KINGSTON (Reuters) - Six-time Olympic champion Usain Bolt has already started his preparations for next year's Rio Games and has sent a warning to his competitors.

He thinks he is capable of breaking 19 seconds in the 200 metres.

Bolt's record of 19.19 seconds has stood since Aug 20, 2009, four days after he set the 100m record of 9.58 seconds, both at the world athletics championships in Berlin.

"I really want to run under 19 seconds," Bolt said from his training base at the University of West Indies in Kingston.

"I think it's one of the toughest ones because it's going to be hard to find the right day and sometime the perfect race to get this (200m record).

"It will not be an easy task but I personally feel I can do it and my coach (Glen Mills) thinks I can do it so it is just about the work and finding the perfect time to do it, so it is one of the things (for 2016)."

Bolt is seeking to become the first man to win three successive Olympic titles in the sprint events and the 4x100m relay in Rio.

The lanky Jamaican shrugged off a nagging pelvic injury this year to win three golds at the Beijing world championships in August.