Remember the old Nike strap line way back when she'll suits were cool! - just do it!
I can only presume that these guys were decades ahead of their time or they did not quite comprehend the power of their own mantra.
You see, when we lack motivation what we are actually experiencing is an emotional low. This can be brought on by being mentally tired, bored, fed up, apathetic or even moderately depressed but you get the picture.
These emotional states are borne of a complex balance of our bio-chemistry and neurophysiology. It sounds very complex but actually could not be much simpler! The sheer act of doing something and I mean anything changes this balance and with it your emotional state.
How many of you reading this right now can relate to that internal argument you have with that little voice inside your head about doing something. Yeah sure it could be about going to the gym but it could just as easily be about a personal, business or social commitment.
You can think of a million reasons why not to do it with very little effort, but on the rare occasion you do not succumb to these thoughts and just do it-how good do you feel when the task is complete? Fantastic if you are anything like me.
The point is you just got on and did it. You didn't succumb to your self validating negative thought processes.
So instead of enduring the mental torture of all the reasons why you shouldn't go ahead and do something from that little voice inside your head, how about next time you feel a lack of motivation you get on and "just do it".