For 25 hours straight, Cory Booker stood on the Senate floor delivering the longest speech in the chamber’s history without stopping to eat, go to the bathroom or even sit down.

“My body is definitely going through it right now,” Mr. Booker said in an interview Wednesday evening. “But my spirit is so high.”

The senator, who started speaking Monday evening to condemn the Trump administration and continued to talk until Tuesday night, said that before he started talking, he had not drunk water since Sunday night, so that he would not have to stop and use the bathroom. He also said that he fasted for days leading up to the speech.

Mr. Booker said that his Oura ring repeatedly asked if he was working out during the speech. At one point, about seven hours in, it showed that his heart rate shot up to over 100 beats per minute, where it stayed for some time. When he finally went to bed — after talking to reporters, eating a banana in a Senate cloakroom and drinking plenty of water — he slept for around six and a half hours.

Being able to deliver such a lengthy speech, without any sort of break, is “an amazing physical feat, absolutely,” said Dr. Santina Wheat, a family medicine doctor at Northwestern Medicine Delnor Hospital in Illinois.

It also goes against all the advice she gives her patients about staying hydrated, getting plenty of rest — and, yes, using the bathroom when they need it.

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