kickstarting brain performance?

Have you ever noticed dramatic changes in your performance?  So that one week you win game after game and chess flows- and then the next week you couldn't even beat anyone?

I notice that when things click for me there is something like a song that plays and the pieces move in my head. But When I can't play there is this dull silence in my head and I can't force myself through it.  

Anyone know of tricks to kickstart brain to wakeup and analyze? 

routines are good before a club match i walk in the park and this seems to work for me as i leave any mental pressures there funnily enough being a captain gives me more brainache when i get there lol

 I identify 100% with this siruation,to add I all I would say that during this bad episode I become frustated and start losing game after game and this further adds to my frustation and viscious circle sets in. I think this happens when one has played too many games and this puts extra pressure on brain specially when you have others thinkgs in mind our brain is like a computer when so many tasks are performed it sometimes hangs. During this situation I think best think to do is just stop playing and restart your brain by diverting your mind to some pleasureable things like fantasising a date or even having a cup of coffea. However this is my opinion and I dont know how big players are trained for maximum efficiency

Sleep more