Brachialis Taking Over?

[theoath]

I am left handed. I do regular dumbell curls (palm up). In the left arm, I am seeing results in the biceps brachii; it gets bigger and stronger. However, when I do the same bicep curls with my right (same form and reps), I feel the brachialis muscle doing all the work. The brachialis on the right is noticibly bigger and stronger than the brachiallis on the right. When I flex my left arm, I feel mostly the bicep s brachii tightening and working. When I flex my right, I can feel almost nothing in my biceps brachii, but the brachiallis tightens and tenses.

Because my left is my dominant arm, it is naturally stronger. However, the right brachialis is still considerably bigger and perhaps stronger than my left brachialis.

Whenever I do bicep curls with the palm up with the left hand, my biceps brachii feel worked afterwards. When I do hammer curls with the left, the brachialis feels worked.

However, when I do both a regular curl or a hammer curl, with my right, I only feel the brachialis working. And afterwards, the brachialis is tight and hard, and the biceps brachii feel like they did little or no work.

When I do any sort of curlng movement with my right arm, the brachialis tightens. It is a lot denser than my biceps brachii, and tenses very easily. I do boxing and martial arts, and having this very easily tensed muscle is not good.

I know its impossible to completely isolate a muscle, but does anyone have any ideas or have a similar issue?

 

[Diablo1990]

When I flex my left arm it is hard to feel the bicep tighten unlike my right arm which is my dominant arm I feel it tightening. I can curl the same amount of weight on each arm

 

[theoath]

The thing here is, I DO feel my muscles tightening in my right, just that it's the brachailis instead of the biceps. It has gotten to the point where it is dominant over the biceps brachii..