Chicago Marathon

Marathon's under way -- and it promises to be a warm one

9:06 A.M. -- In the 20th mile of the men's race, Tsegaye Kebede surged with a 4:40 mile. The leaders were down to 3: Samuel Wanjiru, Feyisa Lilesa, and Kebede.

8:44 A.M. -- Legendary Swiss wheelchair racer Heinz Frei turned his Chicago Marathon debut into victory.

In the women's race, Astede Baysa took the lead by herself in the 16th mile. She won this year's Paris Marathon in 2:22:04. Although only 23 years old, this is her 14th marathon. Reigning Boston Marathon champion Robert Kiprono Cheruiyot fell off the lead pace in the 19th mile of the men's race.

8:40 A.M. -- In the women's race, Mamitu Daska and Astede Baysa moved away from Askale Magarsa as they reached the halfway point in 1:09:45.

8:26 A.M. -- The men went through the halfway point in 1:02:35, with all the top pack of eight including all the contenders. In the women's race, Askale Magarsa, Astede Baysa and Mamitu Daska of Ethiopia were running together at the lead through the first 10 miles, with defending champion Liliya Shobukhova of Russia hanging about 10 meters back.

7:56 A.M. -- Despite the heat, the elite men's pace began to accelerate dramatically in the 5th mile, which they covered in 4 minutes, 40 seconds, and the 6th, in 4:39. It was projecting to a 2 hour, 4 minute, 27 second finish, which would match the 3rd fastest marathon ever.

The expected contenders, including defending champion Sammy Wanjiru of Kenya and four Ethiopians, all were in the nine men running at the lead after 6 miles.

The women's race shook out earlier, with a group of four moving into the lead.

With little cloud cover and little shade, the fast early pace was unlikely to continue.

7:36 A.M. -- Temperatures hovered in the low 60s as the 1st runners spilled out onto Columbus Drive at the north end of Grant Park at the start of the 2010 Bank of America Chicago Marathon.

For the 3rd time in 4 years, the race began in unseasonably warm temperatures.

The forecast for today is for temperatures to peak in the mid-80s, the warmest weather for the marathon since 2007, when temperatures reached nearly 90 degrees with high humidity and the course was closed after 3½ hours to those who hadn't reached the halfway point. Another significant difference between Sunday's race and the heat disaster of 2007 was humidity and dew point. The humidity was considerably higher in 2007, when some 300-plus runners were treated for heat problems.

Runner Chad Schieber, a 55-year-old police officer from Midland, Mich., died that year after collapsing on the race route and 317 other participants were hospitalized for heat- and dehydration-related illness.

The course this year features 6 more aid stations than in 2007, and race planners have adopted a colored warning system for runners.

The 2010 marathon promises to be the most competitive in the 33-year history of the event, with 3 of the top runners in the World Marathon Majors standings competing in the men's field. Defending champion Sammy Wanjiru of Kenya and 2010 Virgin London Marathon champion Tsegaye Kebede of Ethiopia are tied in the marathon series point standings, and a victory by either could seal the WMM title and a $1 million season prize.

Also in the field is Robert Kiprono Cheruiyot of Kenya, who's competing in his 1st marathon since breaking the course record at the Boston Marathon by 82 seconds this spring. Defending women's champion Liliya Shobukhova of Russia, who won the Virgin London Marathon in April with a time of 2:22, leads a strong women's field that includes 2009 runner up Irina Mikitenko of Germany.

But the overwhelming majority of the 45,000 runners registered for the race will be happy to navigate the winding 26.2-mile course in double or triple the time of the leaders. Only 12,000 runners qualify to run in the seeded "corrals" of experienced runners who can prove they have finished a marathon in four hours or less.

"I am hoping to finish before they turn the timer off, maybe 6 hours," said Matt Covington of San Luis Obispo, Calif.

At 295 pounds, Covington is some 30 pounds lighter than when he started training three months ago, after a co-worker convinced him to run to raise money for autism research. "People keep telling me you get a second wind and feel great, but I have hated every minute of it. But I signed up and I do not want to let anbody down."

For Chicagoan Sue McGrath, there was no better day to run her 1st marathon.

"It is 10-10-10, what better day to do it than today," said McGrath as she walked to the starting corrals around 7 a.m.