Possible Clues:

• Winter Olympics event since 1964
• Olympic sport since 1964
• Downhill racer similar to a sled
• Bobsled cousin
• Scoot down a chute
• Olympics item ... or the winning word in the 1984 National Spelling Bee
• Sled at the Winter Olympics
• Feet-first Olympic event
• Sport timed to the thousandth of a second
• Thrust stomach out in Olympic event