Don’t roll your eyes at the guys in the gym who carry around the gallon-sized water jugs. You might be joining them. Water is necessary for life and we know that endurance geeks need a ton of it, but it turns out that water can even be considered anabolic.
A study from the Journal of Applied Physiology took seven bodybuilders through a squat routine in three different stages of hydration. When the athletes were dehydrated, they experienced a significantly higher cortisol burst after training as well as a slightly blunted release of testosterone and growth hormone.
This builds on research that has shown that fat cells release fatty acids more easily and muscle cells burn less protein when the body is fully hydrated. So do whatever you have to do to get your H2O in for the day, even if it means carrying that meathead water bottle.