Ciolek, 30, came to prominence when he won the German national road title in 2004 as a 19-year-old. The highlight of his career was winning the snow-shortened Milano-SanRemo in 2013 with Team MTN-Qhubeka. He had only four other victories after that, and moved to Stölting in 2016.
"Gerald will not be underway in the professional peloton this year. For now a return to professional cycling is not planned," his manager Ken Sommer told Tour magazine.
Ciolek rode for Akud Arnolds Sicherheit and Wiesenhof Akud before joining the ProTour with T-Mobile, Milram and QuickStep. He returned to the Professional Continental level in 2013 with MTN.
Gerdemann, 34, announced his retirement the end of December in the Mallorca Magazine. Together with his girlfriend he now runs a restaurant on the island.
Once considered the “next German Wunderkind”, Gerdemann never lived up to the title. In 2007, he won a mountain stage in the Tour de France whilst riding for T-Mobile, moving into the yellow jersey which he wore for one stage. He also won the Deutschland Tour (2008), the Bayern Rundfahrt (2009) and the Tour of Luxembourg (2011 and 2015).
Gerdemann turned pro with CSC in 2005, with the team releasing him from his contract to join T-Mobile in 2006. Together with Ciolek he moved to Milram in 2009, and then went to Leopard Trek for 2011 and 2012. Unable to find a team, he sat out the 2013 season before joining MTN-Qhubeka for 2014. In 2015 he rode for Cult Energy Pro Cycling, which became Stölting in 2016.