A recent book, The Runaway Species (http://www.drchrisharper.co.uk/blog/book-review-the-runaway-species), sparked an interest In creative thinking. Here is a nice little article discussing how just going for a walk can be scientifically demonstrated to increase creative thinking.
If you have a sedentary job make time to walk for at least 60 seconds every hour. This will not only help prevent general health issues but will boost mental function.
And if you are struggling to find a creative solution to a tough problem then take a 10 minute walk outside and then come back to the problem.
Dr Chris Harper