It was the thought of his wife and two young daughters back in Quebec.
"Kite-skiing for 24 hours in extreme conditions is a challenge I love," he said after arriving back in Montreal on Monday.
"Putting up a tent in a blizzard is something I can do and have fun doing. But being far from my children and wife was my biggest difficulty."
Dion, 37, made the trip to the Antarctic on skis with the help of wind-sail.
Along the way, the native of the central Quebec town of Notre-Dame-du-Mont-Carmel fought winds of more than 100 km/h and suffered frostbite as he braved temperatures that often plummeted to -50 C.
He also broke his sleigh, which contained a tent, sleeping bag and food.
"The moment when I felt fear was when I lost my sled for 20 minutes," said Dion, surrounded by his wife, Caroline Mailhot, and their daughters, Adelie, 6, and Danaelle, 3.
"This was the worst moment, but I felt fear for 30 seconds. I rarely think 'Am I going to die?' and that event, for a small moment, it was pretty scary."
He ended his voyage at Hercules Inlet on Jan. 3, completing in 54 days and six hours the crossing of Antarctica that he began on Nov. 10 from the Russian Base Novolazarevskaya.
All told, he covered 4,382 kilometres in 54 days.
Being alone was not a problem.
"Solitude for me is not a prison," he said. "It's a secret garden. I had a great trip.
"The biggest challenge was managing the doubt in my mind and managing the separation from those I love — and that includes my wife and children."
He communicated with them only once a week during the bone-chilling excursion.
As to where he's headed next, Dion said his family will come first.
"The next big adventure — and it's one that will last several months and several years, and I know I have a lot of competition — is I want to be the best father in the world."
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