WASHINGTON -- U.S. Sen. Johnny Isakson plans to re-emerge in public on Friday after cracking three ribs.

News broke of Isakson's injury over the weekend amid talk that he had canceled an appearance at a University of Georgia political science class scheduled for this Friday. But a news release this morning announced that Isakson will speak to Charles Bullock's class as planned, then hold a press conference afterward -- to show the world he's undeterred by the injury.

Just how Isakson was injured isn't clear. This morning, the Marietta Daily Journal quotes an Isakson spokeswoman as saying the senator was hurt while moving furniture.

Isakson also will give a public lecture on international trade and economic growth Friday afternoon in Athens.

The 70-year-old senator is seeking a third term next year. So far his only announced opposition is DeKalb County minister and MARTA engineer Derrick Grayson, a Republican.

Update 3:30 p.m. Isakson spokeswoman Amanda Maddox said Tuesday that Isakson did not suffer the injury in a fall and has always wanted to keep his trip to Athens as planned. This story has been updated accordingly.