this is one of the biggest scams we see out there. we were always taught growing up that you must drink water and you need to hydrate blah blah blah.. if you play sports you must hydrate or you will die!
the bottom line is many athletes OVER hyrate. did you know 1/4th of marathon runners actually finish the marathon weighing MORE than they started? why? cause they drink too much during the race and do not urinate. so it ends up hurting you instead of helping
my advice if you are a runner or triathlete is SIP and spit during your race. do not drink!
aside from that a weight lifter doesn't need as much water as the sports drink companies want you to believe. you drink when you are thirsty. personally i will make sure i urinate prior to my workout and i will carry water with me and sip during my workout when i need to.
this idea that you need to drink a gallon of water a day is horseshit and is actually counter productive. the only time you would need that much water is if you sweat out a ton... dont listen to the scammer sports drink companies that push hydration as some sort of magical unicorn.