A book in wish list

When I was running in the gym today, I was reminded of a book by Haruki Murakami, in which he wrote on his thought and experience on running.

I got anxious to buy one, so I checked online. But unfortunately, there was no electronic version available.
As I was browsing Amazon, I realized many of Murakami's translated novels were sold in Kindle edition, whereas none of them were on sale in Japanese. Does it mean Kodansha and Shinchosha are reluctant to offer electronic version?

Nevertheless, I've found his interview on running in 2005. The last two paragraphs are pretty interesting.

The most important qualities to be a fiction writer are probably imaginative ability, intelligence, and focus. But in order to maintain these qualities in a high and constant level, you must never neglect to keep up your physical strength.

Without a solid base of physical strength, you can't accomplish anything very intricate or demanding. That's my belief. If I did not keep running, I think my writing would be very different from what it is now.