(Reuters) - Serena Williams may have won 13 grand slam singles titles, 12 doubles titles and two Olympic gold medals, but the American is amazed at her own success given how much she dislikes the actual athletic nature of her profession.
"I have never liked sports and could never understand how I became an athlete," the former world number one and arguably the most dominant women's player over the past 10 years told reporters after she beat Chanelle Scheepers 6-2 6-3 in the first round of the Brisbane International on Monday.
"I don't like working out and don't like anything to do with working physically. If it involves sitting down or shopping, I'm excellent at that.
"That has always been my Achilles' heel, the working out."
The 30-year-old Williams, who is well aware she is entering the twilight of her career, said while she was cutting back on her playing schedule this year, the motivation to keep playing was still there and she was not ready to retire yet.
"I think for me it's all about motivation as opposed to my skill or anything else," she said. "As long as the motivation's there it's definitely going to be cool.
"I'm not playing a full schedule this year. I just want to be able to do other things that I'm doing and I think that will help keep my motivation up.
"I'm always preparing myself for life after tennis (but)... I don't want to go anywhere anytime soon."
Williams entered the Brisbane tournament because she had never been there before and felt a new city would keep her fresh as she sought to win the Australian Open's Daphne Akhurst Memorial Cup for the sixth time.
South Africa's Scheepers gave her a tougher than expected workout, though Williams had not played since a sensational outburst against the chair umpire in the U.S. Open final last September.
Williams was censured and fined $2,000 for her outburst in the final, which she lost to Australia's Sam Stosur, said prior to the Brisbane tournament she would not dial down her intensity.
That intensity was needed at certain crucial points on Monday as the fourth seed overpowered a determined Scheepers to set up a second round clash with Serbia's Bojana Jovanovski.
"I think I did good (and) have shaken a bit of the rust off but I played a really good player, it wasn't an easy first round at all," Williams said. "I definitely have tons of room for improvement."
Former French Open champion Ana Ivanovic set up a second-round clash with Australian Open champion Kim Clijsters after she easily accounted for Austria's Tamira Paszek 6-3 6-3 in just under 80 minutes.
"There were some nerves involved, particularly early on but I felt I played well," Ivanovic said.
"Obviously there is still some room for improvement but it was the first match and I'm happy."
Ivanovic has played Clijsters four times, losing all four matches, but the Belgian is coming back from an abdominal injury and has only played once, her first round victory over Romania's Simona Halep on Sunday, since last August.
"It's a tough match, no doubt, at least it's in the second round and not the first round," Ivanovic said.
"I just need to go out there and test myself and push and see how far (away) I am from the top players.
"It will be a battle and I just want to try and apply things that I have worked on and see how that plays."
Top seed Stosur easily accounted for Anastasiya Yakimova of Belarus 6-2 6-3, while men's second seed Gilles Simon thumped Ryan Sweeting 6-3 6-4.
(Reporting by Greg Stutchbury in Wellington; Editing by John O'Brien)