By Alexander Smith and Peter Smith

WEYMOUTH, England (Reuters) - Britain's Ben Ainslie became the most successful Olympic sailor on Sunday, winning gold in the single-handed Finn class to claim a record-breaking fifth consecutive medal.

He then indicated he would not try for a sixth.

"You can never say never, but I don't think I can sail one of these again. It's killing my body so I don't think you will see me in Rio (for the 2016 Games)," he told the BBC.

"But it's the best way to bow out at a home Olympics."

Sailing in perfect, sunny conditions on home waters off the south coast of England, Ainslie added to his three golds and a silver in successive Games by beating Danish sailor Jonas Hogh-Christensen on points.

Unfancied at the start of the Olympics, the Dane struggled to find the winning form he has shown all week and failed in his mission to defend the record of four golds held since 1960 by his countryman Paul Elvstrom.

Arms aloft, with a flare billowing red smoke in each hand, Ainslie celebrated a narrow victory in front of a huge cheering home crowd packed onto the grassy slopes of the Nothe fort immediately above the race course.

"It's been the hardest couple weeks of my life," the 35-year-old said of sailing the physically demanding Finn dinghy which has caused him back and knee troubles.

His boat, known as "Rita", was the same one he sailed to victory in the two previous Olympics.

Pieter-Jan Postma of the Netherlands was beaten to the bronze overall by Sunday's medal race winner Jonathan Lobert of France.

The Briton and the Dane were ninth and 10th respectively in the race, giving them enough points to claim their medals, with Postma finishing fourth overall in the heavyweight Finn class.

(Reporting by Alexander Smith; Editing by Mark Meadows and Jason Neely)