Sha’Carri Richardson was considered a favorite to win the 100-meter race at the Tokyo Olympics next month until a positive marijuana test derailed her chances. The US track and field athlete was suspended and taken off the US Olympic roster this week. The news sparked a debate on whether athletes should be allowed to consume marijuana. But to understand the drug’s impact on athletes, The World’s Marco Werman spoke with Dr. Michael Joyner, a researcher and physician at the Mayo Clinic in Minnesota.