Let others explain some biological theories to you.
It is suggested that you should fully warm up before practicing strength, and the intensity will gradually increase. At first, don't do much.
Actions should be grouped and there should be a moderate rest in the middle. After the strength is enhanced, you can add 1 group or several groups every once in a while, and the rest cannot be reduced.
After the fitness, you should relax and tidy up before you have a rest.