Instrumentation should reflect emotion. Poetry should deliver something to think about. Good music combines these into something synergistically more powerful. If you complement the right mood with the right genera at the right time, music can be a catalyst that pushes you forward, leveraging your existing momentum and augmenting your efforts in whatever you are doing. At an objective level, some genres of music do this better than others because they tend to be more authentic and less commercial – the bastardization of country and pop are cases in point. Metal taps anger, rage and aggression. Blues taps sorrow, frustration, and sometimes joy. The niche labels within genres today almost get a little ridiculous, and in reality it comes down to the quality of the musicians, song writing, and producers. Typically I start with hard rock, metal, blues, and surrounding niche moods, but can move into a reggae, and even a folk (I know I know) mood when I’m dreaming about living on a beach drinking margaritas for a living. Of course, you can’t forget about caffeine. The perfect supercharge recipe (good can vary here depending on context): good mood + good music + stimulant = high productivity.
Just a note about authentic verses commercial music… I realize that all the music streaming through Pandora is intrinsically commercial. But there is a difference between music that is created by a member of a community, and refined for sale to that community, that reflects a common meaning within that community, and music that is created exclusively for mass sale and profit earnings (e.g., Metallica verses New Kids on the Block). In both cases you need to earn a profit margin to make the creation and distribution of the music feasible. But in the former case, the music seems to be less tainted by a need for earnings, and hence more authentic than the latter, where earnings is the principal objective and artistry is either non-existent or merely a means to the end.