Are Chinese children becoming the sick men of East Asia? A recent story by Japanese news outlet Diamond Online comparing the physical fitness of Chinese and Japanese youngsters triggered a raging debate between netizens in both countries.

It all started with a heavy snowfall in Tokyo last month. The sight of fit, miniskirt-clad Japanese girls strolling in the streets in such chilly weather piqued interest among Chinese tourists clad in windbreakers and greatcoats, and their compatriot bloggers back home as well.

Some Chinese people opined that Japanese teenagers were physically stronger than their Chinese counterparts, many of whom nowadays are couch potatoes partaking of pizzas and fries and barely walking or moving throughout the day.

The Diamond article said millennials in China were spoiled, feeble and fragile. ”In winter, pediatric departments in major hospitals in China are jammed with teenage patients,” the website claimed.

Soon Japanese netizens started jeering at the disparity in physical strength and dexterity between youngsters of the two countries.

But before long Chinese state media joined the debate and refuted the comparisons, citing the difference in climate between the two countries. The temperatures of Japan’s marine climate, especially in winter, and those of China’s continental monsoon climate can be poles apart. Winters are generally more frigid in China.

“Japanese kids should try to wear miniskirts in northeastern China and then decide who is stronger,” said one commenter.

“If Japanese people think wearing thin clothes in winter is something laudable, then they should know that winter swimming is a craze in China,” said another.

Chinese parents also came to the defense of their kids.

“This winter, I usually see quite a few toddlers running and playing in my neighborhood and parks. On a frigid day last week, I saw a group of boys playing football in thin jerseys, jumping to give their coach a high five,” one mother told the Global Times, adding that she also hits the gym with her son several times a week.

“I will be concerned with whether he will be good at math or make a lot of friends, but that he has a strong physique is my biggest wish. Compared [with] tutorial class, I would be happier if he is more interested in ball games, taekwondo or skiing,” she said.