Roman Sludnov has become the first person to swim the 100-metre breaststroke in under a minute.

And in breaking the barrier the Russian swimmer broke a record he had set at the national championships in Moscow only 24 hours earlier.

"It hasn't hit me yet," Sludnov said afterwards.

"Maybe in a couple of hours or a couple of days I will understand what I have done," he added.

The 21-year-old, a student from the Siberian city of Omsk, clocked 59.97 seconds in the final to better his own record of one minute 0.26 seconds, which he swam on Thursday.

His initial effort beat Ed Moses' record which was set in Austin, Texas on 29 March this year by 0.03 seconds.

In his second record swim, in the final, Sludnov opened up much faster than in his semi-final, touching the halfway mark in 28.54 seconds.

"We saw a big improvement in his opening 50 metres," said his coach and mother Natalya Roshchina.

"He executed everything right from start to finish and this was a perfect swim."

Sludnov is planning to take part in the 100-metre and 50-metre breaststroke events at the World Championships in Fukuoka.