06/07/2014 at 05:35 PM EDT
Is she spiking her afternoon tea with Red Bull? It might be the only way to explain how Queen Elizabeth II
is able to keep up with a hectic schedule that would tire out people half her age.
The smiling 88-year-old attended the Epsom Derby horse race on Saturday after her busiest week in years.
The Queen had jetted back to England from France, where she had been on a three-day state visit, attending the D-Day commemorations
But before leaving France on Saturday morning, she toured a flower market in Paris that was named in her honor
The monarch spent the previous day paying tribute to veterans of World War II at the 70th anniversary of the Allied invasion – and had spent much of it on her feet. That night she and husband Prince Philip, 92, attended a state banquet at Élysée Palace as the guests of French President Hollande.
The Queen's busy schedule seems to be putting to rest claims made earlier this year
that her son and heir, Prince Charles, was set to step in and take over more and more duties for her.
While that has happened to a degree, her work rate has kept apace since she started her official public duties in February. "There is a very full year ahead," one senior Palace source told PEOPLE at the time. And these last several days have been particularly busy.
On Tuesday the great-grandmother hosted a garden party for around 8,000 members of the public. Supported by her husband, as well as Prince Charles, 65, and other members of the royal family, she chatted with many of the guests, who'd been invited to the party in honor of their contribution to public life, service and charities.
Wearing the same primrose Angela Kelly-designed outfit that she wore to grandson Prince William
's wedding in 2011, the Queen held her see-through Fulton umbrella and stoically carried on shaking hands through a torrential downpour at one point.
Guest Jenny Morton, 59, a teacher from St. Martin's in the Isles of Scilly, said, "This is the first time we've been to London in 40 years. We told the Queen this and she said, 'You haven't chosen a very nice day.' "
On Wednesday, she took center stage for the state opening of Parliament. Riding in her new carriage and dressed in her crown and heavy 18-foot red velvet Robe of State, she read out the government's plans for laws in the coming year.
Then came the trip to France. But while she was very much in the public eye over the past few days, the Queen was also busy with matters that took place away from the cameras. "The role of the Queen isn't just what you see," a senior royal source tells PEOPLE. "There is so much else going on behind the scenes and she's very much engaged in those areas."