It turns out, "Her Royal Hotness" is also a serious competitor, currently in between training for a handful of downright badass fitness challenges.

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Pippa Middleton is currently taking some well-deserved time off, vacationing in St. Barts and showing off her slamming bikini body—ah, the rough life of a "nearly royal."

Yes, our first reaction was a bit of sarcasm, too. But it turns out, Middleton is in between competing and training for a number of downright badass fitness challenges.

Sure, naysayers may still balk at her accomplishments, throwing out things like, “she has all the time in the world to train—does she even work?” (For the record, she’s the editor of The Party Times, a blog from Party Pieces, the party supply store founded by her parents.) Or, “she can hire anyone she wants to whip her into shape!” But the thing is, you can’t pay someone to cross a marathon finish line for you or swim from island to island in Sweden...more on that later. These are the kinds of things that take grit and determination—something the Duchess of Cambridge's sister seems to have no shortage of. Here are five things that really impressed us, including what she's doing next.

She ran a high-altitude marathon in Africa…a week after a 54 mile bike race

What do you do after you bike 54 miles for charity? If you’re like Middleton, a week later you head to Kenya and compete in the Safaricom Marathon. Because of the high altitude on this course (5,000 ft.), the air is much thinner, making it that much harder. Despite the tough conditions, she crossed the finish line this June in less than four hours. The event raised money for Tusk, a wildlife protection and sustainability charity in Africa. (Prince William is a “royal patron.”)

She biked across America

Plenty of folks have a cross-country road trip on their bucket list, but they usually mean driving it, not biking it. Last June, Middleton participated in the Race Across America, a 3,000-mile relay ride from Oceanside, California to Annapolis, Maryland. Her team, which included her younger brother James and friend James Matthews traversed the Rockies and Appalachians to raise money for the Michael Matthews Foundation, which builds schoolhouses in countries that may not be able to afford them.

She keeps competing in the winter

Back in 2012 Pippa completed a whopping 56-mile cross-country ski race in Mora, Sweden (her brother also skied with her), facing sub-zero temperatures, and finishing the race in just over 7 hours. That was her first introduction to cross country racing, and so naturally a year later she did another race, ticking off the Engadin cross-country ski marathon in Switzerland, and finishing the 26.2 miles in under three hours.

She ran a “fell” race

You’ve got to be in hella good shape to run a fell race (“fell” is the term for rugged, remote terrain in the U.K.). So no doubt, Pippa competed in one—the Highland Cross in Scotland, just a couple of months after her sister’s wedding. The race includes a 20-mile rocky, muddy off-road run, followed by a 30-mile bike ride, which she completed in a little over five hours—finishing an impressive 12th out of 150 women.

Her next challenge: the Ö TILL Ö Swim-Run Race

In just a few weeks Pippa will compete in the Swedish Ö TILL Ö Swim-Run race, where teams of two people swim between 26 islands, and then run over them (!). No big deal. The course makes for a total of 75 kilometers of action—with 10 kilometers of open-water swimming, and 65 kilometers of running, according to the event web site. And all of that must be completed from dusk till dawn. On top of that, Pippa will be fundraising once again for the Michael Matthews Foundation.

Now off to start Googling fell races—or see if that Swedish swim-run is still accepting entries for 2016. (Just kidding, no way we're ready for that yet.)