First secret of good meditation is to avoid forcing the stream of thought. It's like a river.
Just like sleep, originally scientists thought meditation was like switching off the brain, instead they found the brain activity increase especially in prefrontal cortex, that's where our most complex thoughts are located.

Meditation is like turning the brain in a diagnostic phase, neural connections reorganize and thinking improve subsequently. Once, I was of the opinion meditation was a lost of time...today I changed completely ideas