Tremors were felt in the Greek capital of Athens and as far away as the southern island of Crete
The 31-year-old, who has 19 Grand Tours stage wins including 14 on the Tour de France, terminated his contract with Team Katusha by mutual agreement in May to take a break from cycling.
He joined the Swiss outfit last year but never managed to reproduce the form that made him one of the world's best sprinters, leading him to take some time out of cycling.
"The biggest question of the last few months was: Can I and do I want to continue to make the sacrifices needed to be a world-class athlete?," Kittel said in a statement.
"And my answer is: No, I do not want that any more, because I have always found the limitations on a top athlete as an increasing loss of quality of life.
"That is why I am very happy and proud that at this point in my life I can make the decision to follow my heart in a new direction."
Kittel's last significant victory came last year in the sixth stage of the Tirreno-Adriatico week-long race while his last win on the Tour de France was in 2017.
Tremors were felt in the Greek capital of Athens and as far away as the southern island of Crete
The Buyback Programme is a huge step in creating solutions for nature
Dozens of other products that contain benikoji — including miso paste, crackers and a vinegar dressing — have been withdrawn from the market
The passengers were on a trip to an Easter weekend church gathering
Pavel Durov said measures were taken immediately to stop 'a flurry of unknown users posting messages appearing to call for violence'
Motorists have been advised to drive carefully and abide by traffic rules and regulations
Right education methodologies at the grass root level, exposes students to technologies that will impact them in their growing years
Innovation, digital transformation will pave the way for more large-scale crypto deals in future