Kristian rose to prominence in 2008 when he was crowned senior British champion. He followed this up with a superb performance at the 2009 World Championships in London where he came 6th in the all-around. In 2012 he was part of the British team that famously won Olympic bronze in London before he came back from a minor injury in 2013 to take bronze on vault at the World Championships. In 2015 Kristian won the European Championship floor gold before claiming silver as part of Team GB at the World Championships in Glasgow and then most recently, at the 2016 European Championships, he was part of the team that won silver, before taking individual high-bar silver. Named the captain for Team GB's gymnastics squad for the Olympic Games in Rio, Kristian helped the team finish in 4th, and also made the individual floor final, finishing 7th.