Martial arts
It is difficult to compare the effectiveness of the different existing arts. Recently, people developed competitions like the Ultimate Fighting Championship in the United States of America or Pancrase in Japan. That competitions also are known as "mixed martial arts" or MMA. But these competitions only test the fighting styles in limited situations (fighting against an experts, only fighting one opponent, fighting while wearing the right clothes - none of which would be true in other situations such as self-defense).