OSAKA, Japan, Aug 30, 2007 (AFP) - The ravages of time inevitably catch up with the world's top athletes - but some escape the ticking clock much longer than others.

The current world championships in Osaka are a case in point.

Jamaican-born Merele Ottey, now representing Slovenia and still in eye-popping shape, became the oldest women's competitor ever at a world championships when she ran the 200m heats here aged 47.

Only Isareli Ayele Setegne can lay claim to be being older. He competed in the marathon at Helsinki two years ago when he was 50.

Considering she made her worlds debut in 1983, when Ronald Reagan was president of the United States, her performance was highly creditable.

"I beat a few of them out there, so I'm not complaining," she said after timing 11.54 seconds.

"Obviously I enjoy it, otherwise I wouldn't be here. Running races is what I do," added a woman who holds a record 14 world championship medals.

But Ottey isn't the only golden oldie still making waves on the world stage.

Germany's Franka Dietzsch defied the age barrier to win her third discus throw crown on Wednesday.

At 39, Dietzsch became the second oldest gold medal winner in any event in world championships history.

Only fellow discus thrower Ellina Zvereva of Belarus was older, when she won the title aged 40 in 2001.

"This is crazy. This is my third world title - I had some tears of joy in my eyes after the competition," she said, adding that she planned to continue until the Beijing Olympics if her heatlh held up.

"It is very surprising for me as I beat all the young girls."

A 41-year-old, Iryna Yatchenko, was competing in the same event and finished tenth.

Athletes in field events tend to last longer than on the track.

Ottey is the most glaring exception, winning a 200m world title when 35 in 1995. Few come close to the super-human sprint queen, although Germany's Franka Dietzsch and France's Patricia Girard were also 35 when they won relay golds.

Another elder stateswoman still putting her best foot forward is Mozambique's Maria Mutola.

The 34-year-old former world champion, considered one of the greatest 800m racers ever, stands out because she is still highly competitive.

She made her worlds debut 16 years ago and should have had a medal here if not for a leg injury shattering her dreams as she rounded the last bend in third place during the final this week.

Mutola, who is also the youngest 800m gold medallist ever, staggered off the track to lie on her back. It is unclear whether she will be back.

"I already have three world outdoor titles, but I'm still looking for another one if I can," she said ultra-competitive Mutola before the race.

At the other end of the age scale, several runners at the Osaka championships can claim to being the youngest world champions.

Ethiopia's Tirunesh Dibaba won the 5,000m aged just 17 in 2003. She was unable to defend her title here due to stomach cramps.

She also holds the 10,000m age record, winning that race aged 19 in 2005, and remains the youngest champion in any track or field event ever.

American Sanya Richards, also competing in Osaka, was a 4x400m champion when just 18 while her teammate Allyson Felix claimed gold in the 200m in Helsinki two years ago when she was 19.