In April 2007, Hitchon set a new UK Under 17 Women's record with a throw of 49.61m at the
Kingston-upon-Hull AC Open meeting. The previous record was 48.94m achieved by Frances Miller of
Elgin Harriers at the
2001 IAAF World Youth Championships in
Debrecen, Hungary. In March 2008, at the age of 16, Hitchon set a new junior record with a throw of 59.74m at the UK Throws event in Birmingham, followed by a 59.49m throw at the Blackpool Open Meeting the same weekend. In July 2009, Hitchon won bronze in the hammer at the European Junior Championships. In doing so she also improved her own national junior record to 63.18m and took Britain's first ever European Junior medal in the women's hammer. A year later, Hitchon was captain of the UK women's team at the IAAF World Junior Championships (Moncton, Canada, 19–25 July), as well as remaining the UK junior hammer record holder. In July 2011, Hitchon represented the UK in the European Under-23 Championships in Ostrava, Czech Republic (14–17 July), taking the bronze medal. At the 2014 Commonwealth Games in Glasgow, Hitchon achieved a bronze medal in the women's Hammer throw with a distance of 68.72m. This was her first success at a senior level championship. At the
2016 Rio Olympics, Hitchon achieved a bronze medal in the
women's hammer throw with a distance of 74.54 metres on her final attempt, setting a new GB record in the process. It also made her the first British hammer thrower to win an Olympic medal and ended a 28-year Olympic medal drought for GB in women's field events since
Fatima Whitbread's silver at
Seoul in 1988. Hitchon announced her retirement in May 2021. ==International competitions==