Do you still need to continue practicing if your fitness arm is sore at the bend?

This is a normal reaction. If the muscles don't feel sore, it only means that you don't stimulate the muscles enough, and the fitness effect will be greatly reduced. My advice to you is to take a day off and exercise the next day. When your muscles get used to this kind of intense stimulation, you won't feel obvious pain. You need to add a lot at this time.

So sour, you can get used to adding a lot of muscle. Keep trying.