What are some effective ways to overcome attention disorders?

Studying for a Ph.D. and currently writing a thesis. Trying the Pomodoro Technique. Not to mention how effective this method is. A by-product is that I keep track of exactly when I was focused. I found that I was very tired after working for 3 hours a day. Then I checked online and saw that some PhD students also said that three hours a day is a good result. The key is persistence. The length of attention span varies from person to person. If you can no longer concentrate, you have reached your limit. Rest is important to increase productivity. Otherwise, why would the strong teams in football and basketball lose? Double matches a week and back-to-back games are very relevant. There are many types of rest, including sleeping, meditating, and playing Dota. You must know that it is difficult to fall asleep when the brain is working at high speed. The best way is to do some exercise to transfer stress from the mind to the body, which will also help you sleep at night. Of course, my personal favorite is to turn on the computer, play a mindless game, and then open an American TV series or something next to it.