US athlete Shelby Houlihan believes pork burrito to blame for failed drugs test

Shelby Houlihan has been banned for four years following a positive test for what she claimed was a tainted pork burrito (Charlie Neibergall/AP)

American middle-distance runner Shelby Houlihan has blamed a burrito after being banned for four years following a positive drugs test.

The United States’ record holder in the women’s 1500m and 5,000m was told in January that the anabolic steroid nandrolone had been found in a doping sample.