Forty-seven days ago, Mohamed Lahna dived into the waters around Manhattan. On Wednesday (29 July), the three-time Paralympian crossed the finish line at Venice Beach after swimming, cycling and running 3,300 miles across the United States in what is believed to be the first triathlon of its kind completed by an athlete using a prosthesis.

Born with proximal femoral focal deficiency – a rare congenital condition that left him without a right femur – Lahna has built a career around taking on some of endurance sport’s toughest challenges. After receiving his first functional prosthesis at the age of 20, he rode a bike for the first time at 25, cycled across Morocco’s Atlas Mountains at 26 and completed his first marathon at 27.

Since then, he has raced the Marathon des Sables, swum the Strait of Gibraltar, competed at the Ironman World Championship in Kona and become the first – and still only – adaptive athlete to earn the coveted black T-shirt at Norseman Xtreme Triathlon. He has also won Paralympic medals representing two nations, claiming bronze for Morocco at Rio 2016 before taking silver for Team USA at Paris 2024.

Yet even those achievements pale in comparison to his latest endurance feat – here’s why…

A 3,300-mile journey across America

Lahna’s challenge began on 13 June with a 28.5-mile swim around Manhattan Island, completed in seven hours, 44 minutes and 58 seconds. From there came a bike leg unlike any other. Approximately 3,000 miles from New York City to Las Vegas, crossing 16 states, climbing more than 100,000 feet and passing through forests, plains, mountain roads and desert terrain.

Along the way, he battled extreme heat, strong winds and smoke from nearby wildfires, yet still reached Las Vegas three days ahead of schedule. But after weeks in the saddle, the biggest test was still to come.

Transitioning from cycling to running is difficult for any triathlete. For Lahna, it meant asking his body to adapt from weeks of high-volume riding to a 300-mile run on a prosthetic leg through the Mojave Desert.

“This has tested every part of me,” Lahna said. “It tested my body, my mind, my patience and my ability to keep believing when things became difficult.” The final stage exposed him to relentless desert temperatures, exposed roads and long stretches of soft sand, placing immense pressure on both his prosthesis and residual limb.

“The run through the Mojave Desert was incredibly tough,” Mohamed Lahna added. “The heat was relentless, and running through soft sand with my prosthetic leg demanded an enormous amount of energy. Every step shifted underneath me, and the pressure on my body and my residual limb was extremely difficult to manage.

“I battled blisters, boils and constant pain. There were times when we had to stop, treat the wounds, adjust the prosthesis and find a way to continue. Each morning, I knew the pain would still be there, but I also knew why I was doing this.”

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Raising money for the next generation

The Triathlon Across America wasn’t only about breaking endurance barriers. Growing up in Morocco, Lahna attended an elementary school funded by Save the Children. Later, after moving to the United States, the Challenged Athletes Foundation gave him access to a community and support network of athletes with physical disabilities.

The challenge is raising money for both organisations to help them continue providing opportunities for children and people with physical disabilities. So far, more than $166,000 has been raised, with a target of $250,000.

“There were moments when my body was telling me to stop,” Lahna said. “But I kept thinking about the children and athletes we are trying to help. I kept thinking about the people who had donated, the team beside me and my family waiting at the finish. That gave me a reason to take the next step.”

Lahna reached Venice Beach shortly after 1pm on 29 July, bringing his 47-day journey to an end – becoming the first athlete with a prosthesis to complete a triathlon across the United States.

“I am incredibly proud and grateful to have reached Venice Beach and completed this journey,” he said. “There were so many moments when the finish felt impossibly far away, but my team, my family and everyone who supported us gave me the strength to keep moving forward.”

The challenge may now be complete, but Lahna’s endurance career is far from over. With his sights firmly set on the Los Angeles 2028 Paralympic Games, the Paralympian will hope his latest extraordinary feat is another step towards a first Paralympic gold medal.

To find out more about Mohamed Lahna’s Triathlon Across America challenge or make a donation, visit the official fundraising page.

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