Last year, I walked 900km (560 miles) across Spain on a trail known as the Camino de Santiago. It’s a challenging enough adventure as it is, but what made things all the more difficult is that, three days into the walk, I felt an uncomfortable pinch in the back of my left heel.
At first, the pain wasn’t severe. It was just irritating — as if someone was lightly pinching the skin whenever I took a forward step — and I was mostly concerned about whether or not the pain would get worse.
Then it got worse.