President Biden told a gathering of Democratic governors that he needs to get more sleep and work fewer hours, including curtailing events after 8 p.m., according to two people who participated in the meeting and several others briefed on his comments.

The remarks on Wednesday were a stark acknowledgment of fatigue from the 81-year-old president during a meeting intended to reassure more than two dozen of his most important supporters that he is still in command of his job and capable of mounting a robust campaign against former President Donald J. Trump.

Mr. Biden’s comments about needing more rest came shortly after The New York Times reported that current and former officials have noticed that the president’s lapses over the past few months have become more frequent and more pronounced.

But Mr. Biden told the governors, some of whom were at the White House while others participated virtually, that he was staying in the race.

He described his extensive foreign travel in the weeks before the debate, something that the White House and his allies have in recent days cited as the reason for his halting performance during the debate. Initially, Mr. Biden’s campaign blamed a cold, putting out word about midway through the debate amid a series of social media posts questioning why Mr. Biden was struggling.

Mr. Biden said that he told his staff he needed to get more sleep, multiple people familiar with what took place in the meeting said. He repeatedly referenced pushing too hard and not listening to his team about his schedule, and said he needed to work fewer hours and avoid events scheduled after 8 p.m., according to one of the people familiar with what took place at the meeting.