How many muscles are in an arm?

Answer 1

The muscles usually work under the the 'all or non law'.Once when your arm is in action all the muscles involved in the shoulder complex works namely,abductors,adductors,rotator cuff,forearm,core etc.And it also depends on which plane you are moving your arms.If it is in the Sagital plane then your working your upper pecs and anterior delts.When you work in the frontal plane, you work lateral delts,lats,supraspinatus etc.The muscles which I mentioned are agonists and stabilizers, and their antagonist counter-parts to play significant role in bringing back your arms down by slowing down the reverse action.And to your surprise your core is the power house to generate the power to lift your arms out.This is prominantly seen with the resisted lifts.But the core gets the energy to provide for the shoulder complex from the legs which work against the ground and utilizes the reaction from the ground efficiently.This is how the kinetic chain works in an individual to incorporate a single simple action.This kinetic chain is fully used by trained persons to do some actions and the wrong way of handling it over years and years end up in strains followed by injuries at different joints....To be simple for your question all the muscles work when you lift your arms!

Answer 2

There are two main muscle groups in the human arm. These muscles are the biceps and the triceps. In order for the arm to extend or retract both of these muscles are put to work.

Answer 3

all of them

Answer 4

It really depends on how you do it.

Answer 5

there are 20 muscles in your arm : )

Answer 6

Extensor digitorum is the prime mover

Answer 7

4