Drink More Water
This sounds too good to be true, but it's legit. A 2003 study published in The Journal of Clinical Endocrinology and Metabolism found that study subjects burned up to 30 percent more calories after drinking 17 ounces of water. The study authors noted that most of this increase was likely a result of the body having to heat the water for digestion, so make sure you're drinking ice water for maximum effect.
"Water actually comes into play in a couple of ways," says Christy Kirkendol, MD, who specializes in weight loss at her Livelight Clinic in Indiana. "Cold water can help you burn more calories, but it also gives you that sense of fullness and helps you figure out whether you're 'stomach hungry' or just 'head hungry.'"
Plus, even being just a little dehydrated affects athletic performance, meaning you won't hit it as hard in the gym. A 2007 study published in Medicine & Science in Sports & Exercise found that dehydrated athletes performed single tasks just as well, but failed when asked to perform sets of exercises. So if you're planning to do more than one rep at the gym tonight, drink up.