The devotion to the rankings has its down side. While most people regard exercise as a form of healthy fun, some have become so competitive that they exercise too much, even to the point of damaging their health.

A woman surnamed Yang in Nanjing, Jiangsu province, faced having both feet amputated after days of vigorous walking in inflexible shoes left her with severe blisters that began to fester, the Yangtze Evening News reported.

Her quest to top the rankings ended up at a Nanjing hospital. Sun Xinjuan, the physician who treated her, said she should not have undertaken such prolonged and strenuous exercise. Her type-2 diabetes, which inhibits nerve receptors, prevented Yang from registering pain in her feet.

Another downside to some walkers' fierce competitive streaks? Cheating. Some devotees act dishonestly on their way to the top of the ranking table.

In August, the media was full of reports about a Nanjing woman who constantly topped the rankings table despite having a sedentary job with an e-commerce company. It was later discovered that she had strapped a fitness-tracking "wearable" bracelet to her dog's leg and let the sporty pooch do all the walking instead.

Li Ran, an associate researcher at the Sports Science Research Institute under the General Administration of Sport, which pushes for greater public participation in sports and fitness programs, praised the newfound walking craze, but warned about its drawbacks.

"It's good to see people share their walking records on social media, because it encourages others to exercise," Li said. "However, exercising is a lot like drinking alcohol, the effect varies from person to person in terms of how much is appropriate."

Walking and jogging should be undertaken with consideration of the exerciser's level of fitness and with well-fitting clothing and appropriate footwear that offer good levels of protection, he added.

But the vanity fair brought on by the competitive ranking on social media should be kept in check, he said, adding, "Keeping it individual is the key to fitness."