Judo became an Olympic sport in the 1964 Tokyo Games and was dominated by the country of its origin until the 2008 Games in Beijing.

This summer in London, Japan's men failed to win a single gold medal in judo and its women claimed just one. It was the first time since judo's Olympic debut that the men failed to grab gold.

Have Japan's judoka become weaker or have those in other countries gotten stronger? Here are some questions and answers: