Blue Peter: Little Mix, Kian Egan, Lizzy Yarnold and the 31-Legged Race

It's the final challenge for Team Blue Peter in this Sport Relief special. Lindsey, Barney and Radzi mentor three different schools in a running event with a twist - an incredible 31-legged race. Plus, Winter Olympic Gold medallist Lizzy Yarnold is in the studio to help make some super-healthy, sporty treats, and there's a performance from former Westlife star and current King of the Jungle, Kian Egan live on the show.