Time to open the bubbly! Pippa Middleton delays celebrations to complete 50-mile race a day after turning 32... but at least she has brother James and her ex for company 

  • Pippa completed the 50-mile race a day after her 32nd birthday
  • The race is reported to be one of the most gruelling 'swimrun' events in the world
  • It spans 26 of the Stockholm archipelago's 1000 islands
  • Competing alongside Pippa was her brother James, her ex James Matthews and friend Jöns Bartholdson

Pippa Middleton has completed one of the most gruelling endurance races in the world just a day after her birthday.

The Duchess of Cambridge's younger sister, who turned 32 on Sunday, took part in the 50-mile ÖTILLÖ swimming and running event in Stockholm, Sweden - a challenging 50-mile route across 26 of the archipelago's 1000 islands.

Although super fit Miss Middleton delayed birthday celebrations with her boyfriend and family, she was joined by brother James Middleton, old friend Jöns Bartholdson and ex-boyfriend James Matthews - who were her teammates for the race on Monday.

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The Duchess of Cambridge's younger sister, who turned 32 on Sunday, took part in the 50-mile ÖTILLÖ race in Stockholm - a challenging event which involves running and swimming a 50-mile route across 26 of the Stockholm archipelago's 1000 islands

The Duchess of Cambridge's younger sister, who turned 32 on Sunday, took part in the 50-mile ÖTILLÖ race in Stockholm - a challenging event which involves running and swimming a 50-mile route across 26 of the Stockholm archipelago's 1000 islands

Although super fit Miss Middleton delayed birthday celebrations with her boyfriend and family, she was joined by (pictured from left) brother James Middleton, ex-boyfriend James Matthews and old friend Jöns Bartholdson - who were her teammates for the race on Monday

Although super fit Miss Middleton delayed birthday celebrations with her boyfriend and family, she was joined by (pictured from left) brother James Middleton, ex-boyfriend James Matthews and old friend Jöns Bartholdson - who were her teammates for the race on Monday

Pippa Middleton waves the Union Jack flag with Swedish friend and teammate Jöns Bartholdson after completing the 'swimrun' race, thought to be one of the most gruelling in the world

Pippa Middleton waves the Union Jack flag with Swedish friend and teammate Jöns Bartholdson after completing the 'swimrun' race, thought to be one of the most gruelling in the world

She managed to raise a smile and even wave to onlookers despite the challenging conditions, finishing in 13 hours, four minutes and 24 seconds.

Contestants must run wearing a wetsuit and are not allowed to remove their trainers for the swimming sections - all of which involve a dip in the notoriously chilly Baltic Sea.

Miss Middleton is no stranger to fitness challenges and said she was 'inspired' by the idea of taking part in an interview ahead of today's event.

'I'm inspired by the scenery, the sense of adventure and sheer distance that's involved - running 65km in a wetsuit and swimming 10km in trainers with hand paddles,' she told news agency Reuters.

'It's relentless. Almost three Ironman swims and one and a half marathons. Much of the running is trail running on uneven ground, hopping over rocks on the shore line, dipping in and out of bays.' 

Miss Middleton, who was one of 240 competitors, was also spotted practicing for the race during her recent St. Barts vacation. 

Miss Middleton was one of 240 competitors in the event
It involved running 65km in a wetsuit and swimming 10km in trainers with hand paddles

Miss Middleton was one of 240 competitors in the event, which involved running 65km in a wetsuit and swimming 10km in trainers with hand paddles. She manages to raise a smile despite the challenging conditions

Miss Middleton helps teammate Jöns out of the notoriously chilly Baltic Sea
She swims in open water with the aid of her paddles

Miss Middleton helps teammate Jöns out of the notoriously chilly Baltic Sea, left, for the event - which she described as the equivalent of 'almost three Ironman swims and one and a half marathons'. She swims in open water with the aid of her paddles, right

Speaking ahead of the event, Miss Middleton said: 'Much of the running is trail running on uneven ground, hopping over rocks on the shore line, dipping in and out of bays'
She was raising funds for the Michael Matthews Foundation

Speaking ahead of the event, Miss Middleton said: 'Much of the running is trail running on uneven ground, hopping over rocks on the shore line, dipping in and out of bays'

Miss Middleton's joy is obvious as she crosses the finish line with friend Jöns Bartholdson and brother James Middleton. The trio were raising money for the Michael Matthews Foundation, which builds schools in poverty-stricken locations around the world

Miss Middleton's joy is obvious as she crosses the finish line with friend Jöns Bartholdson and brother James Middleton. The trio were raising money for the Michael Matthews Foundation, which builds schools in poverty-stricken locations around the world

Miss Middleton competed alongside brother James, who was partnered with her ex boyfriend James Matthews, and friend Jöns Bartholdson. She finished the race in 13 hours, four minutes and 24 seconds

Miss Middleton competed alongside brother James, who was partnered with her ex boyfriend James Matthews, and friend Jöns Bartholdson. She finished the race in 13 hours, four minutes and 24 seconds

During the event, she was not permitted to be further than 50m on land and 5m in the water from Mr Bartholdson who also joined her for the Race Across America in 2013.

The pair, who were not expected to be joined by the Middleton family or Miss Middleton's boyfriend Nico Jackson, 37, were raising funds for the Michael Matthews Foundation.      

It was founded following the death of Mr Matthews, then 22, in a mountaineering accident on Mount Everest in 1999 and builds schools in poverty-stricken locations around the world.

The charity is run by members of the Matthews family, among them James, an ex-boyfriend of Miss Middleton's - who also competed in the race - and Made in Chelsea lothario Spencer.

James Matthews was also with the Middletons in St Barts, where his family owns the Eden Rock Hotel, and was seen splashing around with Miss Middleton and her brother during the trip.

The race started at 6am this morning and Miss Middleton told Reuters that she expected to take around 12 hours to complete the course. 

Pippa Middleton is no stranger to sporting events after taking part in the GE Blenheim Triathlon at Blenheim Palace on June 4, 2011,
Getting involved: Pippa also did the London to Brighton bike ride for the British Heart Foundation in June

Pippa Middleton is no stranger to sporting events after taking part in the GE Blenheim Triathlon at Blenheim Palace on June 4, 2011, left, and the London to Brighton bike ride for the British Heart Foundation in June this year

Boyfriend Nico Jackson was not expected to be in Stockholm to watch the race. The couple are pictured at the men's final of Wimbledon this July

Boyfriend Nico Jackson was not expected to be in Stockholm to watch the race. The couple are pictured at the men's final of Wimbledon this July

Speaking ahead of the event, she said: 'For our team, we estimate it will take us at least 12 hours non-stop swimming and running in unknown territory and conditions.

'We won't give up unless we risk long-term injury, so it will be a huge test of our resilience and grit, managing our highs and lows throughout the day.'

Miss Middleton certainly has plenty of experience of that, having completed a number of sporting challenges in recent years.

Along with the Race Across America, she has also taken part in the gruelling Engadin Ski Marathon, the GE Blenheim Triathlon and the Bosphorous Cross-Continental Swim.

Most recently, she cycled the 54 miles between London and Brighton on behalf of the British Heart Foundation, of which she is an ambassador. 

She is often spotted running through Central London, heading to her local gym or cycling in the countryside near her parents’ Berkshire home.

She recently said: ‘Exercise is a massive part of my life and a very personal thing for me; it’s so important for both the mind and body.’

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