Julio Mamute competes in the 10km event at the 2026 Great Wall of China Marathon. Photos by Julio Mamute

On Oct. 25, the Brazilian runner crossed the finish line of the Great Wall of China Marathon, completing a challenge he described as "the most grueling physical trial" of his journey. For a man who was once unable to take two steps on his own, completing a race on this iconic landmark carries meaning beyond a sporting achievement

"I run to save my life. I run to live," Mamute told the South China Morning Post.

Unlike previous races held on paved roads, the course in China required Mamute to navigate 4 km of rugged trails filled with stones and obstacles, before tackling a 700m stretch of steep, rugged stone steps at the Great Wall.

"And I don’t climb alone. I carry the weight of at least three adults. For me, every step is a mountain," Mamute added.

Throughout the eight-hour struggle, he carried a special source of motivation. Visiting China had been a lifelong dream for his father, who passed away in 2024 before witnessing his son’s successful weight-loss transformation.

"If I could speak to him now, I would say: ‘Dad, we made it,’" Mamute said.

The journey to run again

Just a few years prior, completing this challenge would have seemed impossible. At his heaviest, Mamute weighed over 310 kg and was confined to his bed. He relied on a continuous positive airway pressure (CPAP) machine to sleep. When a power outage caused the device to fail, Mamute began to suffocate, feeling like he was on the verge of death. However, even the fear of dying failed to make him change.

The turning point arrived on Nov. 13, 2023. His first nephew was born prematurely at exactly 11:30 p.m., the exact time Mamute had been born 32 years prior. He felt it was a powerful sign that life was still worth living.

A week later, while arriving to deliver a gift to his newborn nephew, Mamute found himself physically unable to step out of his car, despite using a walking cane. The feeling of helplessness triggered action. He signed up for an exercise class underwater that very same day.

Mamute’s obesity had developed over many years. Although he was a slender and active child who loved swimming, his weight began climbing at age 11 despite having no family history of obesity or known psychological trauma, according to Brazilian news site G1 (Globo).

Julio Mamute at his heaviest weight of over 310 kg. Photo by Julio Mamute

By age 15, he had started his own business, frequently working through the night and neglecting his health. At 18, his weight went up to 180 kg. By his early twenties, he approached 200 kg, forcing him to purchase two airplane seats every time he traveled.

Despite doctors advising surgery, Mamute's daily habits worsened. Staying up late and lacking dietary control worsened his weight gain. During the Covid-19 lockdowns, he gained an additional 100 kg, pushing his total weight past the 310 kg mark, Marca reported.

Before turning to exercise, Mamute tried various weight-loss methods with medications like Ozempic, Saxenda and Mounjaro, and even had a gastric balloon inserted to limit his food intake. However, his binge-eating habit continued until the balloon eventually popped inside his stomach, requiring a hospital visit for removal. That terrifying incident made him realize that medical solutions could not fix a problem deeply rooted in psychology.

Because of his extreme weight, running or walking posed a risk of severe joint injury. Mamute therefore returned to his childhood passion of swimming.

He started with gentle underwater movements before rapidly progressing to swimming twice a day. The aquatic environment reduced the physical load on his joints, allowing him to remain active without pain. He estimates that swimming accounted for nearly 100 kg of his total weight loss, while also curing his severe fatty liver condition.

Mamute has been openly documenting his struggle on YouTube and Instagram, amassing more than 3 million followers.

His recovery journey faced massive hurdles, according to his channels. In 2024, the back-to-back deaths of his father and a close uncle caused Mamute to relapse into eating uncontrollably. He regained 30 kg, later admitting he was destroying himself all over again.

To overcome this dark period, Mamute turned to his faith, family support and a special charitable commitment. He linked his weight-loss progress to a food-donation activity for poor families, successfully giving out over two tons of food across Brazil and abroad.

Mamute also delved into neuroscience to change his understanding of compulsive eating. He realized that repetitive behaviors become deeply ingrained habits within the brain and cannot be simply erased in a day or two.

Julio Mamute crosses the finish line of the 10km race at the Europe Marathon in Aveiro, Portugal, in April 2026. Photo by Julio Mamute

In January 2025, Mamute began posting videos documenting his weight-loss journey on social media. At the moment, his accounts boast around 5 million followers and garner tens of millions of monthly views.

One of the first videos to gain attention captured passengers on a plane openly negotiating to avoid sitting next to him. Instead of getting upset, Mamute turned the awkward situation into a humorous, self-deprecating story.

However, he remains focused on impact rather than fame, recalling how his daily updates convinced a young woman in despair to abandon her suicidal intentions.

Once completely unable to walk on his own, Mamute has now participated in long-distance races across the globe.

In the 10 months leading up to his Great Wall challenge, he completed a 15.8 km run in São Paulo, a 10 km event at the Europe Marathon in Portugal, and competitive races in Argentina and Brazil.

His long-term goal is to drop below 100 kg, undergo surgery to remove excess skin, and travel to Greece in November 2028 as he aims to complete a full marathon along the historic route from Marathon to Athens while producing a feature documentary about his self-transformation journey.

"Obesity stole many things from me, and it almost stole my life," Mamute said in his podcast. "Human beings were born to run. I’m here to prove that it’s possible to get out of that dark swamp, out of that quicksand, out of that cave. I choose life. I choose to live."