Because muscles can not push, they can only pull (contract). So while your biceps contract to pull the arm up into a flexed position; the triceps are necessary to pull the arm back down into an extended position. Skeletal muscles or groups of skeletal muscles must work in pairs. These pairs are called "antagonistic" muscles; while one group is contracting, the other group is relaxing.
You can easily feel this action in your arm. With your right arm extended, place you left hand on your right biceps. Flex your arm (as if to make a big muscle) and you will feel the biceps brachii tighten and bulge somewhat; we are familiar with this. Now, place your left hand on your triceps and straighten the right arm completely (extra straight) and you should be able to feel the triceps brachii tighten. Although aided by gravity, the triceps MUST contract to straighten the arm.
because they want to dumb head
is this true?? i think it is really stupid..
The biceps and triceps are used to bend and extend the elbow. When your biceps contract it bends the elbow and when the triceps contract it extends the elbow. Also, when the biceps contracts, the triceps relaxes - and vice versa.
No. Try and feel. Only triceps is contracted, biceps bend the arm over the elbow joint.
1 of each on each arm. Triceps are in the back of the upper arm while the Biceps are in the front. Both of which run from your shoulder to elbow.
A bad guy if you are talking about human characters in a story. But if you are talking about muscles, it is the one that acts to oppose the action of the prime mover, or agonist. For example: The biceps and triceps have an agonsit/antagonist relationship. When you flex your elbow (pretend you are Arnold Schwarzenegger and you want to 'bulge you biceps'). When you do that your triceps relaxes to allow the biceps to contract. But, in actuality, both are contracting, only the biceps are getting shorter and the triceps are getting longer. In other words, if you did not have the triceps to control and mitigate the movement of the biceps, you'd end up punching yourself in the face because there was no way to control the biceps shortening and flexing the elbow until you KO'd yourself. In other words, the agonist, or prime mover is the gas pedal and the antagonist is like the brakes. You need them both to control movement in the body.
Flexion (same as bending) at the elbow joint (between the humerus and the radius and ulna) is mainly achieved by the Brachialis Muscle. This is not the answer most would expect as everyone knows the Biceps Brachii (Biceps of the arm) are what flexes this joint. In fact the biceps does both supination and flexion of the elbow because its insertion is on the radius. Only when the forearm is supinated, the biceps is able to assist the deeper and more powerful brachialis muscle with the flexion of the elbow.
It's usually used when you push or lift an object. According to the movement of the arm, when you are exercising or working, you may use the biceps, the triceps, or both.
The triceps and the brachialis both attach to the ulna.
when the arm is straightened, the triceps are used. when the arm is bent, the biceps are used. if you tense both the tricep and biceo at the smae time, the arm will be unable to move (bend or straighten). when pulling or lifting, the biceps are used, not the triceps.
When your arm is bent, your biceps flex and your triceps relax. When your arm is straight, your biceps relax and your triceps flex. This opposing set of muscles allows you to push and pull things efficiently.
Above it (it's under the biceps).The humerus is proximal to the elbow.
Agonistmuscles cause a movement to occur through their own contraction. [1] For example, the triceps brachii does during the up phase of a push-up (elbow extension). During the down phase of a push-up, the same triceps brachii actively controls elbow flexion while relaxing. It is still the agonist. While resisting gravity during relaxing, the triceps brachii is still the prime mover, or controller, of the joint action. For both of those movements the elbow flexor muscles are the antagonists. Agonists are also referred to, interchangeably, as "prime movers", since they are the muscles being considered that are primarily responsible for generating a specific movement. This term typically describes skeletal muscles.[2]
to flex the forearm at the elbow, you use the biceps brachii, brachialis, and brachioradial (to a lesser extent).to supinate the forearm, you use the biceps brachii and the supinator muscles.the biceps brachii does both motions.