the muscular system

Cindy Quisenberry

The Muscular System

What is the major function of the muscles?

Movement – walking, running, etc.Digest FoodPumps blood throughout your bodyProvide stabilityMovement of substances (ie: urine)Help control body temperature

Functions of the Muscles

Provide movementHelp maintain postureProtect internal organsProduce heat and energy for the body

Skeletal Muscles

Muscle Types

Voluntary - muscles can be contracted at willSkeletal – helps us get through our environment

safely and successfully

Involuntary - muscles govern movement that is not controlled by will, such as respiration and digestion. Cardiac – responsible for pumping blood through

little tubes known as blood vessels

Smooth – responsible for filling and emptying blood vessels and all hollow organs, plus they control the movement of air through the bronchi tubes.

Muscle Types

MusclesLigamentsTendons

Movement takes place at the joint and uses the:

a sac lined with a synovial membrane that helps the movement of joints

Bursa

Keep in mind that voluntary movement requires three main systemsSkeletalMuscularNervous

Skeletal Muscles:

Rule #1Muscles must have at least 2 attachmentsMuscles must cross at least one joint

Rule #2To produce movement, muscles ALWAYS pull

and get shorter.

Which attachment is moving to the other? Is the proximal attachment moving to the distal or is the distal moving to the proximal?

Muscle Rules:

The attachment that remains in its “original” position is known as the ORIGIN. This attachment anchors the muscle.

The distal attachment (the one that is moving) is the INSERTION.

Muscle Rules:

Muscle cell = Muscle fiberCan one muscle fiber be strong enough to pull

on the wrist and bring it up?Fascicle - “TEAM Fascicle”

Muscle fibers with buddiesCan generate more pull

Connective Tissue – Fascicle needs connective tissue support so that is can work together more efficientlyPerimysium – Peri = ?

Spaghetti:

Find:The two attachments of the fascicleNotice that the muscle cells are ALWAYS

pointing to the attachmentsNotice how you can still see the muscle fibers

through the Connective Tissue (CT)

Spaghetti:

Rule #3Muscles fibers or “striations”

ALWAYS POINT to their attachments and show the direction of pull.

Muscle Rules:

Even though one fascicle can pull on the attachment, one “team fascicle” cannot produce a tremendous amount of force. There needs to be many teams working together to get force and power to maintain stability in joints and forceful movements.

Epimysium – connective tissue that hold a bunch of fascicles together

Spaghetti:

Belly of the Muscle:

TendonDense Regular CT

Belly

Belly of the Muscle:

TendonDense Regular CT

Belly

Epimysium – epi = ?, myo = ?Sometimes also called Fascia = Epimysium

Fascicle – covered by Perimysium

Muscle Fibercovered by EndomysiumEndo = ?

Rule #1Muscles must have at least two attachments

cross at least one joint.

Rule #2Muscles can only “pull” and get shorter.

Rule #3Muscles fibers or “striations” ALWAYS POINT

to their attachments and show the direction of pull.

Muscle Rules:

Ventral Ventral Side of the ForearmWhen a muscle moves ventral to ventral it is

a FLEXOR! (The angle between the ventral sides is decreased)

Show placement for flexor of the forearm.

Place attachments for flexor of the hip.

Identification of Muscle Movement & Location:

Because muscles can only pull, how can you get your wrist back from flexion?

Show me where would you place your left hand muscles to do this?

Identification of Muscle Movement & Location:

DorsalMuscles that move the dorsal side

towards the dorsal side are know as EXTENSORS!

Identification of Muscle Movement & Location:

V is for Ventral (peace sign on chest)Ventral side will be lighter then the

Dorsal side This is the theme throughout the animal

kingdom.Reach and touch the back of your neck.

This is the Dorsal side. The back of your torso and arms are the

Dorsal side (darker side).

Identification of Muscle Movement & Location:

What about the legs?The Ventral/Dorsal relationship is about

movement and not based on the standard Anatomical Position – the legs are special.

Identification of Muscle Movement & Location:

Frog Position Stand up and turn your knees and toes

outwardPlace your hands on the inside of your

legs, now become a biped by rotating your knees and toes inward.

Your hands rotate towards the back . . . So the Ventral side rotates back when you become a biped.

Identification of Muscle Movement & Location:

Frog Position Stand up and turn your knees and toes

outwardPlace your hands on the outside of your

legs, rotate your legs back in and notice how your hands rotate to the front.

This is the Dorsal side rotating to the front . . . So the Dorsal side rotates forward when you become a biped.

Identification of Muscle Movement & Location:

SummaryThe Ventral side rotates to the back at the

hips and the dorsal side is rotated to the front.

Place your right hand on your chest and your left hand on the back of your left leg.These areas are the VENTRAL side of the body!Ventral side has FLEXORS only.

Dorsal side is where EXTENSORS are located!

Fetal position is FLEXION! (Flexion is the ventral side of the body.)

Identification of Muscle Movement & Location:

Anatomical Position – not about movement

Arms are positioned to have the thumbs outward (pointing lateral/outward)

Anterior & Posterior

Ventral & Dorsal

Hip FlexionHip ExtensionDorsiflexion (extension)Plantar Flexion

Identification of Muscle Movement & Location:

If a muscle can flex (ventral location) a joint, then there is an opposite muscle on the other side that extends the joint (dorsal location).

If there is a muscle that rotates a joint one way, then there has to be a muscle on the opposite side that will rotate the muscle back (ie: supinator rotates the palm up and pronator rotates the palm down)

Muscles work in opposing pairs

What does the name tell us?If the name of a bone or regional

area of the body is used in the first part of the muscles name or is the muscle’s name, THAT IS THE MUSCLE’S ORIGIN!

Muscle Names

Example:Sternocleidomastoid Sterno = sternum and the Cleido = clavicle

(origins)Mastoid = mastoid process of the temporal

bone (insertion)This muscle gives its attachments.

Muscle Names

Sometimes muscles are named after their job.Flexor Pollicus Longus tells that the muscle

flexes the thumb (it is on the ventral side of the body and it is a flexor)

Sometimes muscles are named by their shape or location in the body.Rhomboid muscles are rhomboid shape and

Tibialis anterior tells us that the muscle is located on the front of the tibia.

Muscle Names

What is the major function of the muscles?

Movement – walking, running, etc.Digest FoodPumps blood throughout your bodyProvide stabilityMovement of substances (ie: urine –

urinary sphincter)Help control body temperature

Main Functions of the Muscles

Provide movementHelp maintain postureProtect internal organsProduce heat and energy for the body

Skeletal Muscles

a sac lined with a synovial membrane that helps the movement of joints

Bursa

MusclesLigamentsTendons

Movement takes place at the joint and uses the:

.

Review

___________________ are involuntary muscles.

Muscles that act on the lining of the body’s passageways and the hollow internal organs

A type of striated muscle that forms the wall of the heart .

______________________ is involuntary and is responsible for the contraction of your heart. Your heart beats 100,000 times each day.

Muscles attached to bone that cause body movements

Most of your muscle tissue is skeletal, and almost all _________________ are under voluntary control.

Tendons – anchor muscles to boneBursas – lie between some tendons

and the bones beneath them. Bursas are lined with synovial fluid – making it easier for the tendon to slide over a bone when the tendon shortens

Musculoskeletal Structure

What would the term be for inflammation of the bursa?

What would the term be for inflammation of a tendon?

Musculoskeletal Structure

What Muscles Do

Skeletal muscles work in pairs to produce movement.

Caring for Your Muscles

Warm up properly and stretch before exercising, and cool down after exercising to prevent injury.

Use proper equipment and wear appropriate clothing to protect muscles during any physical activity.

Practice good posture to strengthen back muscles.

Eat high protein foods to build muscle.

Get regular exercise.