A Chinese man has been getting a lot of attention on Asian social media, because of his unique training regimen – walking with 150 kg of steel plates attached to his feet.

Zhang Enshun, a 42-year-old man from Yulin City, in China’s Guangxi province, has been training in the art of “iron shoes” for the last five months, and has already made significant progress. After seeing news reports of people working out by walking with heavy weights attached to their feet, and hearing them talk about the benefits of this training, Zhang decided to try it for himself. He began by attaching one steel plate, weighing around 18.75 kilograms, to each of his feet and trying to take a few steps with it. Today, he can walk around with four of these heavy plates attached to each foot, for a total weight of 150 kilograms.

“The weight of these shoes is more than twice my body weight, but I can walk more than 50 meters in them in around 20 minutes,” Zhang Enshun said, adding that he walks between 200 and 300 meters in his iron shoes every day.

Before starting his iron shoe training, Zhang fastens the iron blocks to his feet using thick belts. When he walks he also does tai chi, for a more complete workout. He recently told local reporters that he has made great progress in the last five months. Despite quadrupling the weight on each foot, he is still able to lift his feet 2 centimeters off the ground, and advance up to 20 centimeters with each step.

The 42-year-old claims that apart from strengthening his muscles and leg bones, the iron shoe workout improves his blood circulation and keeps his joints healthy. However, experts warn that this sort of exercise, which has been practiced in China for some time, has its risks.

Deputy Chief Physician Liang Zhou of the Yulin Integrated Traditional Chinese and Western Orthopedic Hospital told HK01 News that everyone’s bones are different, and that the pressure a person’s bones and joints can withstand is limited, so increasing the weight of the iron shoes too much can cause serious injuries. Dr. Liang advised anyone wanting to take up this workout to exercise great caution.

Zhang Enshun is just one of several Chinese people to gain internet fame for training in the art of iron shoes. Back in 2012, a man named Wu Kong set a national record for walking in a pair of custom iron shoes weighing an estimated 400 kilograms, and just last year, a self-proclaimed Iron Shoe King made headlines for walking with 140 kilograms of weight attached to his feet.