Bigger Leaner Stronger: The Simple Science of Building the Ultimate Male Body

by Michael Matthews

The human body is about 60 percent water in adult males and about 70 percent in adult females. Muscles themselves are about 70 percent water. That alone tells you how important staying hydrated is to maintaining optimal levels of health and body function. Your body’s ability to digest, transport, and absorb nutrients from food depends upon proper fluid intake, and staying hydrated helps prevent injuries in the gym by cushioning joints and other soft-tissue areas. As you can see, when your body is dehydrated, just about every physiological process is negatively affected. To avoid dehydration, the Institute of Medicine reported in 2004 that women should consume about 91 ounces of water—or three-quarters of a gallon—per day, and men should consume about 125 ounces per day (a gallon is 128 ounces).90 Now, keep in mind that those numbers include the water found in food, which accounts for about 20 percent of the water in the average person’s diet. I’ve been drinking 1 to 2 gallons of water per day for years now, which is more than the Institute of Medicine’s baseline recommendation, but I sweat a fair amount when I exercise and I live in Florida, which means even more fluid loss through sweating.