Drinking enough water has so many benefits. Water can boosts mental and physical performance according to a recent study. When you’re properly hydrated, the whole body just operates far better. When you train in the dojo, always have some water with you.
I use a simple plastic bottle, which I buy new once in a while and refill it with tap water. The bottle lasts me up to 3 months, tap water at our place is best to drink and the cheapest. In general, even without training, drink at least 10 glasses of water a day.