This is a curious result that apparently (unlike some other things in psychology) is repeatable: People given a task requiring creativity (such as coming up with as many ways as possible to use paper cups) tend to do better if they've previously been doing something boring. I wonder if this is why meditation seems to help.
Update: I screwed up and used a link to the wrong video above, unintentionally insulting an innocent party. I've corrected it above. Below is the video I originally linked to, even though it's not really on-topic.