Speaking on his podcast, The Good, The Bad, And The Rugby, Kate opened up about her love of sport and her competitive side.

She appeared on the show in Windsor Castle alongside the Prince of Wales and the Princess Royal.

Tindall married into the Royal Family 12 years ago when he wed Olympic equestrian Zara - the daughter of the Princess Royal.

Asking Kate where her competitive side came from, Tindall revealed he had seen the royal play beer pong.

He said: "I'm not going to say you're uber competitive... [but] I've seen her play beer pong."

In response, Kate jokingly denied she is competitive at all.

She said: "I suppose as a family we were just very active.

"And I can always remember being physical, using our bodies, whether it's walking, climbing the lake district in Scotland [or] swimming from a young age.

"[My parents] always encouraged us to be physically active and sporty and they always encouraged us into doing team sports and trying things."

Beer pong is a drinking game where players throw a ping pong ball across a table in a bid to land it in one of a triangle of cups of beer at the other end.

If successful, the beer has to be consumed by the other team, and the cup removed. To win the game, you have to eliminate all the other team's cups of beer.

Kate revealed that she is a fan of cold water swimming.

"Cold swimming - the colder, the better. I absolutely love it. Slightly to the point where William's [saying] 'You're crazy' and it's dark and it's raining.

"I will go and seek out cold water. I love it."

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She also admitted that despite being married for 12 years, she and William were still very competitive with each other.

She said: "I don't think we've managed to finish a game of tennis, the two of us. It becomes a mental challenge between the two of us."

William agreed that they try to "out mental" each other.

William and Kate have spent the weekend in France to watch the start of the Rugby World Cup, with England and Wales both playing their first group-stage matches.