Asami Chiba

Asami Chiba (千葉 麻美, Chiba Asami; born 25 September 1985), or Tanno, is a Japanese sprinter who specialises in the 400 metres. She is the Japanese record holder in the event, and has also broken the national record in the 4×400 metres relay on multiple occasions. She is a member of Natureal Athlete Club in Japan and is coached by Kazuhisa Kawamoto.

As a junior athlete, Tanno won two silver medals at the Asian Junior Athletics Championships, setting a national record in 2004, and she also reached the final of the World Junior Championships. She competed at her first World Championships the following year and won two bronze medals at the Asian Championships. In the 2006 and 2007 seasons, she won bronze at the 2006 Asian Games and two silver medals at the Asian Championships. She also helped set a new national relay record and became Japan's first ever female sprint semi-finalist at the 2007 World Championships. She was less successful at the 2008 Beijing Olympics and 2009 World Championships as she was eliminated in the heats at both events.

A five-time national champion in the 400 m, she has only lost once in the event at the Japanese championships, to Satomi Kubokura. She mainly competes on the Japanese athletics circuit, running at the Osaka Grand Prix, Shizuoka International and the Super Meet in Kawasaki.