On the first day of a long Christmas stay at Camp David, Bush was up at 6:15 a.m. and jogging two hours later. He ran three miles in 21 minutes, 15 seconds. Later, he went to church.
Mr. Bush is feeling "absolutely, positively fine," said White House spokesman Adam Levine.
Experts estimate that 15 out of every 1 million people vaccinated for the first time will face life-threatening complications, and one or two will die. Reactions are less common for those being revaccinated, as Mr. Bush was on Saturday.
On Dec. 13, Mr. Bush directed as many as 500,000 U.S. troops to get smallpox vaccinations, part of an effort to guard against bioterrorism. He promised at the time to get the shot himself, though he said his family would not, because the risk of a domestic attack did not justify it.
Also at Camp David were Mr. Bush's parents, his twin daughters, and Laura Bush and her mother, Jenna Welch.
He and his father went for a walk Saturday night, and the family watched the film "About Schmidt," starring Jack Nicholson.