Defying the laws of physics not to mention sanity, Xie Guanghai, a university professor from Luoyang, central China’s Henan Province, claims he does about 4,000 push-ups on upturned knives every day.

It took the 57-year-old educator four years of daily practice to master the technique of doing press-ups on knives fixed into place on a wooden board. His palms have developed deep calluses, which is why his hands are never cut in the process.

His fascination for this bizarre and perilous exercise regimen took hold some four years ago after he saw a television program featuring an athlete climbing a ladder made of blades.

He began to practice and soon became obsessed with this hazardous mode of training.

The professor has already earned two world records for conventional press-ups, including one for doing 6,012 in a row. Future plans include applying for a place in the record books for blade push-ups.

“Hopefully I can achieve the record of doing the most push-ups on blades,” says Xie.

To each his own as they say, but one can only wonder about his next step along the path of personal thrills.

Will it be walking on nails or hot coals, or pirouetting around deadly snakes?

The possibilities are endless for one brilliant man whose sharpness is obviously reserved for the university classroom.