From the 2010 season onwards he transitioned towards longer road races. In his first road race outside Kenya, and his half marathon debut, he took the title at the Roma-Ostia Half Marathon.[4] Two months after he won the Nice Half Marathon with a run of 1:01:34 hours.[5] In September he equalled that time for a fourth-place finish at the Philadelphia Distance Run (a race won by his older brother).[6] A debut over the full marathon distance followed a month later at the Venice Marathon and he finished eighth but was some distance behind the winner with his time of 2:15:17 hours.[7] He had two outings over that distance in 2011: he came third at the Maratona di Sant'Antonio in Padua with a best of 2:10:16 hours and placed fourth at the Košice Peace Marathon.[8]
Some's first marathon victory came in 2012 at the Brighton Marathon, where he beat the previous course record by over four minutes with his run of 2:12:03 hours.[9] Controversy struck his family that year as his brother Matthew Kisorio tested positive for steroids at the national championships and Kisorio admitted to doping, saying that doctors systemically doped athletes in the country.[10] Some were unaffected by the situation and in October he improved his marathon best by three and a half minutes at the high-profile Frankfurt Marathon, coming in fourth place.[11]
