Often times humans compare their energy levels to fuel in a car’s gas tank. People say, “I’m running on empty today,” and things like that.

So let’s stick with that analogy for a bit and turn you into two of the cars that I have owned in my lifetime: a Porsche Boxter and a 1979 Volkswagon Bug.

Let’s agree on two things: These cars are designed for different performance levels, and because of that they require different fuel grades. So, When I go to the gas station I have choices: anywhere from 85 to 94