<P> Another example is the dumbbell curl at the elbow . The `` elbow flexor '' group is the agonist , shortening during the lifting phase ( elbow flexion ) . During the lowering phase the `` elbow flexor '' muscles lengthen , remaining the agonists because they are controlling the load and the movement ( elbow extension ) . For both the lifting and lowering phase , the `` elbow extensor '' muscles are the antagonists ( see below ) . They lengthen during the dumbbell lifting phase and shorten during the dumbbell lowering phase . Here it is important to understand that it is common practice to give a name to a muscle group ( e.g. elbow flexors ) based on the joint action they produce during a shortening ( concentric ) contraction . However , this naming convention does not mean they are only agonists during shortening . This term typically describes the function of skeletal muscles . </P>
<P> Another example is the dumbbell curl at the elbow . The `` elbow flexor '' group is the agonist , shortening during the lifting phase ( elbow flexion ) . During the lowering phase the `` elbow flexor '' muscles lengthen , remaining the agonists because they are controlling the load and the movement ( elbow extension ) . For both the lifting and lowering phase , the `` elbow extensor '' muscles are the antagonists ( see below ) . They lengthen during the dumbbell lifting phase and shorten during the dumbbell lowering phase . Here it is important to understand that it is common practice to give a name to a muscle group ( e.g. elbow flexors ) based on the joint action they produce during a shortening ( concentric ) contraction . However , this naming convention does not mean they are only agonists during shortening . This term typically describes the function of skeletal muscles . </P>
which muscle is considered the primary agonist of elbow extension
which muscle is considered the primary agonist of elbow extension
The `` elbow flexor '' group
The `` elbow flexor '' group