How You Burn Calories
While simply living will cause your body to burn calories, the best way to burn off energy is to move--to exercise. Swimming burns lots of calories (about 475 an hour, according to caloriesperhour.com) because it causes the body to use muscles and aerobic skill to move through the water. The more you move, the more muscle power you use, the more calories you burn.
Other Ways To Burn Calories
Different bodies burn calories at different rates. The difference is in the metabolism, or the calories burned to keep your body's basic functions going. People with fast metabolisms process food quickly and burn more calories than people with slow metabolisms. Exercise is the best way to boost metabolism, but other things can cause a slight uptick. Increasing body temperature is one of those ways.
Hot Tub Calorie Burning
In an interview with the Los Angeles Times, John Porcari, an exercise and calorie expert at the University of Wisconsin, estimated that a 150-pound person would burn 34 calories during 20 minutes in a Jacuzzi--about the same as taking a bath.
By comparison, the same person would burn about 100 calories in 20 minutes simply by walking slowly, he said.
Larger people require more energy to move, so they burn more calories. But experts such as Porcari do not recommend hot tubs as an effective way to lose weight.
While a hot tub is comfortable and relaxing, health experts recommend using them for no longer than 15 to 20 minutes at a time. It may be tempting to think that sitting in a hot tub for an hour burns the same amount of calories as running a mile (about 100), the fact is that sitting in a hot tub for an hour is unsafe.