Hypothetically, if the threshold is normally -60mV, but now we have too much calcium on board, our threshold is now -50mv. That is a difference of 40mV that the cell has to account for in order to depolarize. In skeletal muscle, this can cause weakness, fatigue, etc. Too little calcium will cause the threshold to become more negative (gets closer to the resting membrane potential).
OK, this is probably going to come with you laughing at me... Once in a while I wake up with the back of my head sweating, and it`s more common when I take a nap during the day.
When we're hot and we sweat, that moisture evaporates and cools us off a bit. And we don't just sweat when we're hot. It's also normal for people to sweat when they're nervous because emotions can affect the sweat glands. Sweating is one part of puberty. When our bodies starts to change, roughly 3 million sweat glands become more active. This is especially true for glands in the armpits and groin and on the palms of the hands and soles of the feet.