Hillary Clinton has made her first public appearance since taking three days off the campaign trail after being diagnosed with pneumonia.
The Democratic presidential nominee smiled and waved as she climbed the steps of her campaign plane in White Plains, New York.
She told reporters she is “doing great” before flying off to a rally in Greensboro, North Carolina.
Her return comes a day after her doctor said she was “healthy and fit”.
The physician’s note also said 68-year-old Mrs Clinton’s cholesterol level and heart rate were all within normal ranges.
On Thursday, Donald Trump released a letter from his doctor saying he is in “excellent physical health”.
The Republican nominee earlier this year released a brief memo from the same physician asserting he would be “the healthiest individual ever elected to the presidency”.
The 70-year-old businessman also discussed his health with Dr Mehmet Oz during a taped episode of the medical chat show, which aired on Thursday.
At a rally in Ohio on Wednesday, Mr Trump used Mrs Clinton’s recent health scare to cast doubt on her stamina.
He said: “I don’t know folks, do you think Hillary Clinton would be able to stand up here for an hour?”
On Sunday, she had to be helped into a van after abruptly leaving the World Trade Center memorial after aides said she felt “overheated”.
The Clinton campaign cancelled the remainder of the former secretary of state’s public events before revealing her diagnosis.
The polls indicate a tight race nationally and in the key battleground states, with 54 days to election day.