On August 14, 2008, at 0910 eastern daylight time, a Cessna 172R, N21SZ, collided with runway 21R (3,802 feet long by 100 feet wide, asphalt) following a loss of control while landing at the Cincinnati Municipal-Lunken Airport (LUK), Cincinnati, Ohio. The student pilot was not injured. The airplane received substantial damage to the firewall. The solo training flight was operating under Title 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed and no flight plan was filed. The flight originated from the Blue Ash Airport (ISZ), Cincinnati, Ohio, at 0830. The pilot reported the purpose of the flight was to practice landings at a tower controlled airport. He stated he landed too fast and the airplane bounced on touchdown. He attempted to recover the landing, but the airplane began to porpoise. The pilot reported the airplane porpoised several times prior to the nose gear collapsing and the airplane coming to rest on the runway.