Potential energy is what is stored to be used, but not used yet. If you are on a skateboard at the top of a hill, you have potential energy. As you start going down the hill, you have less and less potential energy and more kinetic energy.
This is also in the human body. Food is chemical energy. As your body breaks down the food, it is being turned into another form of energy, potential energy. Then when you go and run or do an activity, that potential energy is being used and it is being turned into kinetic energy.
