Costa is the most tested fighter in the history of UFC and USADA cooperation

Brazilian UFC middleweight Paulo Costa became the absolute leader in the number of doping tests he passed to USADA. During the 8-year partnership between the promotion and the organization, Costa was tested 135 times. ...

Also rounding out the top five most tested athletes were Kamaru Usman (97), TJ Dillashaw (92) and Amanda Nunes (90).