Radcliffe is running out of time as rival steps up

While Paula Radcliffe headed back from her Pyrenean training base yesterday, to have her state of well-being assessed in a series of scans at the British Olympic Association's Medical Institute at Northwick Park, in north-west London, today, Mizuki Noguchi was stepping up the intensity of her Olympic preparations at a high-altitude training camp in St Moritz, Switzerland.

It is not beyond the bounds of possibility that Radcliffe could yet win her battle to gain sufficient fitness to line up for the women's marathon in Beijing on 17 August, five weeks from today. The strength of her medal prospects, though, can be gauged by the ground she needs to make up on the Japanese runner who left her a broken figure on the road from Marathon to Athens four years ago.

It was in St Moritz that Noguchi built up the speed endurance that took her to Olympic marathon gold in 2004, when she pulled clear of Radcliffe before the ailing Briton ground to a tearful halt three miles from the finish.

"I am moving into high gear for the race," the 30-year-old said last week, and the gears she cranked through in the Swiss Alps before Athens included a staggering session of 45 repetition 400m runs on the training track.

Radcliffe stands unchallenged as the fastest female marathon runner of all time, with the stunning 2hr 15min 25sec she clocked in London back in 2002, but Noguchi is chasing a place in the history books as the first woman to achieve an Olympic marathon double.

That goal has been her driving force for four years now and as she moves towards it she ran a solid 1:08.25 half-marathon two months ago.

Sadly, Radcliffe has no such base from which to work on the road to Beijing. It was two months ago that a stress fracture of the femur was diagnosed. Though she has been striving to disprove the medical experts who told her that attempting to make it to the Beijing marathon was a mission impossible, she is still some way short of top gear in training. As her manager Sian Masterton said in midweek, Radcliffe is currently performing "more cross-training than usual to complement the running".

In the circumstances, it would be asking a lot even of the woman who has put the world marathon record out of sight to be in shape to mount a serious medal challenge on the streets of Beijing five weeks hence.

UK Athletics have told Hayley Haining, the nominated reserve for the women's marathon, to train as though she was preparing to run in Beijing.

In order to compete, however, Haining would need to be named as a replacement by the final selection deadline – a week today – or thereafter gain a special dispensation from the International Olympic Committee.