Speed-skating fans shouldn't expect to see new world records at the Winter Games in Russia despite advances in technology and training, a U.S. scientist says. And it's all down to altitude, Robert Chapman at Indiana University says; in Sochi, skaters will face off at sea level, where air resistance is enough to slow times compared to races held at higher altitudes. "All the world records in speed-skating were set at Olympics or events that were held at altitude, like Salt Lake City or Calgary, where there is less air resistance slowing the skaters down," Chapman said. "Usually, we think that altitude makes you slower, and that is true for distance running, but not for 'high velocity' events like speed-skating," said Chapman, whose research at the university's School of Public Health-Bloomington includes performance issues at altitude. "At lower altitudes, air resistance is a greater factor than the lower oxygen delivery to the muscles [at higher altitudes]." The air resistance also affects athletes in skill sports, he said, requiring competitors in sports such as figuring skating, ski jumping and snowboarding to retool highly technical moves to accommodate more or less for air resistance. "After thousands upon thousands of moves, certain motor patterns become ingrained for athletes," Chapman said. A different altitude will change the feedback they get from balance and body sense, he said. "It's something that needs to be incorporated into their practices," he said.