Both Kiera Aitken and Ronald Cowen have broken national records at the World Swimming Championships in Barcelona.

Aitken's time of 1:06.07 in the 100m backstroke eclipsed the old record of 1:06.71, a mark she set last year at the Caribbean Island Swimming Championships in Curacao, Netherlands Antilles - a Caribbean record.

The Bermudian placed 35th out of the 60 competitors and missed the mark for Olympic Games qualification by 0:00.53.

Cowen, who along with Aitken will head to the Pan-Ams next month, swam the 400m free on Sunday and his time of 4:14.39 was a new national record. It eclipsed his old mark of 4:17.23 also swum at CISC last year.

"The 400 wasn't a bad swim, I can't complain about a personal best time," he said afterwards. "I went out to feel the first 200 and was 2:01 at that mark, after that I felt like I had lead weights attached to me."

Yesterday morning he swam the 200m and again set a best time of 1:55.57. The time was inside last year's Commonwealth Games time of 1:55.88 and once again was a new national record. He placed 50th out of 94 swimmers and missed the Olympic qualifying mark by 0:00.49.

"I warmed up this morning feeling awful," he said. "I felt awful the whole race and still managed a 1.55.57.

"I know I can drop at least a second off the back half. I am not feeling real speedy and I am sore, tired, and feeling heavy but I am gonna rock at Pan-Ams for sure."