Generally speaking, people can do some sports a week after the cataract surgery. But for the sake of your eye safety, you had better take some mild sports such as going for a walk rather than doing ball games. Playing tennis may sometimes requires you to jump and flip, which needs a lot of energy. It is dangerous because your iris may get falling out due to the fierce sports, then you have to go to the doctor's for another surgery. Therefore, you had better not play tennis, instead, you can do some walking, play some chess games, and do on.
Generally speaking, you should avoid strenuous activity within 3-6 months after cataract surgery. Even the eye exercises and eyeball massage action after the operation is better not carried out. The more details include: 1. a week after operation of any larger amounts of physical activity are prohibited except slow walk. 2. one month after surgery you had better rest as much as possible, dirty water or soap should be avoided spilling in the eye, so as to avoid infection. 3. do not put any pressure on eyes ( including rubbing eyes, blinking, and so on ), and prevent the injuries of eyes. And if you want to do some sports, seek the views of the eye doctor first.