( CNN ) -- Asafa Powell , the last man to hold the 100m world record prior to his compatriot Usain Bolt , admitted to a Jamaican disciplinary hearing on Tuesday that he had a hazy knowledge of the World Anti-Doping Agency 's list of banned products . The 31-year-old was testifying to the Jamaican Anti-Doping Commission ( JADCO ) after testing positive for the prohibited stimulant oxilofrone during last June 's national championships . The oxilofrone is said to have come from a supplement called Epiphany D1 , which Powell said he had been taking on the recommendation of his physical therapist Christopher Xuereb . `` I do n't know the list but I knew of the list , '' Powell said at the hearing in the Jamaican capital Kingston . `` I know there is a list we are supposed to check . '' When asked whether he was acquainted with the rules of doping control , the once fastest man on the planet wistfully replied : `` I am now . '' Powell , whose 100m world record mark of 9.74 seconds was beaten by Bolt in 2008 , also said that he failed to list all the supplements he was taking during the Jamaican trials because he could not recall the relevant names . `` All the supplements were new to me , so I could not remember all of them , '' he explained , adding that he started taking them roughly a month before the Jamaican championships began on June 20 . Among the absentees from the list was Epiphany D1 . `` I could not remember after all the excitement at the trials , '' the Jamaican said . Powell also told the hearing that he doubled the dosage of his supplements on the morning of his positive drugs test , saying he had been told by Xuereb to take two capsules of Epiphany D1 each morning for seven days before doubling the dosage the following week . `` I did n't remember to do that , '' said Powell , whose hearing is expected to last at least two days . `` Chris ( Xuereb ) came to my room the morning of the trials and said I must remember to take four . '' Powell says he was advised to take the supplements after Xuereb , who the sprinter described as a good friend , told him he should be using them ahead of his early morning training . Prior to that , the Jamaican had regularly trained without consuming anything - not even breakfast , he explained . Powell 's hearing before a three-member panel comes after his training partner Sherone Simpson , a three-time Olympic medalist , was also forced to explain her positive test for the same stimulant . Like Powell , she denies knowingly taking the banned stimulant and her case earlier this month was adjourned until February 4 . The athletes have been provisionally suspended since their failed tests , with both missing out on last year 's World Championships in Moscow . A total of five Jamaican athletes failed drugs tests at the national championships in June , prompting the entire JADCO board to resign five months later -- with criticism over a lack of testing by the body 's former executive director Renee Anne Shirley ringing in their ears . The hearing will resume on Wednesday , with agent Paul Doyle - who represents both Powell and Simpson - set to testify .
Former 100m world record holder testifies about failed test to Jamaican doping commission . Asafa Powell says he could not remember the names of all the supplements he was taking . Sprinter was one of five Jamaicans to test positive for a banned substance in 2013 .