Colin O'Brady pictured on day 37 of his estimated 65-day-long odyssey across the Antarctic.

Colin O'Brady has just achieved something incredible. He has become the first person ever to ski across Antarctica solo, unsupported and unaided. The 33-year-old world record-breaker completed the mammoth expedition across the frozen land mass in just 54 days, reaching the finish line late on Boxing Day. O'Brady shared his achievement Wednesday via his Instagram account, which he has been regularly updating with a satellite phone to document his mission. "FINISH LINE!!! I did it! The Impossible First," O'Brady wrote.

It's an achievement the young American has been working toward for several years after turning to extreme sports to recover from a freak accident which left doctors wondering whether he would ever walk again. The ex-financier quit his job in 2008 to pursue sports full-time, reaching Olympic triathlon level and breaking the "Seven Summits" world record. But this Antarctic crossing has been his toughest challenge to date. Several others have died making the attempt. O'Brady, who calls his mission "The Impossible First,'' set out on Nov. 3 and became the 29th person ever to reach the South Pole solo and unaided on Dec. 13, 40 days into his journey. However, the final leg of O'Brady's journey was almost undoubtedly his most difficult: The extreme athlete completed the final slog of his almost-two-month mission with an epic 32-and-a-half-hour-long trek, which started early on Christmas Day morning and finished on Boxing Day. In that period alone, he covered approximately 80 miles. O'Brady described the final push as "some of the most challenging hours of my life." Yet he also said they also gave him a chance to reflect on the "profound lessons" he had learned during his journey. CNBC Make It took a look at those learnings and how they can be applied to other — less frosty — walks of life.

Learning to embrace loneliness

O'Brady's challenge saw him away from not only his wife and family but other human support for almost two months. Even after reaching his midway point — the South Pole — he had to avoid the hospitality of researchers stationed there in order to stay true to his mission of an unsupported crossing. That takes strength of character and the ability to embrace loneliness, even in times of difficulty. "I'm still just all alone camped out in this white nothingness ... It will be very strange after all this solitude to see signs of life tomorrow," O'Brady wrote on Day 39, three miles away from the South Pole. "I can't go inside, of course ... I must maintain my full atoning despite my proximity to civilization."

Finding inspiration in others

As O'Brady battled with his ultimate challenge, he looked to others' great accomplishments as a guide. That included drawing inspiration from his idol, singer-songwriter Paul Simon, and listening to his Grammy Award-winning album "Graceland" on repeat. O'Brady considers the album a life's achievement, so he was delighted on Day 35 when Simon called him for a chat. "We talked about many things, but setting aside celebrity and fame, what struck me most was talking to him about his process of creativity and bringing a masterpiece like Graceland into the world," O'Brady wrote.

Colin O'Brady celebrates in the snow. Colin O'Brady, Instagram

"I'm always so fascinated to talk to people who have worked their whole lives and put their heart and soul into striving for their highest performance, no matter the craft or canvas. Though his expression is music and mine endurance sport, we both could relate so much on the mindset required to attempt to perform at that level."

Celebrating small successes

O'Brady's mission required long days and often monotonous tasks to reach the finish. On Day 34, he wrote that the experience reminded him of a saying he would draw on during his pro triathlon days: "Chop wood, carry water." "It refers to the daily consistency required for success," O'Brady wrote. "It's nonstop work out here from the second I wake up in the morning, packing up, then pulling for 12 hours, just to get to camp and have to set it all up again to get ready for the next day." After all the training is done, it comes down to putting the motions into action, he noted. "Consistency is king and the key to success."

Colin O'Brady pulls his sleigh through the snow in the Antarctic. Colin O'Brady, Instagram

Taking time for gratitude

On Thanksgiving — Day 20 of his expedition — O'Brady wrote of the power of gratitude and its ability to provide perspective in hard times. Though he spent the holiday away from home this year, he continued an old family tradition from the depths of the South Pole and highlighted the things he was most thankful for. This year, that was his wife, Jenna, his health, and a clean pair of socks — the first item of clothing he had changed since setting out.

Colin O'Brady throws a pot of boiling water into the air in the Antarctic, creating "Antarctica Fireworks." Colin O'Brady, Instagram

Helping to inspire others