She became a founder member of the ladies' section of Mitcham Athletic Club in 1926 at the age of 19. At the British Games in London in August, she broke the long jump world record with a distance of 5.485 m. Later in August, she competed at the 1926 Women's World Games in Gothenburg at which she placed second, recording 5.44 m, behind Japan's Kinue Hitomi. Cornell exceeded Hitomi's world record jump of 5.5 m, but she left a mark in the sand after she turned to speak to an official before leaving the pit.