And the pope's religion is... ?
Seriously, people write reports on this crap.
It's been known for years that a break from work improves concentration; doesn't matter what sort of break.
When I were a lad, one of my school teachers said that he'd not preach the same thing for any more than 20 minutes because after that people switch off; changing the subject 15 minutes in regains peoples attention... I thought it was arbitrary at the time, but whenever I noticed myself switching off was 20 minutes into each lesson!
So, a 2 minute break every 15-20 minutes will do wonders for your productivity.
Now, where do I send my invoice?