Did Michael Phelps demand 12,000 calories a day due to "thermal dieting?"

Your body generates a temperature on average of 98.6 degrees, duh!, but what if you challenge it with cooler temperatures? Would cooler temps force your body to burn more calories to heat itself?

A NASA scientist thinks so and believes that Michael Phelps was forced to consume roughly 12,000 a day just to maintain his weight due to the thermal challenges he faced while swimming hours-upon-hours a day..

From RedOrbit:

"The body wants to maintain a balance, a homeostasis of 98.6 degrees," author Tim Ferriss, the man who penned the best-selling book 'The 4-Hour Body,' told ABC's Sarah Netter during a December 15 interview. "If you make it cold, the body will do everything it can to get back to 98.6. And it has to burn calories to do that--heat equals calories."

The technique is known as 'thermal dieting' and according to Ferriss, people can burn up to 50 more calories simply by forcing their bodies to endure sub-freezing temperatures. Doing so forces a person's system to work harder and burn a type of fat known as brown adipose tissue (BAT) to produce heat.

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