My friend Nate ran the Chicago Marathon. A few miles in, someone stepped on his ankle. He had every reason to stop. Nobody would have questioned it.

He finished anyway.

This is the first episode of Sisu Lab and it starts with Nate's story, because it's the story that started this journey for me. In it, Dr. Yvann Karamoko introduces the idea behind the podcast: that most people don't quit because they can't continue, but because they find a reason good enough to justify stopping. And that the distance between who you are and who you're becoming lives entirely in what you do with that moment.

This is what sisu is and this is why it matters.