Is it possible to get stronger just by thinking about exercise?

Source BBC:

Could simply thinking about exercise – without so much as lifting a finger – really do the trick?
It sounds incredibly unlikely, but ‘motor imagery’ is a technique often used by top athletes, and some studies suggest that you can use it to improve your strength by mental training alone.
Trust Me, I’m a Doctor teamed up with The University of Northampton’s Professor Tony Kay to put this wonderfully weird idea to the test  Read on