GALLERY: Pippa Middleton's most impressive fitness challenges

06 Sept 2016, 11:51 BST

Pippa Middleton is no stranger to extreme sports - the Duchess of Cambridge's sister regularly takes on impressive fitness challenges from gruelling ski races to climbing the world's toughest peaks.

We take a look at a history of Pippa's incredible fitness achievements to date – click through for the full gallery…

In August 2016 Pippa conquered the Matterhorn, reaching the 14,691ft peak shortly after day break. It was a bittersweet achievement for the British beauty, who climbed the peak in honour of her fiancé James Matthews younger brother Michael, who died in 1999 while scaling Mount Everest.

"It was so humbling to have been able to climb one of the world's most beautiful mountains and raise money for a charity created in memory of an extraordinary young man who lost his life on another peak," Pippa later told the Mail on Sunday. "Although I have raised money in the past for the Michael Matthews foundation, it has now become even more important to me and my family."

Kate's younger sister showed off her skills in March 2016 when she completed the 54km (33-mile) Birkebeiner cross-country ski race in Norway. Speaking exclusively to HELLO! she revealed that before such a tough race she switches up her already healthy diet.

"I try to eat wholegrain, energy-fuelled carbohydrates and three meals a day," she told HELLO! exclusively. "I also increase my portion sizes based on my training level, with lots of brown rice, lentils, quinoa and sweet potato, and for breakfast, porridge and rye toast."

The extreme sports enthusiast proved she was a force to be reckoned with when she took on the world's longest downhill ski race in January 2016. The Inferno Cross Country ski race in Mürren, Switzerland, is a gruelling 15km downhill ski with a drop of over 2770 metres in altitude. Pippa placed 67th out of 105 competitors, completing the course in just 12 minutes and 28 seconds.

Sam Bichsel, a spokesperson for the event, told People: "She was a little bit nervous at the start because it was the first time she has done a race like this," he said, adding, "It’s one of the hardest races you can do in the alpine sport, almost 15km downhill and a little bit uphill too, it’s not easy!"

Never one to shy away from a challenge, in September 2015 Pippa took on the Otillo Swimrun World Championship in Sweden, along with her younger brother James, her fiancé James Matthews and the couple's friend Jons Bartholdson. The race features teams of two swimming about six miles in the frigid Baltic Sea followed by a 40-mile trail run – Pippa did herself proud, completing the course in 13 hours, 4 minutes and 24 seconds.

Photo: @otillorace

In July 2015, Pippa marked another milestone in her already impressive list of achievements as she completed her first ever marathon, choosing the 42km Tusk Trust's Safaricom Marathon in Kenya to make her debut. "I decided that a marathon was a 'life box' that needed ticking and this year was my time," she wrote exclusively for HELLO! at the time. "Despite it being one of the toughest in the world, with temperatures rising to more than 30ºC, at an altitude of 5,550ft and with the possibility of bumping into lions or rhinos."

She later added: "It was tough – tougher than anything I’d been faced with before and required every inch of my energy, stamina and stubbornness."

Pippa and her brother James helped to raise money for the British Heart Foundation in June 2015 when they took part in a 54-mile bike ride from London to Brighton. As a long-term ambassador for the charity, Pippa led the group of around 22,000 cyclists from Clapham Common in London to the finish line on the seafront in Brighton.

"The event is testament to the fact that cycling is such an inclusive sport that everyone can enjoy," she told the Brighton Argus after the race. "Through the money raised, the BHF can continue to help the millions of people affected by coronary heart disease – the UK's single biggest killer."

Prince George and Princess Charlotte's aunt triumphantly completed the Race Across America challenge in 2014, a gruelling 3,000 mile cross-country trip. She was joined by brother James for the trip, along with six teammates.

They cycled through 12 states in just six days, ten hours and 54 minutes, crossing the finish line in Annapolis, Maryland. Dressed in their Union flag-themed Lycra, they raised money for the British Heart Foundation and the Michael Matthews Foundation throughout their challenge.