in
Kassel. On 18 July 2007, his blood tested positive for
testosterone and he was suspended by his team. On 31 July 2007, Sinkewitz was fired by T-Mobile after he declined to have his "B" or second blood sample tested. He admitted using Testogel, a testosterone ointment. Sinkewitz was banned for one year, until 17 July 2008. In 2009, Sinkewitz joined the Czech-based team PSK Whirlpool. He went on to ride for Team ISD for the 2010 and 2011 seasons. On 18 March 2011 the
Union Cycliste Internationale (UCI) announced that Sinkewitz had tested positive for recombinant Human Growth Hormone in a blood sample taken during the GP di Lugano earlier in the year. He was provisionally suspended by the UCI, and a B-sample was analysed a month later, also testing positive for HGH. Sinkewitz appealed to the German Institution of Arbitration which ruled that the calculation of the sample analysis was "not sufficiently documented and therefore the ADRV [Anti-Doping Rule Violation] not validly proven," thus clearing Sinkewitz of the ADRV and allowing him to apply for a new license. The German anti-doping agency appealed to the
Court of Arbitration for Sport (CAS), who in February 2014 found Sinkewitz "guilty of an Anti-Doping Rule Violation in the form of the presence of recombinant hGH in his body specimen", banning him for 8 years, imposing a €38,500 fine, and disqualifying all his results from the 2011 GP di Lugano. Later confirmed in the evidence of the USADA report in 2012, as well as by
University of Freiburg doctors, to have done blood transfusions during the
2006 Tour de France alongside some of his teammates on the
T-Mobile Team. ==Major results==