EUGENE, Oregon, June 17 (Reuters) - Shelby Houlihan will be allowed to compete in the 1,500 metres and 5,000m at the U.S. Olympic trials despite receiving a four-year ban for testing positive for an anabolic steroid pending an appeal, USA Track & Field (USATF) said on Thursday. The 28-year-old American record-holder said this week the Athletics Integrity Unit informed her in January that a test showed she had returned an "adverse analytical finding" for nandrolone. Houlihan denied knowingly ingesting the substance and said she was innocent of any wrongdoing. read more "Given there is an active appeal process, USATF will allow any athletes to continue competing until the process is completed," USATF Managing Director of Communications Susan Hazzard said in a written statement. A start list for Friday"s events, when the trials are set to get undwrway in Eugene, Oregon, show Houlihan is registered to compete in the 1,500m and 5,000m events.