How are the players of the red and blue teams of the national men's basketball team distributed?

Duan Lian, Minister of Security of chinese basketball association National Team, said in an interview: "This year, the national training team implemented the head coach responsibility system. The names of the athletes of the two men's basketball training teams were studied by two head coaches at a meeting and selected fairly by on-site lottery. Other members of the coaching staff are also recommended by the head coach. Players from the red and blue teams will be divided into two groups. After a stage of investigation, the number of red and blue teams will remain at around 15. "