Water is both healing, relaxing and rejuvenating. When you've had a full, busy day, there is nothing like relaxing with a nice how shower or bath. Not only will you feel better, you'll be more energized with out the side effects of those stupid energy drinks.
Likewise... There is no better feeling than jumping into a cool pool (or lake, or ocean) on a hot day.
It's a wonderful feeling as well as transformative for you physically, mentally and most of all emotionally.
Give it a shot!