Olympic swimming superstar Michael Phelps eats 12,000 calories a day. Think about that a moment. That’s more than you and me combined, and you and I are probably overweight. At least I am. Michael Phelps certainly is not.

How does Michael Phelps do it? Subway? I doubt it. Is it because he is almost constantly working out? Certainly that has something to do with it, but there is another level to all this that experts are saying comes into play.

Standard wisdom says that all weight loss, gain, and control in general is about two simple things: Calories in and calories out. That is to say, if you use more calories than you consume, you end up with a “calorie deficit” and start losing weight. Theoretically, 3500 calories equals one pound of human body weight. So if you have a 3500-calorie deficit, you lose a pound.

The addendum to this is that the body expends energy, calories, to do everything. This includes breathing, walking, jogging, having sex, etc. And one of the key things that it does is maintain your body temperature at a steady 98.6º.

And here is where Michael Phelps’ secret gets revealed. Standard swimming pools for folks like Phelps are usually around 80º. Now that won’t drop your core body temperature to 80º, but it will make your metabolism kick things up a notch as you exercise, just to try to return things to 98.6.

ABC News reported about Ray Cronise, a former NASA scientist who used the benefits of lowering his body temperature regularly to help supercharge his weight loss efforts. He lost 30 pounds in 6 weeks.

“The current paradigm of losing weight is diet versus exercise, calories in, calories out. What I was able to do was figure out that another big part is the environment we’re in. Our body temperature remains constant and it takes a lot of energy to keep it that way, no different than heating your house,” Cronise says. “I treated my body like a thermostat…to see if I could run up the utility bill and get the furnace, [my metabolism,] running at full blast.”

According to the popular LoseIt! app, used by many to track calories and exercise, 30 minutes of leisurely swimming, not laps, burns 439 calories. By contrast, 30 minutes of low-impact aerobics only burns 351 calories. And 30 minutes of leisurely bicycling would burn only 264 calories.

Michael Phelps works out 6 hours a day, 6 days a week, the vast majority of which is in the water. He probably burns somewhere between 9,000 and 10,000 calories per day.

Still not convinced? Here is what Michael Phelps eats, according to the Daily Mail:

Breakfast: three fried-egg sandwiches, three chocolate chip pancakes, a five-egg omelette, three sugar-coated slices of French toast, and a bowl of grits

Dinner: another pound of pasta, followed by pizza and more energy drinks.

Likely, Phelps grazes on his meals, somewhat, rather than eat them in sittings. But even so, that is a lot of food!

Add to this thermogenic effect the fact that pool activities are great for the ever-increasing percentage of the population that is significantly obese, especially the all-too-common morbidly obese folks who may not exercise in a gym out of fear of injury or embarrassment, and getting in the water gets to be a very attractive prospect.

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