Most people's left and right limbs are unbalanced, which is due to habit problems (most people are right-handed and generally have more developed right arms). This is a very normal phenomenon. But the gap should not be too big, otherwise it will affect the balance of muscles and affect health.

It is obvious from the picture that your left and right upper limbs are obviously unbalanced, and your right arm is much more developed than your left arm.

Biceps biceps brachii has two heads, a long head and a short head. Where the white line is drawn is the short head of biceps brachii. When doing dumbbell bending, the muscles in the white circle are often hard. This is because your left arm is obviously weaker than your right arm. Don't worry too much. Pay attention to control the correctness of centrifugal contraction and movements during training, and don't do some high-risk movements.

I suggest you do more isolation training, that is, practice your left and right limbs separately, such as using dumbbells or steel wires. When training large muscle groups (such as pull-ups, narrow strokes, etc.). ), try to concentrate on the left side and let the left muscle group participate more.

Let me tell you a little detail. When doing biceps brachii training (such as dumbbell bending), try to hold the dumbbell with your ring finger and little finger. Feel it yourself slowly, and you will find the difference.