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Flexor muscles vs Extensor muscles

hello there so today I'm all dressed up

because I'm going to be explaining

muscles I'm also three goats in one

basketball goat the football goat and

the teaching goat jokes aside your body

can perform quite a complex set of

movements but the ones we're going to

focus on today are the ones that happen

at joints you know joints like the elbow

joint in the leg is the knee or the foot

the joint is the angle the rear body

performs two types of movements atoms

which are bending and extending or in

better terms flexion which is bending

and extension flexion extension flexion

extension in the leg flexion bending

extension flexion extension flexion

extension for the hood flexion you bring

in your toes closer to your leg like

this as if you're standing on your heels

and extension would be extending your

leg like this standing on your tiptoes

so this is flexion extension flexion

extension so just in case you weren't

paying attention you're just staring at

my muscles

let's make sure that you understood what

I said the basic movements across joints

are flexion when you bend your appendage

your arm your leg or your foot and

extension when you extend that appendage

so this is extension and this is flexion

and this is extension here of the leg

and flexion of the leg right so now

let's focus on the muscles which are

performing these movies so one thing

that you need to keep in mind the muscle

on the side of the movement is actually

the one involved in performing it so

let's start with flexion first of all

what I'm talking about my mom when I

flex my arms like this so I'm bending

across this point in this direction the

muscle involved in this movement should

be the one on this side so it's the

biceps so this muscle

is actually the flexible for the leg

flexion is in this direction so the

muscle performing this movement is

actually the one in the back the

hamstring which is in this case the

flexor muscles sometimes they call it

the biceps femoris so this muscle in the

back is actually deflections flexion in

the foot again I'm bringing my toes

closer to the lab so the muscle

performing the action is the one on this

side which is the flexor in this case

it's called the tibialis anterior or the

anterior to be us so this is the flexor

muscle right here you can actually sense

and feel its contraction when you're

bending north again let's make sure that

you got it flexors are the muscles

responsible for flexion so for the leg

the flexor is actually the one at the

bottom here the hamstring when it

contracts will become shorter and your

leg will be pulled in this direction so

the leg will then so in this way

election election and flexion now the

same thing for your foot the muscle

perform the the contraction or the

activity or the function as in the front

the flexor is called the tibialis

anterior at the beginning here it's

relaxed it's longer than Turner when it

contracts it will pull the foot upwards

in this direction so like so again again

now returning to the arm when I'm

extending my arm like so so the movement

is in this direction backwards the

muscle involved should be the one in the

back which is this muscle the triceps so

the triceps is actually the extensors

the flexor is device ups which flexes

the arm the extensor is the triceps

which extends the arm for the leg again

when I extend my leg the direction of

movement is to the front so the muscle

performing this movement is actually

this one one in the front the quadriceps

so this is the extensors the one in the

back is the flexor

the one in the front is the extensor

flexion

extension or deferred again extension

would be in this way if you're standing

on your tiptoes so the muscle performing

the action is the one in the back on the

side of the movement so this is actually

the extensors labeled occasion the

doctor of the leg or equality triceps to

earth so this is the extension alright

again repeating the same idea just to

make it clear so extensors are the

muscles that are responsible for the

extension of your leg foot or whatever

so for the leg the extensor muscle is

the quadriceps located here when this

muscle contracts it will pull your leg

up loads in this way and again and again

for the foot the extensor muscle is the

tricep surah a group of two muscles

located here in it's a Miele bata of

course it's not called the duck of the

lake I was joking

when it contracts the foot is extended

in this way and again and again your

muscles actually pass in two states they

are either contracted or they relaxed

when they are contracted the initiate

Dean they become shorter and thicker

because they are pulling your body parts

closer together and when they relaxed

they become what softer and longer now

remember both the flexor and extensor

muscle pass through these two states

when I do my mom like this the flexor is

contracted the extensors is relaxed when

I extend my arm now the extensors is

contracted the flexor is relaxed so

don't confuse flexion with contraction

and expansion with relaxation both the

flexor and the extensor can contract or

relax depending on the movement that you

do if you are flexing or extending okay

so now we establish that we have two

types of muscles working across the

joint and they actually have opposite

functions we have the flexors which flex

or bender

parks your arms your legs or feet and we

have the extensors which extended so now

let's think about the function or the

status of each muscle during each

movement so let's start with the arm

again when I flex my arm obviously the

flexor as we said the biceps is

contracted what about the extensive the

opposite muscle at this time miss from

the triceps at this particular moment

the extensors should be inactivated for

what reason

because both muscles are pulling in

their directions my arm was still simply

sticking that in the middle or it would

be like a tug-of-war the one pulling the

most will win so what I want to flex I'm

letting the flexor and extensor is being

relaxed what I'm doing the opposite the

opposite is actually happening now the

extensor is contracted the triceps in

this case and the flexor is relaxed

so these are cooled and techni stick

muscles meaning they work opposite to

each other when one contracts the other

relaxes the same thing for the leg when

I flex my leg the flexor is working when

I extend the extensor is working when I

flex the flexor has to contract at the

same time the extensor has to relax and

when I extend the opposite happens

the extensor contracts and the flexor

relaxes so they are antagonistic muscles

also for the foot now the alternating

movements will be flexion extension

flexion extension when I flex the flexor

muscle the tibialis anterior contracts

at the same time the extensors the

triceps una rata is relaxed when I

extend my foot the opposite happens now

the extensor the triceps works

contracted the flexor is relaxed again

antagonistic muscles okay so the flexor

and extensor muscles qualify as

antagonistic muscles meaning that they

have opposite functions and when one is

active or contract the

other is relatively inactive or is

relaxed so let's take a closer look at

that here on the leg the antagonistic

muscles this is the flex the extensors

again this is the flexor when we extend

our leg

the extensor is contracted the flexor is

relaxed when we do the opposite now the

flexor is contracted and the extensor as

it lacks again and again they are all

working in opposite manners and for the

foot the same idea this is in the back

the extensors the triceps surah and this

is the flexor the tibialis anterior when

we extend our foot this is contracted it

becomes thicker and shorter this is

relaxed when we do with the opposite

what happened now this is contracted the

flexor is contracted and the extensor is

relaxed so they are working opposite to

each other they are antagonistic muscles

this is the summary of the movements in

the leg and the foot so we have in the

leg the extensor is the quadriceps the

flexor is the hamstring or the biceps

femoris during flexion this is the

movement here the flexor is contracted

well as the extensor is relaxed whereas

during extension the flexor is relaxed

and the extensor is now contracted the

same thing for the foot

the extensor is the triceps or on the

back the flexor is the tibialis anterior

and the front during flexion the flexor

contracts the extensors relaxes and

during extension the flexor is relaxed

and the extensor is contracted study the

activity of these muscles when we're

working in alternating meaning I'm

starting to do so I'm going to flex my

arm then extend flex more arm

flexor is working finally an application

exercise so in your books they say using

a knee exhale

Oh which is French for experimentation

assist a parlour coordinator or a

computer assisted experiment when an

error on the sound of computers blah

blah

so they're saying we can simultaneously

record the activity of both muscles of

the leg the tricep surah in the back

extensors and it's BLS anterior this one

here the flexor during alternative

voluntary movements of flexion and

extension of the foot so the person here

is moving his foot from flexion to

extension and an alternating method and

they are recording the activity of both

muscles here the one on the top is for

the triceps surah and on the bottom is

for DTR Santillan association so your

task is to show from the experiment that

the triceps surah and the tibialis

anterior or antagonist

that's all guys I hope you enjoyed the

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