The hottest day in the history of the Flora London Marathon yesterday left the record field of 36,391 starters roasting in 23.5 degree temperatures. St John's Ambulance treated 5054 people, and there were 73 hospital admissions for unspecified reasons by 6.45pm last night.

But the 35,674 runners who completed the course represented a record number for the event, remarkable given that radiated heat off the road was recorded at 27.4 degrees.

Race organisers declined to comment on reports that three of those hospitalised were in critical condition. Eight have previously died in the 27-year history of the event.

Even the absent world record-holder, Paula Radcliffe, will have felt the heat, despite her long-distance observation from Boulder, Colorado, where she is training after the birth of her first child. The old elite order was incinerated in this cauldron, on a day when conditions evoked memories of the day Radcliffe sat down and wept by the roadside in Athens.

Exactly 483 days from the Olympic Games marathon in Beijing, where Radcliffe dreams of redemption, China won the London women's title for the first time. Zhou Chunxiu, who finished in 2hr 20min 38sec, said she respected Radcliffe, but warned: "I am aiming for that world record in 2008. I hope to achieve that."

Zhou broke clear with a blistering 5min 09sec mile, second quickest of the race, from the 24-mile marker. She covered the last 5000m (just over three miles) in 16.40. That would have been good enough to win the Scottish women's track title at the distance more often than not in the past decade.

By the end she had put more than a minute on Gete Wami, three times world cross-country champion, multiple world and Olympic track medallist, and winner of marathons in Berlin, Amsterdam, and San Diego. "When she applied the pace, I couldn't go," admitted the formidable Ethiopian.

The 37-year-old Romanian, Constantina Tomescu-Dita, a former Chicago winner, was third in 2:23.55, with Mara Yamaouchi the first British finisher, sixth in a very creditable 2:25.41. In these conditions it marks her as a worthy world championship contender for Osaka where August's heat and humidity will be even greater.

Yamaouchi stayed on well, closing on Lornah Kiplagat, who surrendered a long-term lead around 23 miles. But fifth was a noble finish for the Kenyan-born Dutch woman just a month after having world cross-country gold.

Zhou dented the myth of Chinese inability to travel and win. They have come to Europe with big reputations and proved fragile as chopsticks, but the 28-year-old Zhou is of sterner mettle. The only woman in the field (and one of just eight in the world) to have broken 2:20, she has won twice in Seoul, and took the Asian Games marathon title in Qatar last December by three and a half minutes. But this field was of much higher calibre.

China has confounded endurance running before. Ma Junren's army broke a slew of world records 14 years ago, fuelled by caterpillar fungus and turtles' blood, after which the spectre of doping hung heavily over his camp. But Zhou said of her win: "There's no secret. It's just up to my hard training, and the experience I have gained worldwide."

Her regime has built formidable strength and blessed her with decent 10k pace: 31.09. Most marathoners race the distance no more than twice a year. Zhou ran four in 12 months, all under 2:30, including two in 14 days in 2005. One was the Helsinki world championships, where she was fifth.

First Chinese to win a marathon major, Zhou has made meteoric progress since her first championship appearance. When 33rd in the Athens Olympics (2:42.54) she finished four places behind Britain's Tracey Morris.

Zhou collected $105,000 including time bonuses for her victory, but will not embark on a shopping spree before going home. "It's my first time in London, so I will probably buy some local specialty," she said. "Shoes or clothes? No, nothing too heavy to put in my luggage."

She will surrender some of her winnings, but was coy about how much. "I will give some to the Chinese team, for training in the future," she said. There will be no respite. Her coach at the National Sports Academy in Dalian will not permit it. "He has told me there is no time for me to go to my home. It's back to hard training. I will recover very soon, but my coach won't let me go."

Though Martin Lel, the 2005 winner, took the men's race, in 2:07.41, the biggest beneficiary of the day did not have to run a step. By derailing leading contenders for a half million dollar bonus put up by the World Marathon Majors, Lel ensured that his Kenyan countryman, Robert Cheruiyot, is invincible.

Lel is the only man who could catch Cheruiyot, winner of Boston last Monday, and of two others within the qualifying period. Lel would have to win the world title and finish no worse than third in either the ING race in New York, or Chicago this autumn, and he confirmed: "I will not do both."

The finale to the men's race was breathtaking. Eight remained in contention with less than five miles to go, and any one of five could still have won with only 300 metres remaining. Lel pulled clear with a scorching sprint up the Mall, holding off Morrocan marathon debutant Abderrahmin Goumri by just three seconds. Another Kenyan, last year's winner Felix Limo, was a further three seconds down in third.

Three of the five fastest men ever, including the world record-holder, were in the field and failed to make the podium. Paul Tergat, the world record holder, was sixth, and the iconic Haile Gebrselassie, multiple Olympic and World track champion, dropped out for the second time in three attempts here. In addition, Olympic champion Stefano Baldini, and former world record-holder and previous winner, Khalid Khanouchi, also dropped out.

n Ruaridh Campbell, last year's runner-up from Arbroath Footers, won the Lochaber marathon yesterday in 2:35.30.

McColgan keeps record
LIZ McColgan, who won here 11 years ago, was running for Leukemia Research.

In an emotional final race of her career, following 14 foot operations and the death of her father, Martin, from cancer in February, she finished in 2hr 50min 39sec.

Though she ran off the mass start, she would have placed 15th Brit in the elite race. And she preserved her record of never being beaten in a marathon by a Scot.

Though Elke Schmidt of Bellahouston Road Runners was 15th (2:47.09), she is German-born. Clubmate Helen Stuart was 29th (2:53.38), one place ahead of Glasgow University student Shona McIntosh (2:54.04). Kathy Butler dropped out at 16 miles.

"I really enjoyed it, more than any London marathon I've done," said McColgan. "But I have never drunk so much water in my life."

Dan Robinson was ninth in the men's race (2:14.14), but Britain's best result was victory in both wheelchair races. Shelley Woods, just 20, beat four-times winner Francesca Porcelato in 1:50.40, while David Weir won for the third time in 1:30.49.