CrossFit announced on Wednesday that four athletes received doping bans in 2015 as a result of its drug testing policy.

Two athletes received two-year bans after testing positive at their regional competitions of the CrossFit Games. Tests revealed anabolic agents in the subjects’ urine. Both athletes’ bios say they hold CrossFit Level 1 certificates.

A third athlete received a ban when avoiding out-of-competition drug testing, and the fourth was shown to have anabolic traces in an out-of-competition test.

CrossFit says all athletes advancing to the CrossFit Games, its annual world championships, are tested at least once. Tests are conducted by Drug Free Sport, an agency whose clients include the NCAA, Major League Baseball’s minor league program, and the PGA Tour.