Remember this youthful 49-year-old mum? Older photos of her revealed

The 49-year-old mother who recently made waves online because of her youthful appearance has shared more photos of herself, including those from the past when she was younger.

Liu Yelin looks like a model in her 20s, but is actually hitting 50 this year.

The fitness enthusiast goes through a gruelling two-hour workout routine daily and is also an avid swimmer even in winter.

According to Bored Panda, Liu has swam across the Yangtse River in China and the Han River in South Korea.

An even more incredible feat was when she swam almost 12km in just four hours, from Penang to the Strait of Malacca.

She is also often mistaken for her 22-year-old son's girlfriend when the two take pictures together.

With over 86,000 fans on Weibo, Liu has become the talk of the town and the Internet's latest celebrity.

Besides regular selfies, she also posted photos comparing her 15-year-old, 30-year-old and present selves.

She said, "If you think you look rough, that’s because you haven’t sweated enough."

Check out a new set of photos of Liu in the gallery above.