BEIJING, China (AP) — He set world records, won Olympic gold medals, danced on the track and made the sprint game feel fun again.

One thing Usain Bolt cannot do, he insists, is serve as the lone savior for track and field.

“I can’t do it by myself,” Bolt said Thursday.

Back in Beijing, where he set three world records and won three gold medals at the 2008 Olympics, The World’s Fastest Man is preparing for the world championships this time around.

But his news conference Thursday was less about reminiscing and more about the topic that has swallowed up his sport of late: Doping.

“People say I need to win for the sport,” he said. “But there are a lot of other athletes who are running clean, and they’ve been running clean their whole career. It’s not just on me but on all the athletes.”

A report this summer from German broadcaster ARD and The Sunday Times in Britain found that 146 Olympic and world championship medals in middle- and long-distance races were won by athletes who have recorded suspicious tests. The International Association of Athletics Federations has strongly denounced the report while defending its anti-doping practices.

Even while his own country, Jamaica, has come under scrutiny for its less-than-robust anti-doping program, Bolt has remained unscathed. But when he lines up in the final Sunday (assuming he makes it), his main competition figures to come from American sprinters Justin Gatlin and Tyson Gay and Jamaican teammate Asafa Powell, all of whom have served doping suspensions over their careers.

One reporter equated the race to a showdown between good (Bolt) and evil (Gatlin). Neither runner bought into that.

“I’m not trying to win any popularity contests or win anybody over,” Gatlin said in an interview with The Associated Press, shortly after Bolt’s news conference ended. “I’m trying to do what I’m supposed to do. Hopefully my actions on the track will show that to the people who really care. That’s all that really matters.”

Gatlin, who has this year’s best time at 9.74 seconds, can race because rules specifically ensure that an athlete who has doped can return to the sport if he’s served out his suspension. Some find this unfair. Bolt doesn’t want to wade into that debate, either.

“Rules are rules and are there for a reason,” Bolt said. “If the rules say you can get back in the sport, I can’t do anything about it. I abide by the rules and that’s pretty much all.”

Bolt, who turns 29 on Friday, pointed at his left hip and described what’s been holding him back this year as a joint problem that prevents him from getting to full power on his stride. He’s raced in only one meet all season, where he ran a 9.87 in the 100, but said recent training sessions have been going well.

“It’s frustrating when you can’t go out and prove yourself,” he said.

But his coach, Glen Mills, has been smiling and giving Bolt the thumbs-up after recent practice sessions.

“For me, I’m not worried about anything,” Bolt said. “As long as my coach is happy.”

Along with his health, some time at the news conference was spent getting caught up on the really important stuff:

—His goatee will stay for the worlds. He’s superstitious and wants to stick with that look for now, and a clean shave when the Olympics come.

—At the Beijing Olympics, Bolt dined almost exclusively on Chicken McNuggets. He said there’s better food available this time — and, at 29, he needs to be more careful about what he eats, anyway — so that won’t be his diet.

—In 2008, his birthday fell during the Olympics, and fans at the Bird’s Nest serenaded him with “Happy Birthday” — one of the many memorable moments he enjoyed that year. This time, though, it falls on the day before the start of competition. “Zero plans for tomorrow,” he said. “I’m sure someone will get me a cake.”

Then, the subject turned back to performance enhancers.

“All I’ve been hearing about the past couple weeks is doping, doping, doping,” Bolt said. “It definitely is sad that it’s in the forefront of the world championships, and it’s not about the competition that’s coming up. For me, it’s sad but I can’t do anything about it because you’re the ones writing about it.”