Kate, who is known for her competitive streak, joined a team of pupils being supported by Dame Kelly’s trust at its base in Bath, with the former sports star on the other team.
The children from St Katherine’s School in Bristol are taking part in the On Track To Achieve programme, delivered by their athlete mentor and Paralympic gold medallist Liz Johnson.
In bright summer sunshine on Tuesday, the opposing groups had to run forwards in turn and throw a bean-bag on to a grid on the ground.
Kate did her best but Dame Kelly’s team won twice.
After the first victory, the track and field star held her arms aloft and admitted she is ‘slightly competitive’.
The Princess joked: ‘You would never have guessed.’
Dame Kelly founded her national youth development organisation on the belief every young person needs a champion.
It pairs world class athletes with youngsters, who may lack confidence or have other issues, so the sportsmen or women can pass on their winning mindset and help the schoolchildren develop the skills and confidence they need to succeed in life.
The princess later sat down to chat to the pupils, all girls aged from 11-13, who spoke about their experiences at school, home life and the benefits of being mentored by a sports star.
Today’s engagement comes amidst Mental Health Awareness week, and the royal went on to discuss with them how working with an athlete mentor has supported them.
They explained how the charity had helped them to better express their emotions, build resilience, and promote positive mental health and wellbeing.
The scheme is targeted towards 11-19 year olds, primarily those with social, emotional or mental health challenges, or children who would benefit from the support of a positive role model to achieve their potential.
It also helps young people to build healthy relationships in school and with the wider community and understand the importance of physical and mental wellness.
The Princess has long been a champion of prioritising mental wellbeing, including that of children and young people.
She has dedicated her time to supporting various mental health programmes, and is a patron of a number of charities which are focussed on promoting and providing mental health support to those in need.
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