Libby Lenton won the women's 50 metres freestyle final on Sunday to capture a record-equalling fifth gold medal at the world championships.

The 22-year-old Australian powered to victory in 24.53 seconds, successfully defending the title she won in Montreal two years ago.

Therese Alshammar of Sweden was second in 24.62 after winning the 50 butterfly and Marleen Veldhuis of the Netherlands was third in 24.70 but it was Lenton who once again got her hand on the wall first.

Lenton joined American Tracey Caulkins (1978) as the only women to win five gold medals in a single world championship after winning the 100 freestyle, 100 butterfly and two relays.

"If someone had told me I would have won five gold medals I would have pretty much have laughed in their face," said Lenton, who is getting married next week.

"I love racing - that's why I do the training. I love to get in there and have a go at a lot of events.

"I've had harder meets and tougher programs. For me, this meet was pretty much perfect.

Lenton's performances in Melbourne ended years of frustration for the Queenslander and provided the perfect platform for next year's Beijing Olympics.

Lenton won two relay golds at the 2004 Athens games but failed to win either of her individual events.

She finished second to Inge de Bruijn in the 50 sprint and failed to make the 100 final despite going into the event as the world record holder.

Lenton could have won seven golds in Melbourne and although she came up two short, she said she was brimming with confidence about her prospects in Beijing.

"Maturity and experience as an athlete. I've had many ups and downs, many experiences and all that hard work and grind," she said.

"I wasn't expecting to win one, let alone five. I just wanted to go out there and have fun.

"You don't come into a meet expecting anything new, you come in with hopes and dreams and goals, but not hope for medals.

"I think sometimes you learn more from disappointing swims than successful ones."