Non-standard movements are easy to be uneven. For example, it is possible that you have different amplitudes on both sides, so that one side is strong in exercise and the other side is slightly weak, which will form muscles of different sizes. As for the right arm is stronger than the left arm, this is normal, as long as you are not left-handed, that's it. Over time, the use of the right arm will become stronger!

You may say that the left chest muscle is big but weak, but when you use your arm (lifting things and pulling things), you need the strength of the arm muscle ... and there are quality problems. The left pectoral muscle is big, but the muscle is weak. The right pectoral muscle is "strong", strong (just like two people, one is strong and the other is puffy, who is strong? )

The correction is simple. Arm strength exercises the left arm to increase the degree until it is equal to the right arm. In order to balance the left and right chest muscles, you can reduce the exercise of chest muscles in the recent period (for example, supine birds, only do the right side ...), but I suggest that you do it with one hand, fast on the left and slow on the right (for example, supine birds, once on the left 1 second, once on the right for 3 seconds ...), so that the left chest muscles will be more "solid" and the right chest muscles will be more "solid". ......