Servo motor messes up electrical input

I am working on building a single servo powered arm that is controlled by Backyard Brain's muscle spiker shield. It measure the electrical signal in your muscles and converts it to an input. This works great with leds, however, as soon as I connect the servo (without even including servo in the code) the input immediately jumps extremely high and cannot be read. I think this is because the servo divert electricity. Has anyone found a solution around this sort of thing? Maybe separately powering the servo? Thanks in advance!

themc1r: Maybe separately powering the servo?

You answered your own question. I think powering the servo separately is the way to go.