Paul and Craig Pumphrey have built there careers breaking stuff. The two brothers are Breaking Technique Experts who hold five world records for outrageous feats of strength.

Fight Science used an accelerometer from their car crash labs to measure the amount of striking force each of these men have, and what you’ll see is amazing. Each of them are able to generate over 2000 pounds of striking force, which is equivalent to a 35mph car slamming into a brick wall!

This type of hard body training isn’t new. The Chinese were doing it thousands of years ago, back at the Shaolin Temple. What is new, is the ability to finally measure the exact amount of force that’s generated by a trained martial artist.

Wolff’s Law explains why ordinary human bones don’t shatter under such extreme force - “If loading on a particular bone increases, the bone will remodel itself over time to become stronger to resist that sort of loading.”

This is just one part of the complete Fight Science series, that airs on National Geographic.