LITTLE ROCK - A 27-year-old Wisconsin man collapsed and died Sunday after completing the 26.2-mile Little Rock Marathon. Adam Nickel, who was attending graduate school at the University of Wisconsin in Madison, collapsed at 11:03 a.m. CST, shortly after he crossed the finish line of the race. Emergency personnel used mouth-to-mouth resuscitation to try to revive Nickel until an ambulance arrived with a defibrillator. He could not be revived and was pronounced dead after being taken to the University of Arkansas for Medical Sciences Hospital. The marathon's medical director, Dr. Kent Davidson, said at a news conference Sunday that no determination had been made yet on what caused Nickel's death. "He died at UAMS in the emergency department," Davidson said. "We never (detected) a heart rhythm the whole time we tried to resuscitate him." An autopsy was scheduled for Monday, Pulaski County Coroner Mark Malcolm said. Preliminary results could be released after the procedure, he said. Temperatures Sunday morning during the race ranged from the high 50s during the early miles up to the mid-60s by late morning, according to the National Weather Service. The race attracted about 9,000 entrants, race officials said in a news release. "The members of the Little Rock Marathon Committee would like to offer our condolences and prayers to (Nickel's) family and friends," race director Gina Marchese-Pharis said. Nickel was running his sixth marathon; his official Little Rock time of 3:02:26 is considered an elite time. He was preparing for a spring event in San Diego as part of the Leukemia & Lymphoma Society's Team In Training, as a tribute to his grandmother, according to the Post Crescent newspaper in Appleton, Wis. Nickel, from Kaukauna, Wis., was studying pharmacy at Madison. He also was a high school and college wrestler. "He crossed the finish line, smiled and dropped," said Shirley Thiel of Black Creek, Wis., a friend of his who accompanied him from Madison to Little Rock. "There was no indication that anything like this would ever happen." She said she knew of no health problems he had. "Everybody who knew him loved him," she said, describing him as "quiet, with a great sense of humor." Sunday's race was the sixth running of the Little Rock Marathon. Nickel's death was the first in the history of the event. (Copyright 2008 by The Associated Press. All Rights Reserved.)