WATCH: Senior citizens strut their bodies in Grandbikini contest in China

TIANJIN, China - Organisers call it the 'Grandbikini' event - an exclusive bikini contest open only to those aged 55 and above.

It kicked off Saturday with more than 400 people showing off their figures at a local water park in Tianjin, including a handful of men eager to pose.

The contest is in its third year running, organised by a senior citizens' committee to promote health and wellness.

A panel of judges rate participants on criteria like stage presence, smiles and gestures, many of them already regulars to the contest.

That includes the oldest participent, Ma Jing, a 78-year-old cancer survivor taking part in her blue bikini.

"I'm very honoured. If I can take part in a bikini contest at this age, for me it means I'm mentally happy and physically healthy," she said.

By the time the event wound down, the jury handed out more than 100 awards. But for many, it was more about confidence, encouraging a positive attitude towards growing older, and perhaps trying to prove that age is just a number.

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