I ask because sometimes I can do 40V at the same pulse width and the Hidrex shows 2mA and other times it shows 22mA. It seems to vary quite a bit, and I realize that's because my own body resistance can change pretty quickly. But is it the voltage that matters or the current? If during a session, I'm noticing the mA is staying low, should I raise the voltage to try to get that mA back up? Are sessions where I'm at 40V and 2 mA not as good as 40V and 22mA?