Back to business for muscle-bound Bolt

After a day spent in the full glare of the media spotlight, Usain Bolt returned to what he does best on Friday morning, training with his Jamaican teammates at London's Olympic Park.

To the accompaniment of a blast of music drifting across the road from the Olympic Stadium, where Bolt will carry the Jamaican flag at the opening ceremony later on Friday, the most recognisable track and field athlete in the world went about his sprinting drills with training partner Yohan Blake.

While on Thursday he faced a forensic grilling from the world's media at a 50-minute news conference followed by a string of interviews stretching into the evening, his exertions on a warm, overcast morning were largely ignored by the many other athletes, all intent on their own final preparations for the Games.

An imposing figure even among so many finely-honed bodies, Bolt thundered down the track from a standing start, his gold chain bouncing on his chest as he built up to something approaching full speed.

At the end of every run, Bolt planted both hands in the small of his back, the source of the stiffness that has caused him hamstring problems and provoked concerns that he might not be fit to defend his 100m and 200m titles.

Regardless of the truth behind the debate over whether he is 95 or 100 percent fit, there was none of the fractious tension that can surround elite athletes when they are not feeling at their best ahead of a big competition.

Bolt greeted friends among the many other Caribbean athletes training on the track with handshakes and hand slaps and roared with fake outrage when Blake interrupted one of charges by sliding a nearby hurdle into his path.

There was a time when that might have been Blake's best chance of beating his compatriot but the 22-year-old is now world champion, bettered Bolt in the 100m and 200m at the Jamaican trials and owns the best 100m time of the year (9.75 seconds).

Jamaica's sprinters had a sensational Beijing Games and with talents like Blake having emerged since, confidence is high they can maintain that level in London.

"People are expecting us to do well so they are preparing for us, but I think we should do as well as Beijing or perhaps a little bit better," coach Maurice Wilson told Reuters, before suggesting there might be a talent or two beyond the household names who could spring a surprise.

Until the athletics at the Games starts on Aug. 3, however, Bolt remains the biggest name, Jamaican or otherwise, in the firmament of track and field.

His fifth run down the track stuttered to a halt 10 metres earlier than the others and that was the end of his session.

One European athlete, looking for an official so he could return a tape measure he had borrowed and get his accreditation back, watched the muscle-bound figure sauntering back up the track towards his team mates.

"He's too big and heavy, that's why he can't win this year," he said with a shrug to the solitary member of the media watching on.