Turner played 7-a-side soccer as a midfielder for New South Wales starting in 2009, and for the Australian national 7-a-side team, the ParaRoos, in 2012. By November 2013, he had 16 caps, and was named Pararoo Football Player of the Year at the 2013 FFA Australian Football Awards night on 13 November 2013. The head coach of the ParaRoos, Paul Brown, said that "James has pace to burn and he gets forward on the overlap to worry defenders in their third. He has the potential to be one of the best players that Australia has ever produced if he stays on the path that he is at present". Unfortunately for the ParaRoos, ranked tenth in the world, in July 2014, the Australian Sports Commission cut funding for the 7-a-side soccer program on the grounds that the team was unlikely to make the 2016 Summer Paralympics. After a public outcry, the team was revived with a new funding model in 2015. Despite the fund raising efforts, the ParaRoos failed to qualify for Rio.
Athletics
Turner started with Forster-Tuncurry Athletics club as an eight-year-old and at the age of 15 joined the Hunter Academy of Sport AWD middle distance running program. In 2015, Turner turned his talents to back athletics on the encouragement of Athletics Australia, where he is classified as a T36 athlete. He was coached first by Marie Kay and from 2016 by Brett Robinson in Wollongong, New South Wales. At the Australian Athletics Championships in March 2016, he ran the 800m in 2:08.90, which was a Paralympic qualifier. In the IPC Grand Prix in Canberra February, he had posted an even faster time of 2.08.8. In August 2016, it was announced that had been selected to represent Australia at the 2016 Summer Paralympics in Rio de Janeiro in the 800m event. He was ranked number two in the world in this event in his classification. At the 2016 Summer Paralympics, he won the Men's 800 m T36 in a world record time of 2:02.39. In December 2016, he was named Australian Paralympic Rookie of the Year. At the 2017 World Para Athletics Championships in London, England, Turner won three gold medals - Men's 200 m T36,Men's 400 m T36 and Men's 800 m T46. His Rio Paralympics gold medal event the 800m is not on the 2020 Tokyo Paralympics as a result he has changed to short distances - 100m, 200 m and 400 m. At the 2019 World Para Athletics Championships in Dubai, he ran 11.72 and broke the world record in winning the Men's 100 m T36 and followed up with gold in the Men's 400 m T46 in a world record time of 51.71. In 2019, he is coached by Iryna Dvoskina in Canberra.
Recognition
2016 - Awarded Athletics Australia 2016 Male Para-athlete of the Year.