It's worth reading this article about the treadmill desk. Don't dismiss it as a novelty. Its an example of how an idea was born, implemented, how its usage changed over time and how the concept spawned a new idea -- the walking meeting.
Then Levine had another idea. If people could work while they were walking, why couldn't they have meetings as well? And so the concept of the walking meeting was born. His plan was that a designated walking track could be marked out in an office using carpet tape. Two people walking together could both wear coloured badges so that everyone else knew they were in a private meeting and shouldn't be disturbed.
... remarkably a Minnesota financial recruitment company called Salo heard about his ideas and decided to put them into practice ... "we found that walking meetings not only tended to be more productive than sedentary ones, they're also, on average, 10 minutes shorter."