Five marathons, zero calories, the power of fat adaptation | With Alex McDonald

In this week’s episode, I sit down with Alex McDonald – the first person in the world to complete five marathons in five consecutive days, completely fasted. Only water and salt. 212 kilometers (132 miles) – without ever having run a marathon before. In a world where carbohydrates are seen as essential for endurance performance, Alex chose a different path. His journey isn’t just about fat adaptation – it’s about discipline, metabolic flexibility, and the ability to trust the body’s built-in capacity. It’s exactly the kind of functional lifestyle and human potential I’m deeply curious about exploring:

What happens when we strip away the excess and build resilience from the ground up?

We talk about:

• Completing 5 marathons in 5 days with zero caloric intake

• Fat adaptation and metabolic endurance

• Mental clarity under extreme physical stress

• Challenging established truths in nutrition

• Resilience – both physical and mental

🌐 http://www.ketomarathons.com

📸 https://www.instagram.com/ketomarathons/

👉 Listen to the episode wherever you get your podcasts:

https://linktr.ee/theprimalswede

https://shows.acast.com/the-quest-podcast

Stay strong,

Erik

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Note: The Quest Podcast is primarily in Swedish, with occasional episodes in English.

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🎬 Watch and subscribe on YouTube

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🔗 Follow Alex McDonald

Instagram: https://www.instagram.com/ketomarathons/

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LinkedIn: https://www.linkedin.com/in/theprimalswede/

🌏 Talks & projects:

https://www.theprimalswede.com

🗺️ About The Quest

The Quest is a podcast about human potential—conversations with people who push their mental and physical limits. Ultra-endurance, adventure, health, and what it takes to grow beyond comfort.

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