Dennis Klaaijsen: the windsurfing marathonist

Dennis Klaaijsen has improved his world record for the longest non-stop 24-hour windsurfing marathon.

The Dutch windsurfer sailed 728 kilometers (393 nautical miles) around Rotterdam, in the Netherlands. Klaaijsen decided to start the challenge in the Grevelingen lake, just like he did last year.

Twelve months ago, Dennis Klaaijsen was able to sail 613.8 kilometers (331.4 nautical miles) to set a new Guinness World Record. This time he improved his own mark by more than 115 kilometers (62 nautical miles).

"Last year I made 630 kilometers in 24 hours, but I knew someone could do it. My closest competitor is an Australian with 550 kilometers. It is still a big difference," says Klaaijsen.

The 39-year-old windsurfer will now take a break from Guinness World Record attempts. "I am not planning to give it another try. Now the ball is in other's court."

Take a look at the best Guinness World Records in windsurfing.