of terms

Strength

Ability of contractile tissue toproduce tension and a resultant

force based on the determinants

placed on the muscle

Greatest measurable force thatcan be exerted by a muscle or

group of muscle to overcome

resistance during a single

maximum effort


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Definition of terms

Hypertrophy

Increase in the cross-sectional size of a fiberor cell


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Microscopic Level

Review of muscle contraction

http://www.brookscole.com/chemistry_d/templa

tes/student_resources/shared_resources/ani

mations/muscles/muscles.html


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Macroscopic Level

Skeletal fibers

Single, very long , cylindrical,multinucleated cells

Largest among the muscle fiber types

Striated and voluntary muscles Has the ability to contract rapidly and

exert tremendous power

Fatigues easily


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Macroscopic Level

Connective tissue

Endomysium

Encloses each muscle fibers

Perimysium

Encloses each muscle fasicles

Epimysium

Encloses bundles of musclefasicles


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Macroscopic Level

Fast twitchGlycolytic (Type

II B)

Fast twitchOxidative

Glycolytic (Type

II A)

Slow twitchOxidative (Type

I)

Diameter Large Large Small

Muscle color White Red RedRate of fatigue Fast fatigable Fast resistant to

fatigue

Slow

Speed of

contraction

Fast Fast Slow

Axon conduction

velocity

Fast Fast Slow

Glycolytic

capacity

High High Moderate

Oxidative

capacity

Low Moderate High


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Macroscopic Level

Muscle Fiber Arrangement

Convergent Fascicles converge in a single

insertion tendon

Such muscles are fan-shapedand triangular

Fusiform Spindle-shaped muscle with

an expanded belly

Parallel Length of the fascicles run

parallel to the long axis of the

muscle

Strap-like


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Macroscopic Level

Muscle Fiber Arrangement

Circular Muscle fibers arranged in

concentric rings sphincter muscles

Pennate Feather-like Short fascicles attach obliquely

to a central tendon

Unipennate only one side of the

tendonBipennate two sides of the

tendonMultipennate several sides of

the tendon


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FUNCTIONAL STRENGTH

Ability of neuromuscular system to produce,

reduce or control forces, contemplated or

imposed, during functional activities, in a

smooth coordinated manner

Most strength training exercises employ the

full range of motion capable of a joint


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STRENGTH TRAINING

A systematic procedure of muscle or musclegroup lifting, lowering or controlling heavyloads (resistance) for a relatively low numberof repetitions or over a short period of time

Neural adaptations and an increase inmuscle fiber size Increase in themaximum force-producing capacity ofmuscle

Leads to an increase in diameter of

ligaments and tendons, thereby increasingtheir ability to withstand tension and tears


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POWER

Related to strength and movement

Work (force x distance) produced by amuscle per unit time (force x distance/time)

Rate of performing work

Affected by the rate at which the musclecontracts and produces a resultant force and

the relationship of force and velocity

Can be expressed in a single burst of high-intensity activity orby repeated bursts of

less intense muscle activity


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POWER TRAINING

Muscle strength is necessary

Must be used to activate motor units asquickly as possible

Consequence of adaptation in the form ofbetter synchronization of motor units and

their firing pattern, and enhanced

neuromuscular coordination

There is improved co-ordination betweenagonist and antagonist muscles


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POWER TRAINING

Increasing the work of muscle in a specifiedperiod of time or reducing amount of time

required to produce a given force

Greater intensity, shorter period of time greater muscle power

Light weights with a fast or explosive actionare needed for power training


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ENDURANCE

Ability to perform low-intensity,repetitive or sustained activities

over a prolonged period of time

Ability of a muscle to contractrepeatedly against a load, generate

and sustain tension, and resist

fatigue over an extended period of

time

Aerobic power


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ENDURANCE TRAINING

Muscle contract and lift or lower a light loadfor many repetitions or sustain a muscle

contraction for an extended period of time

Low intensity muscle contractions, largenumber of repetitions, prolonged period of

time

Muscles adapt to endurance training byincreases in their oxidative and metabolic

capacities which allows better delivery anduse of oxygen


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TYPES OF CONTRACTIONIsotonic Contraction

Concentric Contraction

Eccentric Contraction

Isometric Contraction

Isokinetic Contraction

Isometric ContractionNo change in the length of the contracting muscle

Isokinetic Contraction

Change in length in a constant speed


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TYP

ES OF CONTRACTION

Isotonic Contraction

Change in muscle length as it contractsand causes movement of a body part

TYPES OF ISOTONICCONTRACTION:

Concentric

Muscle shortens as it contracts

Eccentric

Muscle lengthens as it contracts


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Factors that affect muscle

strength and endurance

MUSCLE FIBER TYPE

SPEED OF MUSCLE CONTRACTION(Force-Velocity Relationship)

FIBER ARRANGEMENT & FIBER LENGTH(Cross-sectional diameter of muscle)

MUSCLE SIZE

MOTOR UNIT RECRUITED

METABOLICCAPACITY

% BODY FAT


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TYPE I

Less strength

Greater endurance


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TYPE II (A & B)

Greater strength

Less endurance


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Concentric

With greater velocity:

Decrease tension

Eccentric

With greater velocity:Increase tension


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Short Fiber

Increase force production


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Long and Parallel

Decrease force production,Increase rate of shortening


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Greater muscle size:

Increase tension


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Less muscle size:

Decrease tension


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Greater motor unitsrecruited:

Increase force

production


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Aerobic increases endurance

Anaerobic decreases endurance


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% BODY FAT

More Body fat

Decrease in endurance


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INCREASING ENDURANCE

Can be achieved through:

Low intensity

Large number of repetitions

Prolonged period of time


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INCREASINGPOWER

Can be achieved through:

high intensity

shorter time

isotonic weight training

ballistic training

pylometrics


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ISOTONICWEIGHT

TRAINING


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BALLISTIC TRAINING

The fast, ballistic application of force ispossible due to quick recruitment of fast-

twitch muscle fibers and effective

coordination of agonist and antagonist

muscle fibers.

EXAMPLE: Various types of medicine ballthrows or stretching rubber cords fixed at

one end. A typical routine would incorporate

35 sets of 1020 explosive repetitions with

a 23 minute recovery between sets.


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PLYOMETRIC TRAINING

It involves exercise in which the muscle isfirst loaded in an eccentric (lengthening)

contraction followed immediately by a

concentric (shortening) contraction

Results in recruitment of most of the motorunits in corresponding muscle fibers, the

transformation of strength into power, and

the development of the nervous system to

react with maximum speed and thereby

generate greater force


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PLYOMETRIC TRAINING

EXAMPLE:

Jumping from a low bench to the floor andimmediatelyjumping up explosively,

bounding such as in a triple jump, hoppingover a low hurdle and immediately

jumping up high, catching a medicine ball

behind your head and immediately

throwing it forwards and upwards and so

on.

The total number of repetitions in a trainingsession is high normally 520 sets of 515

repetitions with a 38 minute recovery.


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MUSCLE HYP

ERTROP

HY

Sarcoplasmic hypertrophy

Growth of sarcoplasm and non-contractileproteins

Do not directly contribute to musclestrength

Myofibrillar hypertrophy

Enlargement of muscle fiber

More myofibrils = more actin and myosin

Affects muscle force production


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Energetic Theory of

Hypertrophy


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Can isometric exercise

increase strength?

Yes, dependent on many factors such as:

Intensity of muscle contraction

Duration of muscle activation

Repetitive contractions

Joint angle

Mode specificity


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Conclusion

Muscular strength can be measured byputting resistance on a muscle or musclegroup

Endurance is the ability of the muscles toresist fatigue for a long period of time.

Endurance is the proper utilization ofbody toconserve energy while in the course ofbeingfunctional.

Hypertrophy is an increase in the cross-sectional size of a fiber or cell.

Hypertrophy is achieved throughsarcoplasmic or myofibrillar hypertrophy.


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References

McGinnis, Peter M. Biomechanics of Sport &Exercise. 1999. United States of America.

Kisner, Carolyn & Colby, Lynn Allen.

Therapeutic Exercise: Foundation andTechniques. (5th edition). 2007. Philadelphia:

F.A. Davis Company.

Zatsiorsky, Vladimir M. and Kraemer, WilliamJ. Science and practice of strength training.

(2nd edition). 2006. USA: Human Kinetics.

Documents

Physio Report Expt 9