Muscular Control of Muscular Control of MovementMovement

Review of AnatomyReview of Anatomy

Types of MusclesTypes of Muscles

– Smooth: blood vessels and Smooth: blood vessels and organsorgans

– Cardiac: heartCardiac: heart

– Skeletal: muscles Skeletal: muscles

for movementfor movement

Review of AnatomyReview of Anatomy

Skeletal Skeletal MuscleMuscle

– 600 Skeletal 600 Skeletal MusclesMuscles

– Voluntary Voluntary MovementMovement

– Origin / Origin / InsertionInsertion

– 75% H2O, 75% H2O, 20% Prot.20% Prot.

The Structure of The Structure of Skeletal MuscleSkeletal Muscle

EpimysiumEpimysium– Covers the entire muscleCovers the entire muscle

PerimysiumPerimysium– Covers the FasciculiCovers the Fasciculi

EndomysiumEndomysium– Covers the muscle fiberCovers the muscle fiber

SarcoplasmSarcoplasm– Surrounds the myofibrilSurrounds the myofibril

The Structure of a The Structure of a Muscle CellMuscle Cell

SarcoplasmSarcoplasm– Transverse TubulesTransverse Tubules– Sarcoplasmic ReticulumSarcoplasmic Reticulum

MyofibrilMyofibril– SarcomereSarcomere

Myosin (heads)Myosin (heads)

Actin (tropomyosin, troponin)Actin (tropomyosin, troponin)

The Sliding Filament The Sliding Filament TheoryTheory

Motor nerve impulseMotor nerve impulse– motor nerve releases ACh to motor nerve releases ACh to

sarcolemmasarcolemma

Depolorization causes chain Depolorization causes chain reactionreaction– sarcoplasmic reticulum releases sarcoplasmic reticulum releases

calciumcalcium– calcium binds with troponin calcium binds with troponin – troponin lifts tropomyosintroponin lifts tropomyosin– myosin heads bind with actin (cross myosin heads bind with actin (cross

bridge)bridge)

Power Stroke: is the tilting of the Power Stroke: is the tilting of the myosin head myosin head

The Sliding Filament The Sliding Filament TheoryTheory

Energy is required for muscle Energy is required for muscle actionaction– the myosin head binds to ATP, and ATPase the myosin head binds to ATP, and ATPase

found on the head splits ATP into ADP and P, found on the head splits ATP into ADP and P, releasing energy for muscle contraction.releasing energy for muscle contraction.

Calcium releases for muscle Calcium releases for muscle relaxationrelaxation– calcium is pumped out of the sarcoplasm and calcium is pumped out of the sarcoplasm and

back into the sarcoplasmic reticulum for back into the sarcoplasmic reticulum for storage, which requires ATP.storage, which requires ATP.

Slow Twitch vs Fast Slow Twitch vs Fast TwitchTwitch

SToSTo

slow ATPaseslow ATPase

small SRsmall SR

small motor small motor neuronneuron

less fibers per less fibers per unitunit

aerobic aerobic enduranceendurance

red color - red color - capillariescapillaries

B oxidation B oxidation enzymesenzymes

FTa, FTb, FTcFTa, FTb, FTc

fast ATPasefast ATPase

large SRlarge SR

large motor large motor neuronneuron

more fibers per more fibers per unitunit

anaerobic anaerobic powerpower

pink or white in pink or white in colorcolor

glycolytic glycolytic enzymesenzymes

Muscle Fiber Muscle Fiber RecruitmentRecruitment

Motor units: Motor units: consists of a single motor consists of a single motor neuron and all of the muscle fibers is supplies.neuron and all of the muscle fibers is supplies.

All-or-None Response: All-or-None Response:

Gradation of recruitmentGradation of recruitment– force production: force production: is due to the number is due to the number

of fibers recruited, not the force generated by of fibers recruited, not the force generated by each fibereach fiber

– conditioning response: conditioning response: training training effects the coordination and recruitment of effects the coordination and recruitment of muscles for specific activitiesmuscles for specific activities

FTb & FTc fibers aren’t easily FTb & FTc fibers aren’t easily recruitedrecruited

Generation of ForceGeneration of Force

number of number of motor unitmotor unit

types of motor types of motor unitsunits

size of the size of the musclemuscle

muscles initial muscles initial lengthlength

angle of the angle of the jointjoint

muscle’s speedmuscle’s speed

stretch reflexstretch reflex

Use of MusclesUse of Muscles

Types of Types of MovementMovement

– agonistsagonists

– antagonistsantagonists

– synergistssynergists

Types of Types of ContractionContraction

– concentricconcentric

– staticstatic

– eccentriceccentric

Requirements For Requirements For Large Muscle Large Muscle DevelopmentDevelopment

Proper NutritionProper Nutrition– 65% CHO, 20% Fat, 15% 65% CHO, 20% Fat, 15%

ProteinProtein

Resistance TrainingResistance Training

GeneticsGenetics

Hormonal Secretion LevelsHormonal Secretion Levels– testosteronetestosterone– androgensandrogens

ACSM Strength ACSM Strength GuidelinesGuidelines

FFrequency = 2-3 days/weekrequency = 2-3 days/week

IIntensity ntensity – 85% of max for strength85% of max for strength– 75% of max for muscular power + 75% of max for muscular power +

(method)(method)– 50% - 65% of max for muscular 50% - 65% of max for muscular

enduranceendurance

TTime = ime = – 30 - 90 sec. per set / 8 - 12 reps 30 - 90 sec. per set / 8 - 12 reps

per setper set– work to rest ratio 1:4work to rest ratio 1:4

SSpecificity = resistance typepecificity = resistance type

Strength Training MythsStrength Training Myths

Strength training will cause “muscle Strength training will cause “muscle boundness”boundness”

Women who strength train will Women who strength train will become masculinizedbecome masculinized

Strength training reduces speedStrength training reduces speed

““No pain - No gain”No pain - No gain”

It takes hours of daily training to gain It takes hours of daily training to gain muscle massmuscle mass

Food supplements will speed up Food supplements will speed up muscle developmentmuscle development

Anabolic steroids are safe and Anabolic steroids are safe and effectiveeffective

Amino Acids are safe and effective Amino Acids are safe and effective

Types of TrainingTypes of Training

IsometricIsometric

IsotonicIsotonic

IsokineticIsokinetic

PlyometricsPlyometrics

Modes of TrainingModes of Training

Free weightsFree weights

NautilusNautilus

HydraulicsHydraulics

FrictionFriction

Rubber tubingRubber tubing

CybexCybex

Bow-flexBow-flex

Box-jumpsBox-jumps

HydrotherapyHydrotherapy

Etc.Etc.