The Duchess of Cambridge takes to the racetrack and tries her hand at sparring during a visit to the London Stadium in Stratford. Kate was attending an event hosted by SportsAid where she was also joined by former world boxing champion David Hayes and Olympic gold-medallist Jessica Ennis-Hill. Report by Chinnianl. Like us on Facebook at http://www.facebook.com/itn and follow us on Twitter at http://twitter.com/itn