Practice Tai Chi well, or you will hurt your knee. Of course, for ordinary people, it is no problem to practice several times a day, but for Tai Chi masters and Tai Chi athletes, practicing dozens of times a day or even tens of thousands of times a year is easy to damage their knees, so practicing martial arts costs a price. For ordinary people, as long as they practice boxing moderately and do warm-up activities before practice, it is basically harmless to their health.