The Duke of Cambridge joked that he was like "giraffe on ice" on a football field during a visit to an academy school in south-east London.
He said: "Watching me on the football field is never a pretty sight – the expression giraffe on ice springs to mind.
"However it is marginally less embarrassing than seeing my brother cheat his way to becoming the fastest man on the planet!
"Catherine, on the other hand, with a tennis racquet or a hockey stick is something to behold and be aware of."
The royals visited the academy school to attend the launch of a new project that is being supported by their charitable Foundation.
The Duke and Duchess of Cambridge and Prince Harry arrive for the launch of a new sports project in south east London that aims to train the next generation of sports coaches.
Young trainers are expected to put their students through their paces for the royal trio, whose charitable foundation is supporting the initiative.
Judo, basketball, five-a-side football and table tennis will be demonstrated for William, Kate and Harry during a visit to a college in Rotherhithe.
This ITV News report by James Mates rounds up some of the highlights of the Duke and Duchess of Cambridge's wedding day on the 29th April 2011.
April 29 2011 - Prince William and Catherine Middleton marry at Westminster Abbey.
May - The royal couple honeymoon in the Seychelles.
June - William and Kate attend their first public engagement as a married couple at a gala for the Absolute Return for Kids (Ark) charity.
July - The pair embark on a 10-day tour of Canada and California.
August - The Duke and Duchess visit Birmingham to show their support for those affected by the summer riots.
September - The couple open a cancer treatment centre together at the Royal Marsden hospital in Surrey.
October - Commonwealth leaders agree on an historic change to give sex equality in royal succession.
November - The couple announce they will establish their own London base at Princess Margaret's former home at Kensington Palace.
December - William and Kate visit homeless youngsters just before Christmas in London, and acquire a cocker spaniel puppy called Lupo.
January 2012 - The royal couple see in the New Year in a reindeer herder's tepee pitched at the Duchess' parents' home in Bucklebury, Berkshire.
February - William continues his RAF service as a search and rescue pilot in the Falkland Islands.
March - The Duchess of Cambridge speaks in public for the first time as the patron of a children's hospice near Ipswich.
April - The couple celebrate their first year of marriage.
The Duke and Duchess of Cambridge will spend this weekend with friends as they mark their first wedding anniversary.
William and Kate will travel to an undisclosed location in the UK to join friends for a celebration - but not their own.
The Duke and Duchess of Cambridge celebrate their first year of marriage with friends.Read the full story ›