Photo: The Canadian Press

Democratic presidential candidate Sen. Bernie Sanders speaks we reporters outside his home, Tuesday.

Bernie Sanders began reintroducing himself to the 2020 campaign on Tuesday, venturing outside his Vermont home to say that he doesn't plan on leaving the presidential race following last week's heart attack – but that he may slow down a frenetic pace that might have contributed to his health problems.

"We were doing, in some cases, five or six meetings a day, three or four rallies and town meetings and meeting with groups of people. I don't think I'm going to do that," Sanders told reporters when asked what his schedule may look like going forward. "But I certainly intend to be actively campaigning. I think we're going to change the nature of the campaign a bit. I'll make sure that I have the strength to do what I have to do."

Pressed on what that meant, Sanders replied: "Well, probably not doing four rallies a day."

Sanders' campaign has said he will be at next week's Democratic presidential debate in Ohio. But it hasn't commented on if or when he'll resume campaigning before that – or what his next steps will be. NBC News announced it would air an "exclusive" interview with Sanders, his first since the heart attack, on Wednesday.

His health problems come at a precarious time, since Sanders was already facing questions about being the oldest candidate seeking the White House, and he has seen his recent poll numbers decline compared to 2020 rival Elizabeth Warren, his chief competitor for the Democratic Party's most-progressive wing.

Sanders, a Vermont senator, also recently shook up his campaign staff in Iowa and New Hampshire, which kick off the presidential nominating process.

"I must confess, I was dumb," Sanders said in front of his house, speaking in soft, calm tones with his wife, Jane O'Meara Sanders, looking on behind him. "Thank God, I have a lot of energy, and during this campaign I've been doing, in some cases, three or four rallies a day all over the state, Iowa, New Hampshire, wherever. And yet I, in the last month or two, just was more fatigued than I usually have been. And I should have listened to those symptoms."

Supporters privately conceded that the timing of the heart attack – which came just as the impeachment inquiry against President Donald Trump was escalating – helped limit the political fallout. But they also acknowledge that he will have to more directly address lingering health concerns then, if not before.

And they hinted changes would be coming to better keep their candidate healthy.

"We're going to look at everything – the whole campaign in its totality – and make adjustments where necessary," said national campaign co-chair Nina Turner, who spoke with Sanders at length on Tuesday during a call with his four national co-chairs. "But make no mistake: Sen. Bernie Sanders is as committed, more so, even more now than he always has been, if that's even possible."