Britney Spears was “obviously joking” when she claimed she completed a 100 metre sprint faster than world record holder Usain Bolt.The Toxic hitmaker, who broke her foot in February, took to Instagram on Wednesday to post a screenshot of her stopwatch timer paused at 5.97 seconds as she shared words of fitness encouragement.However, she left her followers confused after using the caption to suggest she had recorded the time for a “100 meter dash,” even though Olympic gold medallist Bolt currently holds the world record for the distance, which he completed in 9.58 seconds back in 2009.Returning to the site, the 38-year-old updated fans, admitted the post was made in jest – but teased she’s “coming for the world record.”“obviously I was