This is a 2007 book by Haruki Murakami of his thoughts and experience on running.
The style is like an essay, but he prefers the word "memoir".
Murakami began running when he was 33 years old and has completed a number of marathon races until today.
In this book, he describes how he decided to begin running, the first marathon in Greece, challenges he faced, and so on. He says he is determined to continue running no matter how he gets old and how his record becomes worse.
I find the part particularly interesting where he mentions the relationship between the age of artists and their ability. He writes something like this: The peaks of professional swimmers come when they are early 20s, but fortunately the ones of artists substantially vary. Fitzgerald wrote The Great Gatsby at 29, whereas Dostoevsky wrote his most important two novels, Demons and The Brothers of Karamazov in his 50s and when he was in his closing years.
As I read Murakami's first book in three years (the title is literally The colorless Tsukuru Tazaki and the year of his pilgrimage in English), I was thinking which one future critics would think the best for Murakami's works.