If the arm hits the left shoulder joint hard, will it hurt or itch? Does this affect fitness?

This sound is caused by lack of exercise for a long time and insufficient lubrication of joint cavity. It doesn't matter if you live a normal life. However, when you exercise vigorously, it will be affected. It is suggested to increase the exercise of relevant parts appropriately.

It is good for your health to insist on doing some small amount of aerobic exercise at ordinary times.