This is goalball, a sport designed for people who can't see. It was invented in 1946 to help blinded war veterans. But even people who aren't visually impaired can play because everyone wears goggles that completely block out their sight. This puts everyone on a level playing field.
Goalball players can't see the ball, but they can hear it because it has bells inside. 3 competitors on each team line themselves up along tape-covered ropes that serve as tactile markers for the court. The object of the game is to get the ball inside the opposing side's goal.
This video shows a 2011 competition between the national teams of Germany and Japan.