Dame Laura Kenny, Britain's most successful female Olympic athlete, has announced her cycling retirement.The 31-year-old, who has won five Olympic gold medals in her decorated career, had been expected to compete at the Paris Games this summer, but told the BBC it was time to stop.

Dame Laura Kenny, Britain's most successful female Olympic athlete, has announced her cycling retirement.The 31-year-old, who has won five Olympic gold medals in her decorated career, had been expected to compete at the Paris Games this summer, but told the BBC it was time to stop.