Crown Princess Mary shows her sporty side as she takes on challenge with children

Crown Princess Mary showed off her sporty side as she joined her husband Crown Prince Frederik's annual challenge on Monday.

The mother-of-four, 51, took part in the Royal Run, which saw events in five different cities.

The crown princess donned a branded T-shirt, with leggings and trainers, as she ran the mile-long race in Nyborg. Mary also later walked the 5km event in Nykøbing Falster.

The Royal Run was initiated by Crown Prince Frederik to mark his 50^th birthday in 2018, and has since become an annual race. This year's event comes just days after the future king celebrated his 55^th birthday on 26 May.

Frederik participated in the mile-long race in Aabenraa, as well as 5km run in Herning and a 10km race in Copenhagen and Frederiksberg.

Meanwhile, Crown Prince Frederik and Crown Princess Mary's four children all ran a mile during the family race in Copenhagen.

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Prince Christian, 17, Princess Isabella, 16, and 12-year-old twins Prince Vincent and Princess Josephine, posed for a group photo before heading off to the start.

The young Danish royals all wore branded Royal Run tops, with Christian and Vincent opting for neon pink trainers.

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© Getty

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 Around 93,624 runners registered for the Royal Run across the five cities.

Crown Prince Frederik and Crown Princess Mary are avid sports fans, having met at the 2000 Summer Olympics in Sydney.

But Australian-born Mary was not aware that the man she was speaking to was in fact royalty when they first met!

"The first time we met we shook hands. I didn't know he was the prince of Denmark. Half an hour later someone came up to me and said, 'Do you know who these people are'?" Mary revealed in a 2005 interview about meeting the heir to the Danish throne.

The couple celebrated their 19^th wedding anniversary earlier this month.

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Frederik has completed marathons in Copenhagen, New York and Paris, and is a big tennis fan, having attended Wimbledon several times.

It's been a busy few weeks for the Danish royal couple, after attending King Charles and Queen Camilla's coronation at Westminster Abbey in London.

Crown Prince Frederik and Crown Princess Mary were among the 2,300-strong congregation at the church, with Mary looking elegant in a mauve ensemble for the historic occasion.

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The couple and their four children also attended Count Henrik's confirmation in Paris on 18 May.

The 14-year-old is the son of Prince Joachim and Princess Marie, who also share a daughter, Countess Athena, 11.

Joachim, Marie, Henrik and Athena are set for a big move to Washington DC in the US this summer. The prince will take up a new role under the Ministry of Defense as defense industry attaché at the Danish Embassy in Washington DC.

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