How long do the effects of being grounded last?
How long the effects of grounding last in your body depend on your body's electrical state.
It's ideal to be grounded all the time because just being alive uses up electrons in many metabolic processes, including the basic process of cellular energy production. There is always an ongoing demand for electrons, which you receive from grounding.
When you ground yourself on a routine basis, you are, in a sense, topping up your electron tank which maintains the electrical stability of your body.