On Tuesday, at the 2017 Nathan’s Famous Hot Dog Eating Contest, Joey “Jaws” Chestnut shoved a record-breaking 72 hot dogs past his eponymous chompers. This July 4th tradition, held at Coney Island in Brooklyn, is a feat of endurance that the uninitiated should not attempt. Competitive eating stretches the limits of human anatomy and is only possible because the people who do it train their bodies to handle the unique stresses of the sport.

Chestnut, whose most recent performance broke the record of 70 hot dogs that he set in 2016, has a well-documented training regimen that’s designed to overcome his body’s physical limits. In short, he trains like a marathon runner, completing several medium-sized eating binges in the months leading up to the big show.

“It’s similar to marathon runners when they’re slowly ramping up,” he told GQ in 2015. “They hit it and hit it again.”

joey chestnut hot dogs
Joey "Jaws" Chestnut trains his stomach to stretch beyond the normal limits of human biology.

Chestnut’s training includes breathing exercises and chewing/swallowing practice, but the most significant factor limiting a competitive eater’s ability is, arguably, the elasticity of the human stomach. The average person’s stomach can hold, at most, only about one liter of food, and when it does it stretches about five times from its fasting size.

But that capacity can be expanded with time and brute force. Chestnut’s training, which reportedly includes two months of “simulated contests” in which he eats as if it were the big day, is really just training to stave off the nausea that a typical person will experience when their stomach gets full. When he trains, he also chugs a gallon of water (or sometimes milk) to help train his stomach and mind to handle the massive influx of food. After each training session, he fasts for two days to allow his stomach to return to its fasting size. A 2001 study of bulimic and obese individuals showed that people who binge eat do indeed have greater stomach elasticity than their peers, which lends credence to this training method.

As Chestnut shoves hot dogs down his gullet, dipping buns in water to help them slide down more easily and hopping up and down to aid peristalsis, his stomach stretches far beyond the usual limits. At Tuesday’s contest, he consumed more than 15 pounds of food, and that doesn’t even include the water. For the average person, that would trigger nausea and probably vomiting (known as a “reversal of fortune,” which would disqualify a competitive eater), but the increased elasticity brought about by his training helps him overcome this natural tendency.

Major League Eating, the sanctioning body for the sport, warns against training at home, as it can be dangerous. We at Inverse echo that concern: Please don’t try to beat Joey Chestnut’s hot dog eating record at home.

Photos via YouTube/ Featured Patriots, Getty Images / Alex Wroblewski