President Trump underwent a two-hour doctor’s examination on Saturday at Walter Reed National Military Medical Center, which the White House said was part of a routine annual physical and included lab work.

The appointment was not on the president’s schedule, in contrast to a previous physical that Mr. Trump had in February, also at Walter Reed outside Washington.

In a statement, Stephanie Grisham, the White House press secretary, said Mr. Trump, 73, was taking advantage of a free weekend to begin portions of his annual physical, and was anticipating a busy schedule in 2020. She did not specify what types of tests Mr. Trump had.

“The president remains healthy and energetic without complaints, as demonstrated by his repeated vigorous rally performances in front of thousands of Americans several times a week,” Ms. Grisham said.