As the Wolverine, actor Hugh Jackman made the contours of his muscles, veins, and bones pop out by intentionally becoming super-dehydrated for 36 hours before shooting shirtless scenes.
That’s risky business. In 1992, 33-year-old professional bodybuilder Mohammed Benaziza died following a competition when severe dehydration caused heart failure.
Even if you don't collapse, repeatedly making yourself dehydrated can cause long-term reduction in muscle strength.
Unintentional dehydration is just as risky. And it can sneak up on you, especially in the summer.
One study in the American Journal of Public Health found that half of kids don't get adequate hydration, and the Centers for Disease Control and Prevention says American adults only take in about 39 ounces of water daily (that's around three tall glasses), which is not nearly what's needed to keep your bowels, kidneys, and heart happy.
Add to that temperatures in the 80s and above and — we hope — an hour of aerobic exercise, and you could be 40 to 80-plus ounces short of what you need.
Signs of a dehydration crisis include dizziness, fatigue, confusion, headache, and less volume or darker urine.
Unfortunately, by the time you're thirsty and have a dry mouth, you're already starting to dry out inside. Your best bet is to drink 16 ounces of water first thing in the morning and then drink a glass of water (not some sugary soda or sports or energy drink) every couple of hours during the day.
When you exercise, drink every 15 minutes, outdoors or in the gym. And remember to have a glass of water after every alcoholic beverage.