Jamaica’s Usain Bolt has chosen not to race again this year after securing all three sprint titles at last month’s world championships in Beijing. It was the fifth time at a major global event that the 29-year-old Jamaican has won all three events and he said: “I am already thinking about next year and the 2016 Olympic Games in Rio where I will attempt to defend my titles in the 100m, 200m and 4x100m. “I will enjoy a short break from training now to recharge before resuming background training next month.”