It's a solution that is typical of the ever-pragmatic Angela Merkel: if you're having some difficulty standing for a period of time then simply sit down.

But as Merkel remained seated for the second time during the national anthems at an official ceremony in a rare change of protocol on Tuesday, rumours and speculation over the Chancellor's health continued to go into overdrive.

The German leader has suffered three bouts of uncontrolled shaking recently while standing at public ceremonies.

It's led the country to ask a series of questions such as: what's causing the trembling? Is Merkel really okay? Should we be worried? Is it any of our business?

READ ALSO: 'I take care of my health': Merkel sits through official ceremony after trembling spells

Though she has consulted doctors about the cause and undergone tests, Merkel herself has sought to play down the episodes, insisting that she is doing “very well” and there is no need to be alarmed about her wellbeing.

Yet the Chancellor is being watched more closely than ever, perhaps indicating a change in the mood of a country that's usually obsessed with privacy. Last week, Germany's Bild newspaper claimed that the Christian Democratic Union (CDU) was acting “as though Angela Merkel never had three trembling attacks.”

Speculation is swirling about the cause of Merkel's condition, but the widely-read daily said three clear episodes of shaking in public were “a taboo subject” within the CDU.

The conservative party did not mention them in press reviews sent each day to its leaders, even though the “mysterious trembling crises” are “the number one topic in German media,” Bild said.

However, 60 percent of Germans believe Merkel's health is a private matter, and only 34 percent said it was a matter of public interest, according to a poll published in the Augsburger Allgemeine.

Three public episodes of shaking

Merkel's health began making headlines in mid-June after she was seen shaking during a reception for Ukrainian president Volodymyr Zelensky, whom she was welcoming to her office building with military honours.

At the time it was blamed on dehydration on a hot summer's day.

READ ALSO: Merkel blames dehydration for shaking spell

Asked by a reporter about her wellbeing at a news conference about 90 minutes after the first public spell, Merkel smiled: “I've drunk at least three glasses of water and so I'm doing fine.”

But just over a week later she was seen shaking uncontrollably next to Germany's President Frank-Walter Steinmeier during a ceremony to formally appoint a new Justice Minister.

The shaking went on for about two minutes, according to a DPA photographer who was present.

Her office sought to calm nerves over the second bout of trembling in as many weeks, saying the veteran leader was en route to Osaka as planned for the G20 summit. Merkel continued her packed schedule in Japan for the summit, without even cancelling a single meeting.

However, on July 10th, Merkel began shaking involuntarily for a third time as national anthems were being played at the reception of Finnish Prime Minister Antti Rinne.

But she attended a press conference as planned just around an hour later, telling journalists that her health was no cause for concern.

“I feel very well, there is no need to worry,” she said, adding that she was simply still in a phase of “processing” a previous shaking spell, but that “there has been progress”.

“I must now keep going with that,” added Merkel, who turns 65 on Wednesday, July 17th.

Merkel being offered a glass of water at an event where she experienced uncontrollable shaking. Photo: DPA

A source close to the government had said the cause of the repeat shaking was now psychological, with memories of the first incident provoking renewed trembling at events with similar settings.

Since then, Merkel has taken a seat at official events which seems to have helped.

So the question remains: is Merkel able to carry on with her duties? The truth is that no-one knows exactly what is wrong with Merkel at the moment but the Chancellor insists she wants to get on with things.

'Camel-like'

As Chancellor, Merkel, who is frequently called the EU's most influential leader and the most powerful woman in the world, has always enjoyed relatively robust health. She has said she will leave politics at the end of her term, in 2021.

Merkel has always guarded her private life but there have been fears over her health in the past.