U.S. President Donald Trump on Sunday defended what he described as his exercise regimen, tweeting a justification for his frequent golf outings and claiming them as sufficient physical activity.

"My 'exercise' is playing, almost never during the week, a quick round of golf. Obama played more and much longer rounds, no problem," Trump tweeted.

CNN has previously fact-checked Trump's claim that he has played less golf than his predecessor; Trump has played more than twice as many rounds of golf than former president Barack Obama had at the same point in his presidency. Trump paid his 276th visit to one of his golf properties on Saturday.

Trump also defended his frequent golf-playing by arguing he often gets work done on the links.

"I play VERY fast, get a lot of work done on the golf course, and also get a 'tiny' bit of exercise. Not bad!" he tweeted.

Before winning the presidency, Trump was a frequent critic of Obama for playing golf in office. But Trump has spent many weekends at his various golf properties in Florida, New Jersey and Virginia, sometimes bringing lawmakers or business leaders with him.

Trump has long reacted strongly to scrutiny of his physical or mental health, last week claiming to have "aced" a cognitive test without providing proof.

It was the president's latest attempt to dismiss questions about his mental capabilities and attempt to call into question those of presumptive Democratic presidential nominee Joe Biden.

The White House would not provide details of the test or say whether he was referring to a more recent evaluation than the one he underwent in 2018.

Trump's general medical status has frequently been the source of speculation.

In June, the White House provided a positive look at an annual physical, saying the president's cholesterol was down from previous years, but it has never provided a complete explanation for an abrupt November 2019 trip to Walter Reed National Military Medical Center that the White House claimed was meant to get an early start on his yearly physical.

At the time, the White House said it was a "routine checkup," though it was unannounced and wasn't on the President's internal schedule the morning he went there.

New questions about the president's health surfaced last month when he appeared unsteady while descending a ramp at West Point's commencement ceremony. Trump later raised the episode repeatedly, insisting his leather shoes made walking down the ramp difficult.