Walking, no talking

It began as a bit of a joke. The writer and journalist Jon Mooalem started recording the walks he took near his home on a wooded island in the north western US. All you can hear on his podcast 'Walking' is the sound of his footsteps, and his breathing (plus the odd ad). But with some industry buzz and new listeners finding the show, people have started looking for meanings in what he's doing. Is 'Walking' some kind of mindfulness tool? Or with Jon's interest in nature, is it a coded environmental message? We speak to Jon Mooalem to find out.