Sex—and smooching and snuggling and everything else on the spectrum—is great for your relationship and happiness, but intimate time with your sweetie is also terrific for your physical health. Not only does that "loving feeling" get your heart rate up, it can burn some serious calories, too! Check out the calorie-burning profile of each romantic activity below (based on the body weight of a 150-lb woman) along with tips from experts on ramping things up to maximize the amount of calories burned.